Identification and Regulation of Tomato Serine/Arginine-Rich Proteins Under High Temperatures

Remus R E Rosenkranz; Samia Bachiri; Stavros Vraggalas; Mario Keller; Stefan Simm; Enrico Schleiff; Sotirios Fragkostefanakis

doi:10.3389/fpls.2021.645689

Identification and Regulation of Tomato Serine/Arginine-Rich Proteins Under High Temperatures

Front Plant Sci. 2021 Mar 29:12:645689. doi: 10.3389/fpls.2021.645689. eCollection 2021.

Authors

Remus R E Rosenkranz¹, Samia Bachiri¹, Stavros Vraggalas¹, Mario Keller^{1

2}, Stefan Simm³, Enrico Schleiff^{1

2

4}, Sotirios Fragkostefanakis¹

Affiliations

¹ Department of Biosciences, Molecular Cell Biology of Plants, Goethe University, Frankfurt am Main, Germany.
² Buchmann Institute for Molecular Life Sciences, Goethe University, Frankfurt am Main, Germany.
³ Institute of Bioinformatics, University Medicine Greifswald, Greifswald, Germany.
⁴ Frankfurt Institute of Advanced Studies, Frankfurt am Main, Germany.

Abstract

Alternative splicing is an important mechanism for the regulation of gene expression in eukaryotes during development, cell differentiation or stress response. Alterations in the splicing profiles of genes under high temperatures that cause heat stress (HS) can impact the maintenance of cellular homeostasis and thermotolerance. Consequently, information on factors involved in HS-sensitive alternative splicing is required to formulate the principles of HS response. Serine/arginine-rich (SR) proteins have a central role in alternative splicing. We aimed for the identification and characterization of SR-coding genes in tomato (Solanum lycopersicum), a plant extensively used in HS studies. We identified 17 canonical SR and two SR-like genes. Several SR-coding genes show differential expression and altered splicing profiles in different organs as well as in response to HS. The transcriptional induction of five SR and one SR-like genes is partially dependent on the master regulator of HS response, HS transcription factor HsfA1a. Cis-elements in the promoters of these SR genes were predicted, which can be putatively recognized by HS-induced transcription factors. Further, transiently expressed SRs show reduced or steady-state protein levels in response to HS. Thus, the levels of SRs under HS are regulated by changes in transcription, alternative splicing and protein stability. We propose that the accumulation or reduction of SRs under HS can impact temperature-sensitive alternative splicing.

Keywords: Solanum lycopersicum; alternative splicing; heat stress; pre-mRNA; regulation.