Open AccessGW182 Proteins Restrict Extracellular Vesicle-Mediated Export of MicroRNAs in Mammalian Cancer Cells
Author(s) -
Souvik Ghosh,
Kamalika Mukherjee,
Yogaditya Chakrabarty,
Susanta Chatterjee,
Bartika Ghoshal,
S. N. Bhattacharyya
Publication year - 2021
Publication title -
molecular and cellular biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.14
H-Index - 327
eISSN - 1067-8824
pISSN - 0270-7306
DOI - 10.1128/mcb.00483-20
Subject(s) - biology , microrna , extracellular vesicle , microbiology and biotechnology , cancer cell , p bodies , gene silencing , rna interference , rna , argonaute , messenger rna , cancer , genetics , gene , microvesicles , translation (biology)
MicroRNAs (miRNAs) are small regulatory RNAs of relatively long half-life in non-proliferative human cells. However, in cancer cells the half-lives of miRNAs are comparatively short. To understand the mechanism of rapid miRNA turnover in cancer cells, we explored the effect of target mRNAs on the abundance of the miRNAs that repress them. We have noted an accelerated extracellular vesicle (EV)-mediated export of miRNAs in presence of their target mRNAs in mammalian cells, and this target-driven miRNA-export process is retarded by Ago2-interacting protein GW182B. The GW182 group of proteins are localized to GW182 bodies or RNA processing bodies in mammalian cells, and GW182B-dependent retardation of miRNA export depends on GW body integrity and is independent of the HuR protein-mediated auxiliary pathway of miRNA export. Our data thus support the existence of a HuR-independent pathway of miRNA export in human cells that can be targeted in MDA-MB-231 cancer cells, to increase the level of cellular let-7a, a known negative regulator of cancer growth.