Overlapping roles of spliceosomal components SF3B1 and PHF5A in rice splicing regulation.
Haroon Butt, Jeremie Bazin, Sahar Alshareef, Ayman Eid, Moussa Benhamed, Anireddy S N Reddy, Martin Crespi, Magdy M Mahfouz
Author Information
Haroon Butt: Laboratory for Genome Engineering and Synthetic Biology, King Abdullah, University of Science and Technology (KAUST), Thuwal, Saudi Arabia. ORCID
Jeremie Bazin: CNRS, INRA, Institute of Plant Sciences Paris-Saclay IPS2, Univ Paris Sud, Univ Evry, Univ Paris-Diderot, Sorbonne Paris-Cite, Universite Paris-Saclay, Orsay, France.
Sahar Alshareef: Laboratory for Genome Engineering and Synthetic Biology, King Abdullah, University of Science and Technology (KAUST), Thuwal, Saudi Arabia. ORCID
Ayman Eid: Laboratory for Genome Engineering and Synthetic Biology, King Abdullah, University of Science and Technology (KAUST), Thuwal, Saudi Arabia. ORCID
Moussa Benhamed: CNRS, INRA, Institute of Plant Sciences Paris-Saclay IPS2, Univ Paris Sud, Univ Evry, Univ Paris-Diderot, Sorbonne Paris-Cite, Universite Paris-Saclay, Orsay, France.
Anireddy S N Reddy: Department of Biology and Program in Cell and Molecular Biology, Colorado State University, Fort Collins, CO, USA.
Martin Crespi: CNRS, INRA, Institute of Plant Sciences Paris-Saclay IPS2, Univ Paris Sud, Univ Evry, Univ Paris-Diderot, Sorbonne Paris-Cite, Universite Paris-Saclay, Orsay, France.
Magdy M Mahfouz: Laboratory for Genome Engineering and Synthetic Biology, King Abdullah, University of Science and Technology (KAUST), Thuwal, Saudi Arabia. Magdy.mahfouz@kaust.edu.sa. ORCID
The SF3B complex, a multiprotein component of the U2 snRNP of the spliceosome, plays a crucial role in recognizing branch point sequence and facilitates spliceosome assembly and activation. Several chemicals that bind SF3B1 and PHF5A subunits of the SF3B complex inhibit splicing. We recently generated a splicing inhibitor-resistant SF3B1 mutant named SF3B1 GEX1A RESISTANT 4 (SGR4) using CRISPR-mediated directed evolution, whereas splicing inhibitor-resistant mutant of PHF5A (Overexpression-PHF5A GEX1A Resistance, OGR) was generated by expressing an engineered version PHF5A-Y36C. Global analysis of splicing in wild type and these two mutants revealed the role of SF3B1 and PHF5A in splicing regulation. This analysis uncovered a set of genes whose intron retention is regulated by both proteins. Further analysis of these retained introns revealed that they are shorter, have a higher GC content, and contain shorter and weaker polypyrimidine tracts. Furthermore, splicing inhibition increased seedlings sensitivity to salt stress, consistent with emerging roles of splicing regulation in stress responses. In summary, we uncovered the functions of two members of the plant branch point recognition complex. The novel strategies described here should be broadly applicable in elucidating functions of splicing regulators, especially in studying the functions of redundant paralogs in plants.
References
J Exp Clin Cancer Res. 2018 Mar 22;37(1):65
[PMID: 29566713]
