Computational Molecular Biology 2025, Vol.15, No.2, 84-90 http://bioscipublisher.com/index.php/cmb 86 3.2 Key enzymes and genes The generation of Leonurus japonicus alkaloids requires the participation of a series of specific enzymes, which respectively catalyze different reaction links. For instance, during the process of converting primary metabolites into intermediate products, key enzymes play a role. There are usually strictly regulated genes driving behind these enzymes, and external conditions (such as environmental stress or plant hormone signals) often also affect the expression of these genes (Tian et al., 2021). In recent years, some studies have successively identified some genes that play a core role in the synthesis of Leonurus japonicus alkaloids. Most of these genes belong to larger gene families, and these families themselves are related to the synthesis of multiple types of secondary metabolites. It is worth noting that the activity of these genes is often not controlled in isolation; they are regulated by transcription factors. Transcription factors regulate transcriptional levels by binding to promoter regions of genes, thereby affecting the synthetic efficiency of alkaloids (Li et al., 2019a). 3.3 Mechanisms affecting synthesis The formation of motherwort alkaloids is not determined by a single factor, but is the result of the combined effects of genetics, environment and biochemical mechanisms. At the genetic level, the presence of different alleles and the expression levels of genes related to synthesis will both have an impact on the final yield. Some genotypes may promote synthesis, while others may have an inhibitory effect. The external environmental conditions should also not be ignored. For instance, changes in light intensity, temperature and soil nutrients can affect the accumulation of alkaloids by altering the metabolic state of plants (Du et al., 2020). At the biochemical level, the supply of substrates and the activity of key enzymes are important links that determine the amount of products. There is often a substrate competition relationship among different metabolic pathways, which also affects the final yield of alkaloids. Furthermore, some signaling molecules (such as jasmonic acid substances) can induce the expression of related genes, enabling plants to accelerate the accumulation of alkaloids when facing environmental stress or developmental regulation (Jiao et al., 2022). 4 The Regulatory Network of Leonurus japonicus Alkaloid Accumulation 4.1 The role of transcription factors in the synthesis of Leonurus japonicus alkaloids In motherwort, transcription factors (TFs) play a key role in regulating the synthesis of alkaloids. Studies have shown that many transcription factors related to jasmonic acid, especially members from the AP2/ERF, bHLH, MYB and WRKY families, can promote the generation of various secondary metabolites including alkaloids by initiating specific metabolic pathways. Among them, the bHLH transcription factor has been verified in the synthesis of cyanogenic glycosides in Lotus japonicus, and this pathway is closely related to the formation of alkaloids (Chen et al., 2022). These transcription factors can activate the expression of key enzyme genes, thereby promoting the accumulation of alkaloids within the plant. It is worth noting that transcription factors do not "fight alone" among themselves. They often form more complex regulatory networks through interaction. For instance, the WRKY transcription factor has been confirmed to promote the synthesis of phenylisoquinoline alkaloids in Nelumbo nucifera (Li et al., 2022). Furthermore, they may also interact with jasmonic acid-Zirm domain proteins, etc., further increasing the levels and flexibility of regulation. This means that the regulation of alkaloids in motherwort may also follow a similar pattern. 4.2 The influence of plant hormones on the accumulation of alkaloids in Leonurus japonicus The role of plant hormones in the accumulation of Leonurus japonicus alkaloids cannot be ignored. Jasmonic acid (JAs) is one of the most deeply studied ones. It can induce the synthesis of multiple secondary metabolites by activating specific transcription factors (Zhou and Memelink, 2016). For instance, in Leonurus japonicus, jasmonic acid has been proven to regulate cyanoglycoside synthesis, suggesting that it may also play a similar role in the alkaloid metabolism of Leonurus japonicus. Functionally speaking, this regulation is not only for the accumulation of products, but also closely related to the plant's resistance to external stress.
RkJQdWJsaXNoZXIy MjQ4ODYzNA==