Loading...
Thumbnail Image
Publication

Skeletal muscle differentiation drives a dramatic downregulation of RNA polymerase III activity and differential expression of Polr3g isoforms

McQueen, Caitlin
Hughes, Gideon L.
Pownall, Mary Elizabeth
Advisors
Editors
Other Contributors
EPub Date
Publication Date
2019-10-01
Submitted Date
Other Titles
Abstract
Gene regulatory networks underpinning skeletal muscle determination and differentiation have been extensively investigated, providing molecular insights into how cell lineages are established during development. These studies have exclusively focused on the transcriptome downstream of RNA polymerase II (Pol II). RNA polymerase III (Pol III) drives the production of tRNAs and other small RNAs essential for the flow of genetic information from gene to protein and we have found that a specific isoform of a subunit unique to Pol III is expressed early in the myogenic lineage. This points to the possibility that additional regulatory networks exist to control the production of Pol III transcripts during skeletal muscle differentiation. We describe the differential expression of Polr3g and its alternate isoform Polr3gL during embryonic development and using a custom tRNA microarray, we demonstrate their distinct activity on the synthesis of tRNA isoacceptors. We show that Pol III dependent transcripts are dramatically down-regulated during the differentiation of skeletal muscle, as are mRNAs coding for Pol III associated proteins Brf1 and Brf2, while Polr3gL is up-regulated alongside contractile protein genes. Forcing Polr3g expression in this context results in a partial reversal of myogenic differentiation.
Citation
McQueen, C., Hughes, G. L., & Pownall, M. E. (2019). Skeletal muscle differentiation drives a dramatic downregulation of RNA polymerase III activity and differential expression of Polr3g isoforms. Developmental biology, 454(1), 74-84. https://doi.org/10.1016/j.ydbio.2019.06.001
Publisher
Elsevier
Journal
Developmental Biology
Research Unit
DOI
10.1016/j.ydbio.2019.06.001
PubMed ID
PubMed Central ID
Type
Article
Language
Description
Series/Report no.
ISSN
0012-1606
EISSN
ISBN
ISMN
Gov't Doc
Test Link
Sponsors
Additional Links
https://www.sciencedirect.com/science/article/pii/S001216061930106X?via%3Dihub