Expression analysis of microbial rhodopsin-like genes in Guillardia theta

PLoS One. 2020 Dec 3;15(12):e0243387. doi: 10.1371/journal.pone.0243387. eCollection 2020.

Abstract

The Cryptomonad Guillardia theta has 42 genes encoding microbial rhodopsin-like proteins in their genomes. Light-driven ion-pump activity has been reported for some rhodopsins based on heterologous E. coli or mammalian cell expression systems. However, neither their physiological roles nor the expression of those genes in native cells are known. To reveal their physiological roles, we investigated the expression patterns of these genes under various growth conditions. Nitrogen (N) deficiency induced color change in exponentially growing G. theta cells from brown to green. The 29 rhodopsin-like genes were expressed in native cells. We found that the expression of 6 genes was induced under N depletion, while that of another 6 genes was reduced under N depletion.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Color
  • Cryptophyta / genetics*
  • Cryptophyta / growth & development
  • Cryptophyta / metabolism
  • Gene Expression Profiling
  • Nitrogen / metabolism
  • Phylogeny
  • Rhodopsins, Microbial / genetics*
  • Rhodopsins, Microbial / metabolism

Substances

  • Rhodopsins, Microbial
  • Nitrogen

Grants and funding

This work was supported by the Japan Society for the Promotion of Science (JSPS) Grant-in-Aid for Scientific Research (KAKENHI), Japan (grant numbers 17H04694 to K.I. and 25104009 and 15H02391 to H.K.). There was no additional external funding received for this study. The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.