Photosynthesis Research

, Volume 18, Issue 1, pp 99–132

Photoregulation of gene expression in the filamentous cyanobacterium Calothrix sp. PCC 7601: light-harvesting complexes and cell differentiation

  • Nicole Tandeau De Marsac
  • Didier Mazel
  • Thierry Damerval
  • Gérard Guglielmi
  • Veronique Capuano
  • Jean Houmard
Light-harvesting Minireview

DOI: 10.1007/BF00042981

Cite this article as:
De Marsac, N.T., Mazel, D., Damerval, T. et al. Photosynth Res (1988) 18: 99. doi:10.1007/BF00042981

Abstract

Light plays a major role in many physiological processes in cyanobacteria. In Calothrix sp. PCC 7601, these include the biosynthesis of the components of the light-harvesting antenna (phycobilisomes) and the differentiation of the vegetative trichomes into hormogonia (short chains of smaller cells). In order to study the molecular basis for the photoregulation of gene expression, physiological studies have been coupled with the characterization of genes involved either in the formation of phycobilisomes or in the synthesis of gas vesicles, which are only present at the hormogonial stage.

In each system, a number of genes have been isolated and sequenced. This demonstrated the existence of multigene families, as well as of gene products which have not yet been identified biochemically. Further studies have also established the occurrence of both transcriptional and post-transcriptional regulation. The transcription of genes encoding components of the phycobilisome rods is light-wavelength dependent, while translation of the phycocyanin genes may require the synthesis of another gene product irrespective of the light regime. In this report, we propose two hypothetical models which might be part of the complex regulatory mechanisms involved in the formation of functional phycobilisomes. On the other hand, transcription of genes involved in the gas vesicles formation (gvp genes) is turned on during hormogonia differentiation, while that of phycobiliprotein genes is simultaneously turned off. In addition, and antisense RNA which might modulate the translation of the gvp mRNAs is synthezised.

Key words

Calothrix sp. PCC 7601 gas vesicles hormogonia photoregulation phycobiliproteins phycobilisomes 

Abbreviations

AP

allophycocyanin

APB

allophycocyanin B

bp

base pair

GVP

gas vesicle protein

kb

kilobase

kDa

kilodalton

L

linker polypeptide

PC

phycocyanin

PCC

Pasteur Culture Collection

PE

phycoerythrin

UTEX

University of Texas algal collection

Copyright information

© Kluwer Academic Publishers 1988

Authors and Affiliations

  • Nicole Tandeau De Marsac
    • 1
  • Didier Mazel
    • 1
  • Thierry Damerval
    • 1
  • Gérard Guglielmi
    • 1
  • Veronique Capuano
    • 1
  • Jean Houmard
    • 1
  1. 1.Unité de Physiologie Microbienne (C.N.R.S., U.A. 1129), Département de Biochimie et Génétique MoléculaireInstitut PasteurParis Cedex 15France