The 2024 Nobel Prize in Physiology or Medicine has been awarded to two pioneering researchers, Victor Ambros and Gary Ruvkun, marking the fourth time research using Caenorhabditis elegans (C. elegans) has received this prestigious recognition. With a rapid life cycle of just 3.5 days and four distinct larval stages, C. elegans serves as an ideal model for exploring complex genetic mechanisms, particularly heterochronic gene regulation. Ambros and Ruvkun's groundbreaking work on lin-4 and lin-14 genes in C. elegans revealed that lin-4 functions as a 22-nucleotide small RNA-now known as a microRNA (miRNA)-that binds complementarily to the 3' UTR of lin-14 mRNA, effectively inhibiting LIN-14 protein synthesis. This discovery was the first demonstration of miRNA in post-transcriptional gene regulation, a finding that has since reshaped our understanding of genetic regulation across species. Their research on small RNAs in C. elegans not only opened a new paradigm in molecular biology but also highlighted the power of this model organism in uncovering universal biological principles.