PME Distinguished Colloqium: Dr. Haifan Lin

Post-Transcriptional Regulation of Stem Cells by Coding and Noncoding RNAs

Stem cells maintain their balance between self-renewal and differentiation through precise gene regulation. While transcriptional control is well studied, post-transcriptional regulation remains less explored. This talk highlights two key post-transcriptional mechanisms. First, RNA-binding Pumilio proteins (Pum1 and Pum2) play distinct roles in embryonic stem cells (ESCs) and early development. Pum1 promotes differentiation, while Pum2 supports self-renewal, forming a regulatory loop affecting over 700 mRNAs. Pum1/2 double mutant ESCs show impaired self-renewal and differentiation, and mutant mice exhibit developmental delays and embryonic lethality. Second, Piwi-interacting RNAs (piRNAs) and Piwi proteins mediate genome-wide post-transcriptional regulation. These pathways control gene expression, transposons, and noncoding RNAs, crucial for germline fate and stem cell maintenance. These findings emphasize the significance of post-transcriptional regulation in stem cell biology, revealing novel mechanisms that sustain pluripotency and differentiation.

Hosted By: Prof. Joyce Chen