Genomic clustering facilitates nuclear processing of suboptimal pri-miRNA loci Journal Article

Authors: Shang, R.; Baek, S. C.; Kim, K.; Kim, B.; Kim, V. N.; Lai, E. C.
Article Title: Genomic clustering facilitates nuclear processing of suboptimal pri-miRNA loci
Abstract: Nuclear processing of most miRNAs is mediated by Microprocessor, comprised of RNase III enzyme Drosha and its cofactor DGCR8. Here, we uncover a hidden layer of Microprocessor regulation via studies of Dicer-independent mir-451, which is clustered with canonical mir-144. Although mir-451 is fully dependent on Drosha/DGCR8, its short stem and small terminal loop render it an intrinsically weak Microprocessor substrate. Thus, it must reside within a cluster for normal biogenesis, although the identity and orientation of its neighbor are flexible. We use DGCR8 tethering assays and operon structure-function assays to demonstrate that local recruitment and transfer of Microprocessor enhances suboptimal substrate processing. This principle applies more broadly since genomic analysis indicates suboptimal canonical miRNAs are enriched in operons, and we validate several of these experimentally. Proximity-based enhancement of suboptimal hairpin processing provides a rationale for genomic retention of certain miRNA operons and may explain preferential evolutionary emergence of miRNA operons. Shang et al. investigate the biogenesis of clustered miRNAs, which were largely considered to be processed independently. They document multiple mammalian miRNA operons bearing suboptimal substrates of the Drosha/DGCR8 (Microprocessor) complex, which require close proximity to canonical miRNA neighbors to recruit and locally transfer Microprocessor for their optimal nuclear biogenesis. © 2020 Elsevier Inc.
Keywords: controlled study; unclassified drug; nonhuman; protein motif; microrna; gene locus; gene frequency; genome-wide association study; molecular evolution; base pairing; dna flanking region; rna processing; biogenesis; ribonuclease iii; northern blotting; operon; rna analysis; mir-451; microrna 451; drosha; microprocessor; human; article; crispr-cas9 system; dgcr8; k-562 cell line; mirna cluster
Journal Title: Molecular Cell
Volume: 78
Issue: 2
ISSN: 1097-2765
Publisher: Cell Press  
Date Published: 2020-04-16
Start Page: 303
End Page: 316.e4
Language: English
DOI: 10.1016/j.molcel.2020.02.009
PROVIDER: scopus
PUBMED: 32302542
Notes: Article -- Export Date: 1 May 2020 -- Source: Scopus
Citation Impact
MSK Authors
  1. Eric C Lai
    123 Lai
  2. Renfu Shang
    1 Shang