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bioRxiv · 10.1101/2021.10.06.463443

seRNA PAM-1 regulates skeletal muscle satellite cell activation and aging through trans regulation of Timp2 expression synergistically with Ddx5

Abstract

Muscle satellite cells (SCs) are responsible for muscle homeostasis and regeneration; and lncRNAs play important roles in regulating SC activities. Here in this study, we identify PAM-1 (Pax7 Associated Muscle lncRNA) that is induced in activated SCs to promote SC activation into myoblast cells upon injury. PAM-1 is generated from a myoblast specific super-enhancer (SE); as a seRNA it binds with a number of target genomic loci predominantly in trans. Further studies demonstrate that it interacts with Ddx5 to tether PAM-1 SE to it inter-chromosomal targets Timp2 and Vim to activate the gene expression. Lastly, we show that PAM-1 expression is increased in aging SCs, which leads to enhanced inter-chromosomal interaction and target genes up-regulation. Altogether, our findings identify PAM-1 as a previously unknown lncRNA that regulates both SC activation and aging through its trans gene regulatory activity.

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So, K. K. H., Huang, Y., Zhang, S., He, L., Li, Y., Chen, X., Zhao, Y., Ding, Y., Zhou, J., Yuan, J., Sham, M. H., Sun, H., Wang, H.. 2021-10-07. seRNA PAM-1 regulates skeletal muscle satellite cell activation and aging through trans regulation of Timp2 expression synergistically with Ddx5. https://doi.org/10.1101/2021.10.06.463443

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