Postranslational Modifications Affecting Post-transcriptional Mechanisms Controlling Plant Development

TORCHIO, JEANETTE; STAIGER, DOROTHEE; SCHUSTER, CLAUDIO; YANOVSKY, MARCELO; PEREZ-SANTANGELO, SOLEDAD; TINO KÖSTER; MATEOS, J. L.

Nara

Congreso; Postranscriptional Gene REgulation in Plants; 2019

Post-transcriptional mechanisms are largely involved in plant development. Among them, pre-mRNA splicing is catalyzed by the spliceosome, a complex molecular machinery composed of small U-rich RNAs (U-snRNAs), Sm or LSm (in U6 snRNA) proteins, and several snRNP specific proteins. Sm proteins are modified by arginine (R) simmetric dimethylation (sDMA) deposited by PROTEIN ARGININE METHYLTRANSFERASES (PRMTs). The ability of methyl-Rs to act as glue attracting protein partners is possible through the Tudor protein family, that ?reads? the mark and are seen as molecular adaptors integrating the regulatory aspects of R methylation deposited by PRMTs. We investigated the impact of protein R methylation written by PRMT5 on the function of splicing factors in Arabidopsis. We focused on LSM4 which is methylated by PRMT5(1) and determined the impact of R methylation on LSM4 activity. Genome-wide experiments identified a subset of splicing events to be affected by this post- translational modification. Our findings reveal to which extent PRMT5 effect on splicing is mediated by methylation of splicing factors such as LSM4.