The circadian rhythm regulator RpaA modulates photosynthetic electron transport and alters the preferable temperature range for growth in a cyanobacterium

FEBS Lett. 2021 May;595(10):1480-1492. doi: 10.1002/1873-3468.14075. Epub 2021 Mar 31.

Abstract

Cyanobacterial strains can grow within a specific temperature range that approximately corresponds to their natural habitat. However, how the preferable temperature range for growth (PTRG) is determined at the molecular level remains unclear. In this study, we detected a PTRG upshift in a mutant strain of Synechococcus elongatus PCC 7942 lacking the circadian rhythm regulator RpaA. Subsequent analyses revealed that RpaA decreases the electron transport from photosystem I to NADPH. The change in electron transport likely inhibits H2 O2 generation under high-temperature conditions and contributes to the observed PTRG upshift in rpaA-deficient cells. The importance of the effects of the circadian rhythm regulator on the PTRG is discussed.

Keywords: RpaA; circadian clock; cyanobacteria; photosynthesis; preferable temperature range for growth.

Publication types

  • Research Support, Non-U.S. Gov't
  • Retracted Publication

MeSH terms

  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Circadian Rhythm*
  • Electron Transport
  • Gene Deletion
  • Hydrogen Peroxide / metabolism
  • NADP / metabolism
  • Photosynthesis*
  • Photosystem I Protein Complex / metabolism
  • Synechococcus / genetics
  • Synechococcus / growth & development*
  • Synechococcus / metabolism*
  • Temperature*
  • Time Factors

Substances

  • Bacterial Proteins
  • Photosystem I Protein Complex
  • NADP
  • Hydrogen Peroxide

Supplementary concepts

  • Synechococcus elongatus