Abstract
Because of their sessile nature, plants have adopted varied strategies for growing and reproducing in an ever-changing environment. Control of mRNA levels and pre-mRNA alternative splicing are key regulatory layers that contribute to adjust and synchronize plant growth and development with environmental changes. Transcription and alternative splicing are thought to be tightly linked and coordinated, at least in part, through a network of transcriptional and splicing regulatory factors that interact with the carboxyl-terminal domain (CTD) of the largest subunit of RNA polymerase II. One of the proteins that has been shown to play such a role in yeast and mammals is pre-mRNA-PROCESSING PROTEIN 40 (PRP40, also known as CA150, or TCERG1). In plants, members of the PRP40 family have been identified and shown to interact with the CTD of RNA Pol II, but their biological functions remain unknown. Here, we studied the role of AtPRP40C, in Arabidopsis thaliana growth, development and stress tolerance, as well as its impact on the global regulation of gene expression programs. We found that the prp40c knockout mutants display a late-flowering phenotype under long day conditions, associated with minor alterations in red light signaling. An RNA-seq based transcriptome analysis revealed differentially expressed genes related to biotic stress responses and also differentially expressed as well as differentially spliced genes associated with abiotic stress responses. Indeed, the characterization of stress responses in prp40c mutants revealed an increased sensitivity to salt stress and an enhanced tolerance to Pseudomonas syringae pv. maculicola (Psm) infections. This constitutes the most thorough analysis of the transcriptome of a prp40 mutant in any organism, as well as the first characterization of the molecular and physiological roles of a member of the PRP40 protein family in plants. Our results suggest that PRP40C is an important factor linking the regulation of gene expression programs to the modulation of plant growth, development, and stress responses.
Highlights
Plants are permanently subjected to environmental changes that adversely affect their growth and development either in natural or agricultural settings
We initially performed a phylogenetic analysis of the pre-mRNA processing protein 40 family (PRP40) (Figure 1A)
We found that PROCESSING PROTEIN 40 (PRP40) from both human and Arabidopsis genomes cluster in two separate clades, one that includes the so-called PRP40A and B types and another that includes HsTCERG1/CA150 and AtPRP40C
Summary
Plants are permanently subjected to environmental changes that adversely affect their growth and development either in natural or agricultural settings. Synthesis of mRNA by the RNA polymerase II (RNA Pol II) is coordinated with subsequent RNA processing events such as 5’ capping, splicing, cleavage, and polyadenylation (Darnell, 2013). The largest subunit of the RNA Pol II couples transcription and pre-mRNA processing via its C-terminal domain (CTD). The CTD comprises tandem Tyr1–Ser2–Pro3–Thr4–Ser5–Pro6–Ser heptapeptide repeats that are highly conserved in eukaryotes (Allison et al, 1988; Nawrath et al, 1990) and interacts with capping, splicing, and polyadenylation factors, acting as a scaffolding platform for mRNA processing factors (Greenleaf, 1993; McCracken et al, 1997; Misteli and Spector, 1999; Buratowski, 2003; Phatnani and Greenleaf, 2006; Muñoz et al, 2010; Braunschweig et al, 2013). The splicing reaction begins with the initial recognition of the 5’ and 3’ splice sites (5’SS and 3’SS, respectively) at the exon–intron boundaries, the branch point sequence (BPS), and the polypyrimidine tract (Py) (Wahl et al, 2009; Meyer et al, 2015); the completion of the splicing process involves the removal of an intron and the ligation of the resulting exons
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
