The Nuclear-Retained Noncoding RNA MALAT1 Regulates Alternative Splicing by Modulating SR Splicing Factor Phosphorylation

Authors
Vidisha Tripathi, Jonathan D. Ellis, Zhen Shen,1 David Y. Song, Qun Pan, Andrew T. Watt, Susan M. Freier, C. Frank Bennett, Alok Sharma, Paula A. Bubulya, Benjamin J. Blencowe, Supriya G. Prasanth, and Kannanganattu V. Prasanth
11-08-2010
12:00pm
PST
Categories
Long Noncoding RNAs & Circular RNAs
Speaker
Ian Vaughn
Abstract
Alternative splicing (AS) of pre-mRNA is utilized by higher eukaryotes to achieve increased transcriptome and proteomic complexity. The serine/arginine (SR) splicing factors regulate tissue- or cell-typespecific AS in a concentration- and phosphorylation-dependent manner. However, the mechanisms that modulate the cellular levels of active SR proteins remain to be elucidated. In the present study, we provide evidence for a role for the long nuclearretained regulatory RNA (nrRNA), MALAT1 in AS regulation. MALAT1 interacts with SR proteins and influences the distribution of these and other splicing factors in nuclear speckle domains. Depletion of MALAT1 or overexpression of an SR protein changes the AS of a similar set of endogenous pre-mRNAs. Furthermore, MALAT1 regulates cellular levels of phosphorylated forms of SR proteins. Taken together, our results suggest that MALAT1 regulates AS by modulating the levels of active SR proteins. Our results further highlight the role for an nrRNA in the regulation of gene expression.