Ser-Gln sites of SOG1 are rapidly hyperphosphorylated in response to DNA double-strand breaks

Plant Signal Behav. 2018;13(6):e1477904. doi: 10.1080/15592324.2018.1477904. Epub 2018 Jun 25.

Abstract

The DNA damage response system (DDR) is crucial in addressing DNA double-strand breaks (DSBs), which pose a severe threat to genomic integrity. The SOG1 transcription factor is a master regulator of the Arabidopsis thaliana DDR. We previously showed that hyperphosphorylation of five Ser-Gln sites of SOG1 is the molecular switch to activate the DDR. In this study, we determined that SOG1 is hyperphosphorylated within 20 minutes following DSB-inducing treatment, followed by activation of several SOG1 target genes. Using SOG1 phosphorylation mutants, we demonstrated that although the hyperphosphorylation sites remain unchanged over time, the amount of hyperphosphorylation gradually increases. These observations suggest that rapid SOG1 hyperphosphorylation is limited by the amount of active kinases.

Abbreviations: SOG1, suppressor of gamma response; ATM, Ataxia telangiectasia mutated; ATR, ATM and Rad3-related.

Keywords: A. thaliana; DNA damage response; SOG1; hyperphosphorylation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / genetics
  • Arabidopsis / metabolism*
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism*
  • DNA Breaks, Double-Stranded*
  • Gene Expression Regulation, Plant / genetics
  • Phosphorylation
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*

Substances

  • Arabidopsis Proteins
  • Transcription Factors

Grants and funding

This work was supported by JSPS KAKENHI (13J40017 and 17K07455 to K.O.Y., 16H01472, 16K07408, 18H04787 and 18H04844 to S. K.) and by the MEXT Supported Program for the Strategic Research Foundation at Private Universities from the Ministry of Education, Culture, Sports, Science & Technology of Japan, Grant Number S1511023 to S.K.