Junwei Chen, Yudi Zhao, Nan Li, Hui Wang, Xuesong Wu, Baichang Wang, Xin Wei, Yaqing Chang, Yi Tian
Elucidate the molecular salinity response mechanisms in Apostichopus japonicus, focusing on miRNA-mediated regulation and core pathways, highlighting a hierarchical network in which 8 key miRNAs fine-tune responses. let-7 targeted Solute Carrier Family 34 Member 2 (SLC34A2) and Cystathionine Gamma-Lyase (CTH), coordinating ion transport and amino acid metabolism, respectively; miR-10 targeted genes Nicotinamide Phosphoribosyltransferase (NAMPT) in energy homeostasis and TGF-Beta Activated Kinase 1 (MAP3K7) Binding Protein 1 (Table 1) to regulate MAPK/ERK signaling. Salinity sensing initiates GPCR-mediated cAMP/PKA and MAPK/ERK cascades, activating transcription factors (UBTF) to drive stress gene expression; ion transporters (SLC family), ABC transporters, and vesicular transport maintain cellular homeostasis.
Salinity fluctuations pose critical physiological challenges to the sea cucumber Apostichopus japonicus. This review elucidated its molecular salinity response mechanisms, focusing on miRNA-mediated regulation and core pathways. We highlight a hierarchical network in which 8 key miRNAs fine-tune responses. let-7 targeted Solute Carrier Family 34 Member 2 (SLC34A2) and Cystathionine Gamma-Lyase (CTH), coordinating ion transport and amino acid metabolism, respectively. miR-10 targeted genes Nicotinamide Phosphoribosyltransferase (NAMPT) in energy homeostasis and TGF-Beta Activated Kinase 1 (MAP3K7) Binding Protein 1 (Table 1) to regulate MAPK/ERK signaling. miR-278-3p targeted 5-Hydroxytryptamine Receptor 2B (Htr2b) and Chloride Channel Accessory 1 (CLCA1) to modulate GPCR signaling and chloride transport. miR-2008, miR-3, miR-16, miR-22, and miR-14 coordinate vesicular trafficking, transcription, apoptosis, and autophagy via targeting Pleckstrin Homology Domain Containing A3 (PLEKHA3), Upstream Binding Transcription Factor (UBTF), ATP Binding Cassette Subfamily C Member 2 (ABCC2), Polypeptide N-Acetylgalactosaminyltransferase 2 (GALNT2), Glutamic-Oxaloacetic Transaminase 2 (Got2), Aconitase 2 (Aco2), and RNA Polymerase II Associated Protein 2 (Rpap2). Salinity sensing initiates GPCR-mediated cAMP/PKA and MAPK/ERK cascades, activating transcription factors (UBTF) to drive stress gene expression. Ion transporters (SLC family), ABC transporters, and vesicular transport maintain cellular homeostasis. Cullin Associated and Neddylation Dissociated 1 (CAND1)/Listerin E3 ubiquitin protein ligase 1 (Ltn1) are involved in amino acid/protein metabolism and ubiquitinated proteins to participate in vesicular transport for protein sorting and secreting. These secreted molecules (Glyare/Taurine) act as ligands to bind membrane receptors and trigger GPCR pathways and energy metabolism and redox balance. Aco2/Got2/NAMPT supply ATP for adaptation and apoptosis/autophagy, repair damage and maintain homeostasis, alleviate oxidative damage, supported by innate immunity genes. These findings establish a framework for understanding sea cucumbers salinity adaption, further exploration of additional genes is needed to refine mechanistic details.