Integrative transcriptome and metabolome analyses reveal molecular mechanisms of tail resorption in Fejervarya...

Tail resorption is a hallmark of amphibian metamorphosis, yet the underlying molecular mechanisms remain incompletely understood. To address these deficiencies, we integrated morphological, histological, transcriptomic, and metabolomic analyses to explore tail resorption in Fejervarya multistriata. Tadpole tail regressed during metamorphosis, whereas the limbs gradually developed to maturity. Correspondingly, the expression levels of genes encoding motor proteins were lower in the tail than in the hindlimbs, supporting a functional shift from tail to limb locomotion. Tail resorption is driven by three cellular processes: MMP mediated ECM degradation, autophagy, and apoptosis. Our transcriptomic analysis revealed key regulatory genes involved in these processes, including ECM-related genes (mmp9, mmp14, and mmp18), autophagy-related genes (atg4, gabarap, atg12, and atg16l), and apoptosis-related genes (bid, bax, apaf1, casp7, and casp9). Metabolomic data indicated palmitoylcarnitine and pAzPC as potential apoptosis indicators. Overall, our findings offer insights into the molecular basis of tail resorption and provide a multi-omics resource that will facilitate future studies of this process.