International Journal of Aquaculture, 2025, Vol.15, No.1, 29-36 http://www.aquapublisher.com/index.php/ija 31 growth. GH is secreted by the pituitary gland and promotes the synthesis and secretion of IGF-1 by promoting the liver and peripheral tissues, thereby stimulating the growth of muscles and other tissues. In bony fish, studies have confirmed that the GH/IGF system has an important regulatory effect on growth (Qing et al., 2024). For example, the triploid crucian carp study showed that the expression levels of GH, GH receptor (GHR) and IGF-1 genes in vigorously grown individuals suggest that enhanced GH/IGF axis activity can promote rapid growth of fish. In muscle, IGF-1 mediates the activation of signaling pathways such as PI3K/AKT through GHR, increasing protein synthesis and satellite cell proliferation, thereby accelerating muscle fiber growth. Therefore, gene variation or expression differences in the GH/IGF axis may directly affect the growth rate and final body shape of bamboo shoots. 3.2 Myogenic regulatory factors (MRFs) Myogenic regulators (MRFs) include transcription factor families such as Myf5, MyoD, Myogenin and MRF4, which play a central role in the differentiation and formation of muscle cells. These factors initiate transcriptional procedures of muscle-related genes by binding to specific DNA sequences, driving myoblasts to differentiate into mature myofibers. Research points out that MyoD family members are crucial in the muscle formation process of vertebrates (Kim et al., 2008). In fish, these MRFs are equally highly conserved, able to identify non-myosinutrient cells and induce their transition to myosinutrient cell phenotype. In addition, the expression regulation and interaction of MRFs form a complex network to accurately control the spatiotemporal process of muscle development. There are currently no direct reports for bamboo shoot shellfish, but other fish species studies have shown that changes in MRFs expression will affect the rate of muscle growth and the number of fiber formation, and can be used as candidate targets for genetic breeding improvement. 3.3 Roles of non-coding RNAs such as miRNAs and lncRNAs in muscle development In addition to the above-mentioned coding genes, non-coding RNAs (such as miRNA and lncRNA) are also involved in regulating muscle development. In recent years, studies have found that a large number of miRNAs are expressed in fish muscle development, and typical muscle-specific miRNAs (miR-1, miR-133, miR-206, etc.) can regulate myogenic cells proliferation and differentiation. In addition, some lncRNAs indirectly regulate the expression of muscle-related genes by binding to miRNA or proteins. García-Pérez et al. (2024) showed that in sea bream satellite cells, amino acid-rich and IGF-1-enhancing treatment can change the expression profiles of more than 100 miRNAs (including miR-133a/b, miR-206, etc.) and multiple lncRNAs, and found that 8 lncRNAs are negatively correlated with muscle-specific mRNAs, indicating that these non-coding RNAs may participate in muscle gene regulation through the "sponge" mechanism (García-Pérez et al., 2024). These findings suggest that muscle growth of bamboo shoot shell fish may also be significantly affected by miRNA and lncRNA, revealing a new dimension of gene expression regulation. 4 Genetic Basis of Flesh Quality Traits 4.1 Genes related to fat deposition and intramuscular fat Fish body fat mainly exists in the form of liver, abdominal fat and intramuscular fat. The content of intramuscular fat is considered an important factor affecting the flavor and juiciness of meat. In terms of related genes, the hormone-sensitive lipase (HSL) gene is a key enzyme for fat mobilization, and its expression is closely related to fat storage. In addition, transcription factors such as PPARγ, FABP (fatty acid binding protein) and lipid metabolic enzyme genes are also involved in fish adipogenesis and distribution. Dang et al. (2019) pointed out that "the fat content of fish body and the composition of fatty acids are one of the important criteria for evaluating the quality of fish meat. Studies have shown that increasing the fat content in muscle can effectively improve the taste of meat", emphasizing the importance of intramuscular fat to meat quality. The genetic polymorphism and expression regulation of these genes may explain the differences in intramuscular fat deposition capacity of different strains or varieties, and is also a potential marker for improving fish meat quality. 4.2 Regulatory factors influencing muscle texture and water-holding capacity The texture (hardness, firmness) and water-holding properties of fish are affected by a variety of factors, among which the diameter, number of muscle fibers and connective tissue structure play a major role. Studies have
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