International Journal of Molecular Zoology 2024, Vol.14 http://www.animalscipublisher.com/index.php/ijmz © 2024 AnimalSci Publisher, registered at the publishing platform that is operated by Sophia Publishing Group, founded in British Columbia of Canada. All Rights Reserved.
International Journal of Molecular Zoology 2024, Vol.14 http://www.animalscipublisher.com/index.php/ijmz © 2024 AnimalSci Publisher, registered at the publishing platform that is operated by Sophia Publishing Group, founded in British Columbia of Canada. All Rights Reserved. Publisher AnimalSci Publisher Edited by Editorial Team of International Journal of Molecular Zoology Email: edit@ijmz.animalscipublisher.com Website: http://www.animalscipublisher.com/index.php/ijmz Address: 11388 Stevenston Hwy, PO Box 96016, Richmond, V7A 5J5, British Columbia Canada International Journal of Molecular Zoology (ISSN 1927-534X) is an open access, peer reviewed journal published online by AnimalSci Publisher. The journal is publishing all the latest and outstanding research articles, letters and reviews in all aspects of molecular zoology, containing behavior, structure, evolution, classification, habits and distribution of animals, also including the relative fields on embryology, developmental biology, systematics, genetics and genomics, ecology, physiology, as well as biochemistry. Meanwhile we also publish the articles related to basic research, such as anatomy, morphology and taxonomy, which are fundamental to molecular technique’s innovation and development. All the articles published in International Journal of Molecular Zoology are Open Access, and are distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. AnimalSci Publisher uses CrossCheck service to identify academic plagiarism through the world’s leading plagiarism prevention tool, iParadigms, and to protect the original authors’ copyrights. AnimalSci Publisher is an international Open Access publisher specializing in animal science, and veterinary-related research registered at the publishing platform that is operated by Sophia Publishing Group (SPG), founded in British Columbia of Canada. .
International Journal of Molecular Zoology (online), 2024, Vol. 14, No. 1 ISSN 1927-534X https://animalscipublisher.com/index.php/ijmz/index © 2024 AnimalSci Publisher, registered at the publishing platform that is operated by Sophia Publishing Group, founded in British Columbia of Canada. All Rights Reserved. Latest Content Analysis of Cat's Communication Style and Cognitive Ability Mengyi Xu International Journal of Molecular Zoology, 2024, Vol. 14, No. 1, 1-8 Applications of Mouse Gene Editing Technology in the Treatment of Hereditary Blindness Zhenni Lu International Journal of Molecular Zoology, 2024, Vol. 14, No. 1, 9-17 From Gene to Function: Exploring the Effects of ACTA2 Gene Variants on Cardiac Development Yeping Han International Journal of Molecular Zoology, 2024, Vol. 14, No. 1, 18-21 Review of Porcine Disease Resistance Genetic Basis Research Based on GWAS Xiao Zhu, Xiaofang Lin International Journal of Molecular Zoology, 2024, Vol. 14, No. 1, 22-30 The Application of Single-cell Omics in Developmental Biology: from Model Organisms to Humans Wei Wang International Journal of Molecular Zoology, 2024, Vol. 14, No. 1, 31-43 Progress in Genetic Research on Behavioral Traits in Livestock: Application of Whole Genome Association Analysis Ming Guo International Journal of Molecular Zoology, 2024, Vol. 14, No. 1, 44-53 The Relationship between Epigenetic Changes and Seasonal Changes in Rabbits Mengshi Jiang International Journal of Molecular Zoology, 2024, Vol. 14, No. 1, 54-61
International Journal of Molecular Zoology 2024, Vol.14, No.1, 1-8 http://animalscipublisher.com/index.php/ijmz 1 A Review Open Access Analysis of Cat's Communication Style and Cognitive Ability Mengyi Xu Institute of Life Science, Jiyang College of Zhejiang A&F University, Zhuji, 311800, China Corresponding author email: 2373950793@qq.com International Journal of Molecular Zoology, 2024, Vol.14, No.1 doi: 10.5376/ijmz.2024.14.0001 Received: 29 Oct., 2023 Accepted: 08 Dec., 2023 Published: 01 Jan., 2024 Copyright © 2024 Xu, This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Preferred citation for this article: Xu M.Y., 2024, Analysis of cat's communication style and cognitive ability, International Journal of Molecular Zoology, 14(1): 1-8 (doi: 10.5376/ijmz.2024.14.0001) Abstract Cats, as social animals, employ various methods to communicate and express themselves. This review aims to explore the diverse communication methods of cats, including vocalizations, postures, olfactory cues, and physical contact, as well as their cognitive abilities. Vocal communication is particularly prominent, with purring, meowing, growling, and hissing conveying different emotions and needs. Additionally, postures and movements also serve as a means of communication for cats, such as body rubbing, shoulder raising, and stretching. Olfactory communication, through licking and cheek rubbing, helps cats identify identities and states. Lastly, the review delves into the cognitive abilities of cats, including olfactory acuity, spatial awareness, problem-solving skills, and emotional recognition. These unique communication methods and cognitive abilities enrich our interaction with cats, providing deeper insights into their colorful inner world. Keywords Cat communication; Vocalizations and postures; Olfactory and physical contact; Cognitive abilities; Social interaction Cats, as typical representatives of social animals, communicate and express themselves in various complex and subtle ways. In human life, cats have become indispensable companions, and understanding their communication methods and cognitive abilities can help people better interact with them and establish deep connections. Whether they act as companions in leisure or exhibit fascinating behaviors in their own world, cats interact with humans in their unique ways (Turner and Bateson, 2014). However, delving into the communication methods and cognitive abilities of cats is a topic that few have genuinely contemplated. That's precisely why this review is fortunate to take this perspective, offering a glimpse into the mysteries of cat communication and the remarkable intelligence they display in adapting to their environment and forming emotional bonds. In the communication of cats, various forms such as sound, posture, olfaction, and physical contact interweave to create a delicate language. Cat vocalizations include purring, meowing, growling, and hissing, each conveying different emotions and information (Vitale, 2022). Additionally, cat postures and actions play significant roles, such as body rubbing, shoulder shrugs, and stretching, expressing their emotional states and intentions. Olfactory communication is a unique method for cats, as grooming and cheek rubbing serve not only for grooming but also for conveying scent information, used for marking territory or expressing closeness. Furthermore, tactile communication is also vital in cat social interactions, with intimate physical contact conveying feelings of friendliness, closeness, and comfort. At the same time, the cognitive abilities of cats are a fascinating subject of inquiry. Their acute sense of smell gives scent a prominent role in feline cognition, enabling them to identify the identity, emotions, and status of conspecifics through scent. Cats are also highly sensitive to spatial perception, accurately recognizing their territory and adapting to changes in different environments. Problem-solving ability is another standout feature of cats, as they tend to independently address problems, even using their paws, mouths, and other tools to solve them. In terms of emotional cognition, cats' sensitivity to their owners' emotions is astonishing, expressing joy, anger, sadness, and happiness through various cognitive behaviors, thus forming deep bonds with humans. By delving into the social communication methods and cognitive abilities of cats, humans can gain a better understanding of these adorable creatures. This review will provide a detailed analysis of cat vocal communication, postures and actions, olfactory communication, tactile communication, and emotional cognition,
International Journal of Molecular Zoology 2024, Vol.14, No.1, 1-8 http://animalscipublisher.com/index.php/ijmz 2 with the aim of revealing this unique form of communication between cats and humans and their profound cognitive abilities. Through this understanding, humans can harmoniously coexist with cats, creating a closer and warmer home environment. 1 Cats’ Communication Methods Cats, as precious companions in human life, bring joy and closeness to people through their unique communication methods. In this mysterious world, cats express their emotions and intentions through various means, including vocalizations, olfaction, and physical contact. This review will deeply discuss cats’ vocal communication, including purring, meowing, growling, and hissing (Yeon et al., 2011), as well as other communication methods such as postures, olfaction, and tactile interactions, revealing their emotional world and means of communication. 1.1 Vocal communication Sound serves as a vital avenue for cat communication, with different sounds representing various emotions and needs (McComb et al., 2009). Through sound, cats can convey information without the need for words. Purring is one of the most comforting sounds cats produce, often evoking warmth and closeness. This sound is typically generated when a cat feels relaxed and content. When a cat curls up in its owner's embrace and softly purrs, it's expressing its happiness and comfort. Research indicates that purring occurs within a frequency range of 25 to 150 Hz, which may promote bone healing to some extent, making it a natural response in a cat's body. Meowing is one of the most common sounds cats make, and it serves as a primary means of communication with humans. Cats meow in specific contexts, such as when they need food, want to go outside, seek companionship, or express dissatisfaction. The pitch and tone of meowing can convey the cat's emotions and needs. When cats are hungry, their meows may be sharper and more frequent, while meowing may sound more lingering and melodious when they feel lonely. Growling is typically a sound cats make when they perceive a threat or harbor aggression. This sound is accompanied by behaviors such as puffing up their bodies, lowering their heads, and raising their fur, signifying their hostility and warning. Growling plays a significant role in feline social interactions, conveying intimidation during territorial disputes or resource conflicts, preventing conflicts from escalating. Hissing is a sound often produced when cats feel uncomfortable or frightened. It is usually accompanied by open mouths, revealing sharp canines (Figure 1), and may be accompanied by paw swatting on the ground to exaggerate their intimidating appearance. When cats feel uneasy or threatened, they may use hissing as a tactic to deter potential threats. Figure 1 A hissed cat Through vocal communication, cats can precisely convey their emotions and needs, building deep connections with humans and other cats. These sounds are not just a part of a cat's daily life but also provide a window for
International Journal of Molecular Zoology 2024, Vol.14, No.1, 1-8 http://animalscipublisher.com/index.php/ijmz 3 people to understand their emotional world (Saito and Shinozuka, 2013). In the world of cats, vocal communication is a subtle and fascinating language that deserves in-depth exploration. 1.2 Postures and movements In the cat world, language isn't the sole means of communication. In addition to vocal communication, postures and movements play a crucial role in conveying emotions, intentions, and relationships among cats. Let's explore cat postures and movements in detail, including body rubbing, shoulder shrugging, and stretching. Body rubbing is a common social behavior among cats and between cats and humans, representing friendliness and closeness (Bernstein, 2007). When a cat rubs its head, body, or tail against another cat or a human, it is, in fact, sharing its scent, expressing mutual recognition and friendship. This behavior is both a form of social interaction and a bridge for establishing connections, allowing cats to better understand each other's identity. Body rubbing can occur both within the home and when cats are exploring new environments. Regardless of the context, body rubbing highlights the emotional bonds among cats and between cats and humans. Cats use postures and movements to convey emotions, with shoulder shrugging being a distinctive behavior when a cat is feeling wary, dissatisfied, or fearful. When a cat is nervous or feels insecure, it may tense its body, causing its fur to stand on end, making itself appear larger. This posture signifies the cat's unease and vigilance, as it tries to protect itself and appear more intimidating in situations involving unfamiliar or potentially threatening elements. The shrugging gesture fully illustrates the cats' self-protection awareness and the behaviors they adopt in the face of unfamiliar or unsafe situations. Cats often assume a stretched body posture when they feel comfortable and relaxed. When a cat lies down, stretches out its limbs, and sometimes even rolls over, it's expressing satisfaction and relaxation. This behavior not only helps cats stretch their bodies but also showcases their inner calm and joy. This relaxed posture typically appears in environments where cats feel safe and comfortable, reflecting their emotional state and mental well-being. Cats communicate a rich array of emotions and intentions through various postures and movements. Behaviors like body rubbing, shoulder shrugging, and stretching not only reveal their interactions with other members and humans but also provide a window into understanding a cat's emotional world. A deeper understanding of these postures and movements can help people better comprehend a cat's needs, emotions, and social relationships. 1.3 Olfactory communication In the realm of cat communication, olfaction also plays a significant role. Through behaviors such as grooming and cheek rubbing, cats can convey scent information, mark territory, and express affection. Let's explore cat olfactory communication methods in detail. Grooming is a common social behavior among cats, serving not only to maintain personal hygiene but also to convey scent information, strengthening their relationships. When a cat grooms another cat, they are not only taking care of their cleanliness but also transferring their scent (Figure 2). This scent information holds significant meaning within a cat group, helping to confirm identities, status, and mutual relationships. Moreover, when a mother cat grooms her kittens, she also transmits scent information in this way, reinforcing the bond between mother and offspring. Cheek rubbing is a prominent behavior both in interactions among cats and between cats and humans. When a cat rubs its cheek against an object, another cat, or a human, it is essentially releasing a specific secretion from its cheek glands. This secretion contains individual information, essentially acting as a "scent business card" that can be smelled by other cats, enabling them to identify its source. Cheek rubbing not only helps mark territory but also conveys closeness and friendliness. When a cat rubs its cheek against another cat or a human, it conveys a message of an intimate relationship, aiding in building connections within social interactions.
International Journal of Molecular Zoology 2024, Vol.14, No.1, 1-8 http://animalscipublisher.com/index.php/ijmz 4 Figure 2 Licking cat Cats exhibit a high degree of sensitivity and importance toward scent information through olfactory communication. Behaviors such as grooming and cheek rubbing are not only forms of social interaction but also critical pathways for cats to understand each other, confirm identities, and establish relationships. A profound understanding of these olfactory communication behaviors can help people better understand cat social behavior and their emotional world. 1.4 Tactile communication In addition to vocalizations, postures, and olfactory communication, cats also employ tactile communication to express emotions and build social relationships. Intimate physical contact is a common way through which cats convey friendliness, closeness, and comfort. Intimate physical contact among cats is a straightforward and direct social method. When cats get close to another cat or a human, curl up together, or lean against each other (Figure 3), they convey closeness and a sense of security. This behavior strengthens the connection between individuals, building a more intimate social relationship. For instance, a cat might lie down next to its owner, allowing gentle strokes on its head or back. This close contact lets the cat feel the owner's care and warmth, simultaneously expressing trust and affection for the owner. Figure 3 A cat curled up with its owner
International Journal of Molecular Zoology 2024, Vol.14, No.1, 1-8 http://animalscipublisher.com/index.php/ijmz 5 Intimate physical contact is a particularly warm and meaningful behavior in the realm of cat communication. Through this means, cats express their affection and attachment to one another and reinforce their deep emotional bonds with humans. Understanding and respecting this form of tactile communication can strengthen the relationship between humans and cats, creating a more harmonious and warm communication environment. In conclusion, cats communicate their emotions and intentions through postures, olfaction, and tactile interactions. Whether it's conveying friendliness, vigilance, closeness, or relaxation, these communication methods enrich the social world of cats and provide humans with an opportunity for a deeper understanding. Understanding these communication methods while interacting with cats can help establish more harmonious relationships. 2 Cognitive Abilities of Cats Cats are a group of animals with remarkable cognitive abilities, and in their daily social and survival activities, they display various cognitive skills. From keen olfactory perception to emotional cognition (Vitale Shreve and Udell, 2015), cats process information in their unique way, adapt to environmental changes, and establish profound emotional connections with humans. This review will delve into the cognitive abilities of cats, including olfactory sensitivity, spatial perception, problem-solving, and emotional cognition. 2.1 Olfactory sensitivity Cognitive abilities play a crucial role in the lives of cats, with olfactory sensitivity being a noteworthy feature. Olfaction not only plays an essential role in a cat's perceptual world but also holds significance in their interactions and cognition among themselves. The following will explore the olfactory cognitive capabilities of cats. For cats, olfaction is a highly important sense. They possess highly sensitive olfactory organs capable of detecting subtle changes in odors. Olfaction serves multiple functions in the lives of cats, including locating food, identifying territories, confirming identities, and perceiving changes in their environment (Crowell-Davis et al., 2004) (Figure 4). Olfaction also assists cats in finding potential mates, understanding the emotional states of other cats, and sensing potential dangers. Therefore, olfaction plays an indispensable role in a cat's cognition, affecting their behaviors in social interactions and survival. Figure 4 Sniffing cat Cats use olfactory recognition to perceive each other's identities, emotions, and states. Each cat has a unique scent determined by the chemical substances they secrete from their bodies. When a cat licks or engages in behaviors like cheek rubbing with another cat, they are, in fact, exchanging scent information, enabling them to recognize one another. Furthermore, cats can identify the identities and emotional states of other cats by sniffing urine, feces, and other excretions. Olfactory abilities also allow cats to discern the freshness of food and even perceive the emotional states of their human companions, deepening the emotional connection between cats and humans. The olfactory sensitivity of cats plays a vital role in their cognition. Olfaction not only helps cats acquire information about the world around them but also assists them in establishing connections in social interactions,
International Journal of Molecular Zoology 2024, Vol.14, No.1, 1-8 http://animalscipublisher.com/index.php/ijmz 6 recognizing the identities, emotions, and states of other cats. A deeper understanding of a cat's olfactory cognitive abilities can enable owners to better meet their needs, provide suitable environments, and enhance understanding and communication between humans and cats. 2.2 Spatial perception Spatial perception is an important component of a cat's cognitive abilities, with their sensitivity to territories and the environment playing a crucial role in their lives. Cats adapt to changes in their environment through perceiving and utilizing their surroundings. A cat's innate territorial and environmental sensitivity is a fundamental instinct. Cats are highly territorial animals, preferring to establish their territories in specific areas and guarding them. This territorial perception allows cats to recognize which areas belong to them and which belong to other cats. They mark their territory with their scent through urine, cheek rubbing, and other means, serving as a warning to other cats not to intrude. Cats are also very sensitive to changes in their territories, allowing them to detect if the scents of other cats have entered their territory and take action when necessary. Spatial perception enables cats to adapt to changes in their environment, whether it's the expansion of their territory or alterations in the external environment. Cats use their territorial perception to plan their actions, deciding when to enter specific areas and when to remain vigilant. When cats perceive the scents of other cats, they may take action to defend their territory. On the other hand, cats can also use spatial perception to adapt to changes in the environment, such as during household relocations or the introduction of new pets. They gradually adapt to new environments by exploring new areas, marking their scent, and observing the reactions of other cats. The spatial perception of cats not only helps them maintain their territories but also enables them to adapt to ever-changing environments. By perceiving and analyzing their surroundings, cats can make appropriate decisions to protect their territories and survival. A deeper understanding of a cat's spatial perception abilities can help create a suitable living environment for them, allowing cats to adapt to changes more effectively and maintain their roles in social interactions. 2.3 Problem-solving abilities Problem-solving abilities are a significant aspect of a cat's cognitive skills, and they often exhibit a tendency to independently solve problems, even using parts of their bodies such as their paws and mouths as tools to resolve challenges. This ability not only demonstrates their intelligence but also reflects their flexibility in adapting to complex environments and dealing with various challenges. Cats are naturally inclined to independently solve problems. When faced with puzzles, they prefer to rely on their own abilities to find solutions rather than seeking help from other cats or humans. This independence is evident in their behaviors, such as when searching for food, exploring their environment, or reaching elevated places, where cats use their efforts to overcome obstacles and showcase their problem-solving abilities. This independent problem-solving ability is especially crucial in the wild for hunting and survival. When solving problems, cats often use parts of their bodies like their paws and mouths as tools. For example, when they need to open door handles, move light objects, or access food, cats may use their paws to pull, push (Figure 5), or use their mouths to pick up and move objects. This behavior indicates that cats not only have the ability to analyze problems but also can determine when and how to use different body parts to solve them. Research has also found that cats may employ various strategies when solving problems based on the specific situation, showcasing their intelligence and flexibility. While cats are less likely to seek human assistance compared to other animals like dogs, their problem-solving abilities remain highly remarkable. Cats exhibit independent problem-solving abilities when confronted with various challenges and issues, utilizing their intelligence and body parts to find suitable solutions. The existence of this ability not only enriches people's understanding of cat cognitive abilities but also demonstrates their powerful potential as social animals in adapting to their environment and overcoming challenges.
International Journal of Molecular Zoology 2024, Vol.14, No.1, 1-8 http://animalscipublisher.com/index.php/ijmz 7 Figure 5 A cat scratching with its claws 2.4 Emotional cognition Emotional cognition is a significant aspect of a cat's cognitive abilities, with their high sensitivity to their owner's emotions and their ability to express joy, anger, sorrow, and other emotions through cognitive behaviors being noteworthy research topics. Studies indicate that cats have the capacity to discern emotions and moods, perceive changes in human emotions, and respond through their behavior (Turner, 2021). Cats exhibit a considerable sensitivity to changes in their owner's emotions. They can perceive their owner's emotional states, such as joy, anger, or anxiety, and may display different behavioral responses when their owner's emotions fluctuate. For example, when their owner is in a good mood, cats may become more affectionate and active, while during periods of low spirits, they may engage in more comforting behaviors, like staying close to their owner or softly vocalizing. Cats express their joy, anger, sorrow, and other emotions through cognitive behaviors, which can be observed through their posture, expressions, and vocalizations. When cats are content and relaxed, they may assume stretched-out postures and purr, among other signs. Conversely, when cats are displeased or frightened, they may raise their shoulders, bristle their fur, and may even emit growls or hissing. Additionally, cats may choose different resting or hiding spots based on their emotions. Research on emotional cognition helps deepen the understanding of the emotional communication between cats and humans, providing insights into their inner world. Cats can sensitively perceive emotional changes and respond through appropriate behaviors, which enables them to better adapt to and interact with humans (Bradshaw et al., 2012). As social animals, cats communicate and express themselves through various means, including sounds, postures, olfaction, and physical contact. They possess the ability to discern emotions and moods, are sensitive to their owner's emotional changes, and express joy, anger, sorrow, and other emotions through cognitive behaviors. This array of complex cognitive and communicative methods enriches our understanding of cat cognition and behavior patterns, while also deepening the emotional bond between humans and cats. 3 Conclusion Cats are truly remarkable animals that have developed a rich and diverse social communication system through various means, including sounds, body language, olfaction, and physical contact. Their cognitive abilities allow them to display remarkable intelligence and adaptability in social interactions, survival, and environmental adaptation. This review delves into the ways cats communicate and their cognitive abilities, revealing how they interact with humans and other cats, as well as how they adapt to their environments and form emotional bonds through cognitive behaviors. In social communication, cats use vocalizations to express a wide range of emotions and needs. Sounds such as purring, meowing, hissing, and growling convey a cat's emotional state, allowing people to better understand their
International Journal of Molecular Zoology 2024, Vol.14, No.1, 1-8 http://animalscipublisher.com/index.php/ijmz 8 inner world. Body postures and movements also play a vital role in feline communication, with behaviors like body rubbing, shoulder raising, and stretching conveying messages of friendliness, alertness, and relaxation. Furthermore, olfactory communication helps cats identify identities and emotions, playing a significant role in social interactions, such as cheek rubbing used for marking territory and expressing affection. Cats' cognitive abilities are crucial in adapting to different environments. Their acute sense of smell allows them to detect subtle changes in odors, providing insights into their surroundings and other animals. Spatial awareness enables cats to quickly identify territorial boundaries and the presence of other cats while helping them adjust to new environments. Cats exhibit problem-solving skills by independently using their bodies to find solutions, which is especially important in their natural hunting and survival. Emotional cognition allows cats to perceive their owner's emotions and express joy, anger, sadness, and relaxation through cognitive behaviors, strengthening emotional bonds. In summary, as social animals, cats have developed a diverse communication system that enables them to form close connections with other cats and humans through various means. Their cognitive versatility allows them to adapt flexibly to different environments, independently solve problems, and establish deeper emotional connections with humans. By gaining a deeper understanding of cat communication and cognitive abilities, humans can better coexist with cats, providing them with a home filled with understanding and care. Author’s contributions XMY was responsible for conducting literature research, organizing, and writing the initial draft of this review. I have read and agreed to the final text. Acknowledgments I would like to express my gratitude to Ms. LMT for providing valuable and targeted feedback during the revision of my paper. References Bernstein P.L., 2007, The human-cat relationship, In: Rochlitz I. (ed.), The welfare of cats, Springer, Berlin, Germany, pp.47-89. https://doi.org/10.1007/978-1-4020-3227-1_3 Bradshaw J.W.S., Casey R.A., and Brown S.L., eds., 2012, The behaviour of the domestic cat, CABI, London, UK, pp.161-174. https://doi.org/10.1079/9781845939922.0161 Crowell-Davis S.L., Curtis T.M., and Knowles R.J., 2004, Social organization in the cat: a modern understanding. J. Feline Med. Surg., 6: 19-28. https://doi.org/10.1016/j.jfms.2003.09.013 McComb K., Taylor A.M., Wilson C., and Charlton B.D., 2009, The cry embedded within the purr, Curr. Biol., 19(13): R507-R508. https://doi.org/10.1016/j.cub.2009.05.033 Saito A., and Shinozuka K., 2013, Vocal recognition of owners by domestic cats (Felis catus), Anim. Cogn., 16(4): 685-690. https://doi.org/10.1007/s10071-013-0620-4 Turner D.C., and Bateson P., eds., 2014, The domestic cat: The biology of its behaviour, 3rd edition, Cambridge University Press, Cambridge, UK, pp.71-80. Turner D.C., 2021, The mechanics of social interactions between cats and their owners, Front. Vet. Sci., 8: 650143. https://doi.org/10.3389/fvets.2021.650143 Vitale K., 2022, Normal feline social behavior, In: Stelow E. (ed.), Clinical handbook of feline behavior medicine, John Wiley & Sons, Inc., Hoboken, USA, pp.10-21. https://doi.org/10.1002/9781119653271.ch2 Vitale Shreve K.R., and Udell M.A.R., 2015, What's inside your cat's head? A review of cat (Felis silvestris catus) cognition research past, present and future, Anim. Cogn., 18: 1195-1206. https://doi.org/10.1007/s10071-015-0897-6 Yeon S.C., Kim Y.K., Park S.J., Lee S.S., Lee S.Y., Suh E.H., Houpt K.A., Chang H.H., Lee H.C., Yang B.G., Lee H.J., 2011, Differences between vocalization evoked by social stimuli in feral cats and house cats, Behav. Processes, 87(2): 183-189. https://doi.org/10.1016/j.beproc.2011.03.003
International Journal of Molecular Zoology 2024, Vol.14, No.1, 9-17 http://animalscipublisher.com/index.php/ijmz 9 Research Article Open Access Applications of Mouse Gene Editing Technology in the Treatment of Hereditary Blindness Zhenni Lu Hangzhou Luohuashi Biotechnology Co., Ltd, Hangzhou, 310000, China Corresponding author email: 1348509309@qq.com International Journal of Molecular Zoology, 2024, Vol.14, No.1 doi: 10.5376/ijmz.2024.14.0002 Received: 09 Nov., 2023 Accepted: 22 Dec., 2023 Published: 10 Jan., 2024 Copyright © 2024 Lu, This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Preferred citation for this article: Lu Z.N., 2024, Applications of mouse gene editing technology in the treatment of hereditary blindness, International Journal of Molecular Zoology, 14(1): 9-17 (doi: 10.5376/ijmz.2024.14.0002) Abstract This study explores the applications of mouse gene editing techniques in the research and treatment of hereditary blindness. Mouse models serve as ideal tools for biomedical research and possess significant advantages such as genetic similarity to humans, rapid growth and reproduction, abundant genetic tools, and controllable laboratory environments. Gene editing techniques, particularly CRISPR/Cas9, have made significant breakthroughs, enabling scientists to simulate genetic mutations related to inherited blindness, validate treatment strategies, conduct drug screening, and explore disease mechanisms. Implemented cases of mouse gene editing treatments, such as the restoration of Leber's hereditary optic neuropathy (LHON) and the regeneration of retinal cells, offer new hope for the treatment of hereditary blindness. While mouse gene editing treatments still face challenges, including ensuring safety and therapeutic efficacy, it holds enormous potential for clinical translation. Ethical considerations, targeting accuracy, cell toxicity, immune responses, and post-treatment effects are also crucial factors that need careful consideration. In conclusion, mouse gene editing techniques provide powerful tools for research in the treatment of hereditary blindness, offering new hope for future therapies. Keywords Mouse models; Gene editing techniques; Hereditary blindness; CRISPR/Cas9; Ethical considerations Hereditary blindness is a severe visual impairment typically caused by mutations in disease-associated genes, impacting the quality of life for millions of individuals globally. These genetic mutations can affect various aspects, including visual signal transduction, retinal structure and function, and optic nerve development, resulting in different types of hereditary blindness (Cremers et al., 2018). Patients may face the risk of blindness from birth or experience the onset of blindness in their youth or adulthood. Hereditary blindness imposes significant physical and psychological burdens on patients and their families, underscoring the crucial need for research and the development of therapeutic approaches. In recent years, the rapid advancement of gene editing technologies has provided new hope for the treatment of hereditary blindness. In this context, mouse models have become essential tools for studying the mechanisms and therapeutic strategies for hereditary blindness. Mice share a similar visual system structure and function with humans while having a shorter lifespan, facilitating experimental research (Liu et al., 2022). Through gene editing technologies, researchers can simulate pathogenic mutations causing hereditary blindness and test different treatment approaches, offering valuable insights for future therapeutic strategies. The objective of this study is to explore the application of mouse gene editing technology in the treatment of hereditary blindness. By reviewing the molecular basis of hereditary blindness, discussing the importance of mouse models, providing a detailed overview of the development and application of gene editing technology, examining the application of different gene editing techniques, and highlighting specific applications of mouse gene editing technology in the treatment of hereditary blindness (Ma and Liu, 2022). Finally, this study will pay attention to the ethical and safety considerations of gene editing technology, emphasizing the safety and potential risks of treatment. This research aims to provide readers with a comprehensive understanding of the latest developments and prospects of mouse gene editing technology in the treatment of hereditary blindness, offering robust support for future research and clinical applications.
International Journal of Molecular Zoology 2024, Vol.14, No.1, 9-17 http://animalscipublisher.com/index.php/ijmz 10 1 Molecular Basis of Hereditary Blindness 1.1 Common genetic mutations and pathogenic genes in hereditary blindness SHereditary blindness comprises a group of rare diseases caused by genetic mutations, and its incidence varies with different types of genetic alterations. In the investigation of the molecular basis of hereditary blindness, some common genetic mutations and pathogenic genes have been identified. A prevalent form of hereditary blindness is cone-rod dystrophy (CRD). This condition is often associated with mutations in the RHO gene, which encodes opsin and plays a crucial role in the visual transduction process. Similar diseases include retinitis pigmentosa (RP) (Figure 1), caused by mutations in various genes such as RHO, RPGR, and RP1 (Böhm et al., 2020). Mutations in these genes result in damage to rod and cone cells, ultimately leading to blindness. Figure 1 BR clinical manifestations (Source: Wikipedia) Leber's hereditary optic neuropathy (LHON) is another hereditary blindness disease typically caused by mutations in mitochondrial genes such as MT-ND1, MT-ND4, and MT-ND6. These genes encode subunits of the mitochondrial respiratory chain complex, and their mutations impair mitochondrial function, triggering degenerative damage to the optic nerve. Retinal pigment epithelium dystrophy (RPED) is a group of diseases often involving mutations in the RPE65 gene. RPE65 encodes a crucial enzyme in the retinal pigment epithelial cells, maintaining the balance of vitamin A metabolism in the visual cycle. Mutations in the RPE65 gene result in the loss of function in retinal pigment epithelial cells, affecting visual function. 1.2 Exploring the biological mechanisms of hereditary blindness Understanding the molecular basis of hereditary blindness requires an in-depth study of the biological mechanisms related to visual transduction. Visual transduction is a highly complex process involving multiple cell types and signaling pathways. The visual process begins with rod and cone cells in the retina, containing visual pigments that can sense light and convert it into neural signals. Mutations in visual pigments affect the quality of light perception; therefore, CRD and RP caused by RHOgene mutations, as well as RPED caused by RPE65 gene mutations, are associated with visual pigment dysfunction. The optic nerve is a critical site for transmitting light signals to the brain, and LHON is linked to the loss of mitochondrial function. Mitochondria play a vital role in cellular energy production, crucial for optic nerve conduction. Mutations in MT-NDgenes affect the function of mitochondrial complexes, resulting in reduced energy production and damage to optic nerve cells.
International Journal of Molecular Zoology 2024, Vol.14, No.1, 9-17 http://animalscipublisher.com/index.php/ijmz 11 On the other hand, retinal pigment epithelial cells is also crucial for the maintenance of visual function. The enzyme encoded by the RPE65 gene plays a critical role in the metabolism of retinaldehyde in the retina, helping the retina maintain the homeostasis of vitamin A. Mutations in RPE65 disrupt vitamin A metabolism, ultimately leading to RPED. Therefore, a profound understanding of these biological mechanisms is crucial for the treatment of hereditary blindness. The molecular basis research of hereditary blindness lays the foundation for the development of gene editing therapies, allowing interventions specific to particular genetic mutations. It is hoped that this therapeutic approach will bring new hope to individuals affected by blindness. 2 Importance of Mouse Models 2.1 Introduction to the advantages of mice as biomedical research models Mice serve as widely utilized models in the scientific community for biomedical research, owing to their numerous advantages. Mice share a significant genetic resemblance with humans, with many genes exhibiting similar functions and structures in both species. This genetic similarity makes mice an ideal model for studying human diseases. In the investigation of hereditary blindness, the genetic similarity of mice plays a crucial role in understanding the mechanisms behind relevant genetic mutations (Gurumurthy and Lloyd, 2019). Mice exhibit rapid growth and have a short reproductive cycle, enabling scientists to conduct large-scale experiments and breed a substantial number of experimental animals within a relatively short timeframe. This is particularly important for the study of hereditary blindness, as it involves the analysis of gene mutations and the validation of therapeutic approaches. Research on mouse models benefits from a rich array of genetic tools, including various gene-editing technologies, mutant mouse libraries, and tools for analyzing genetic alterations (Figure 2). These tools empower researchers to precisely manipulate mouse genes, facilitating the study of genetic variations related to blindness. Mouse experiments can be easily conducted in controlled laboratory environments, allowing researchers to adjust factors such as temperature, light exposure, diet, and other variables to simulate different physiological conditions. This is crucial for studying the influencing factors of hereditary blindness. Figure 2 Mouse model (Source: Wikipedia) 2.2 Discussion on the application of mouse models in hereditary blindness research Mouse models play a crucial role in the study of hereditary blindness, providing valuable information and opportunities to understand disease mechanisms and develop treatment methods. By introducing specific genetic mutations or mutant mouse models, scientists can simulate different types of hereditary blindness, such as retinitis pigmentosa degeneration and hereditary cataracts. These models contribute to the study of blindness mechanisms, identification of key factors leading to blindness, and exploration of potential therapeutic targets. Mouse models are also employed to validate the effectiveness of gene therapy strategies. Scientists can use gene-editing
International Journal of Molecular Zoology 2024, Vol.14, No.1, 9-17 http://animalscipublisher.com/index.php/ijmz 12 techniques to repair or replace critical genes, restoring visual function in mice. This provides a robust foundation for the development of potential genetic therapeutic approaches. In mouse models, researchers can conduct drug screening experiments to identify potential drug treatment options. These trials help evaluate the efficacy of different drugs in alleviating blindness symptoms, providing crucial information for clinical treatments. Optogenetics, a method based on light-sensitive proteins, is used to control neuronal activity. Mouse models play a vital role in optogenetic research, aiding in the understanding of the visual system's functionality and the development of new therapeutic approaches. Blindness involves not only damage to retinal cells but also requires neuroprotective strategies. Mouse models are employed to study the effectiveness of neuroprotective methods to slow down or halt the progression of blindness. In conclusion, mouse models play a crucial role in hereditary blindness research, offering researchers opportunities to gain in-depth insights into blindness mechanisms and test potential therapeutic methods. Combined with advanced tools such as gene-editing technologies, mouse models hold the promise of bringing new breakthroughs in the treatment of hereditary blindness. 3 Development and Application of Gene Editing Technologies 3.1 Overview of CRISPR/Cas9 gene editing technology and its principles Since its inception, the CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats/Cas9) gene editing technology has garnered widespread attention and sparked a revolution in the scientific community. This technology allows scientists to precisely modify gene sequences, providing a powerful tool for researching genetic diseases and exploring gene therapy. The principle of CRISPR/Cas9 is based on a bacterial defense mechanism found in the natural immune system, which can identify and cut the genome of invading viruses. CRISPR represents a series of short DNA sequences, while Cas9 is an enzyme capable of cutting DNA. During the gene editing process, researchers design a CRISPR guide RNA that can recognize specific gene sequences. Once the CRISPR guide RNA matches the target gene, the Cas9 enzyme is activated to cut the target DNA. Cells then attempt to repair the cut DNA, usually through non-homologous end joining (NHEJ) or homology-directed repair (HDR). These repair processes may result in gene mutations, achieving the goal of gene editing (Figure 3). Figure 3 Gene editing process (Source: Wikipedia)
International Journal of Molecular Zoology 2024, Vol.14, No.1, 9-17 http://animalscipublisher.com/index.php/ijmz 13 The advantages of CRISPR/Cas9 lie in its simplicity and efficiency, enabling researchers to precisely edit mouse genes to simulate and study gene mutations associated with hereditary blindness. 3.2 Discussion on the methods and results of applying CRISPR/Cas9 in mouse models Significant progress has been made in applying CRISPR/Cas9 technology in mouse models, providing robust support for the study and treatment of hereditary blindness. Mice are commonly used experimental animal models due to their biological similarities to humans, making the application of CRISPR/Cas9 particularly beneficial in mice. Through CRISPR/Cas9, researchers can accurately simulate gene mutations associated with hereditary blindness in mouse models. They can select target genes, design corresponding CRISPR guide RNAs, and introduce the Cas9 enzyme into mouse embryos. This approach has been successfully used to simulate various hereditary blindness diseases, such as retinitis pigmentosa, familial cataracts, and glaucoma (Liu et al., 2023). By observing the behavior and molecular changes in mice, researchers can gain in-depth insights into the pathogenesis of these diseases. Furthermore, CRISPR/Cas9 can be used to develop new therapeutic approaches. By repairing or replacing damaged genes, scientists can attempt to correct gene mutations associated with hereditary blindness. In mouse models, these therapeutic strategies have shown potential, although further research and optimization are still required. 3.3 Discussion on the application of other gene editing technologies In addition to CRISPR/Cas9, there are other gene editing technologies that can be applied to the study of hereditary blindness in mouse models. The most notable ones include zinc finger nucleases (ZFNs) and transcription activator-like effector nucleases (TALENs). These technologies are also targeted, allowing researchers to edit mouse genes. ZFNs use zinc finger proteins to guide the cutting of specific DNA sequences, while TALENs use engineered proteins to achieve the same goal. Although their principles and application methods differ from CRISPR/Cas9, they still provide effective gene editing tools. In mouse models, these technologies have been used to simulate hereditary blindness and have demonstrated similar potential to CRISPR/Cas9. The choice of these methods depends on the specific needs and experimental conditions of researchers. Sometimes, different gene editing technologies can complement each other for a more comprehensive study. It should be noted that different gene editing technologies differ in efficiency, specificity, and complexity. Therefore, when choosing the most suitable technology, researchers need to balance these factors. In the context of studying hereditary blindness, gene editing technologies such as CRISPR/Cas9, ZFNs, and TALENs provide scientists with various tools to better understand the pathogenesis of hereditary blindness and explore new treatment strategies. The application of these technologies is expected to bring more hope to blind patients. Although further research and clinical validation are still needed, they have paved the way for the future treatment of hereditary blindness. 4 Mouse Gene Editing Technology in the Treatment of Hereditary Blindness 4.1 Introduction to implemented cases of mouse gene editing therapy In the treatment of hereditary blindness, mouse models have become an ideal choice for studying gene editing technology due to their unique advantages. There have been some exciting cases of mouse gene editing therapy, bringing new hope to the treatment of hereditary blindness. One notable case is the study on Leber's hereditary optic neuropathy (LHON) (Yu et al., 2018). LHON is a genetic eye disorder associated with mitochondrial dysfunction, leading to acute vision loss. Researchers successfully
International Journal of Molecular Zoology 2024, Vol.14, No.1, 9-17 http://animalscipublisher.com/index.php/ijmz 14 used CRISPR/Cas9 technology to repair the mutated genes in a mouse model of LHON. This study demonstrates that gene editing technology can correct genetic eye disorders in mice, providing a promising approach for clinical treatment. Another important case involves the regeneration of retinal cells. Retinal cells are crucial cells in the visual process, and their damage can lead to blindness. Researchers used gene editing technology to activate regeneration-related genes in the mouse retina, successfully restoring the visual function of blind mice. This case provides strong support for applying gene editing technology to the treatment of hereditary blindness, especially in diseases related to the retina. 4.2 Discussion of treatment methods, results, and potential limitations Mouse gene editing therapy typically involves using CRISPR/Cas9 technology or other gene editing tools to repair or replace damaged genes in the patient's body. The application of these treatment methods in mouse models usually requires several steps. Researchers first identify the gene mutations causing blindness and then design CRISPR guide RNA to precisely locate and repair these mutations. This often involves in-depth molecular biology research and gene sequencing. Researchers introduce the CRISPR/Cas9 complex into mouse embryos to precisely cut and modify the damaged genes. This may require optimization to ensure efficient editing and minimal non-specific damage. Once the genes are edited, damaged cells can restore normal function through self-repair or regeneration. This may take time, and not all cells can successfully repair. Treatment outcomes typically require long-term tracking and evaluation in mouse models. These outcomes include the restoration of visual function (Figure 4), cellular pathological changes, and the repair of genetic mutations. Figure 4 Visual function recovery process However, mouse gene editing therapy also faces some potential limitations. Firstly, there are biological and genetic differences between mouse models and humans, so the efficacy of treatment needs validation in more suitable animal models before clinical translation. Secondly, the safety and precision of gene editing technology need further research to ensure no adverse consequences. Additionally, the cost and complexity of treatment are potential limitations that need to be addressed for widespread application.
RkJQdWJsaXNoZXIy MjQ4ODY0NQ==