Plant and Cell Physiology, 1997, Vol. 38, No. 3 319-326
© 1997
Regulation of Synthesis of PSI in the Cyanophytes Synechocystis PCC6714 and Plectonema boryanum during the Acclimation of the Photosystem Stoichiometry to the Light Quality
Department of Cell Biology, National Institute for Basic Biology Okazaki, Aichi, 444 Japan
The effects of light quality on the formation of the PSI complex were examined in Synechocystis PCC6714 and in Plectonema boryanum. The rate of increase in levels of core polypeptides of PSI, PsaA/B, doubled upon shift from Chl a-absorbed light (PSI light) to phycobilisome-ab-sorbed light (PSII light). The elevated rate was decreased upon the reverse shift. Half time of the acceleration was approximately 10 min, and that of the decrease was approximately 4 min. The rate of degradation of the polypeptides was far lower than the rate of the increase under either light regime. Neither synthesis nor degradation of the PsbA and PsbC polypeptides of PSII was significantly altered by the light quality. We conclude that synthesis of the PSI complex is chromatically regulated to allow adjustments in photosystem stoichiometry. The level of mRNA for PsaA/B was not altered by the light regime. Anomalous inhibition by chloramphenicol suggested that the regulation occurs at a step(s) other than the peptide elongation step, perhaps at the initiation of the ribosome cycle or at the insertion of Chl a for the stabilization of the polypeptides. The pho-toreduction of protochlorophyllide (Pchlide) was compared with the synthesis of the polypeptides in a mutant of Plectonema boryanum that lacked Pchlide dark reductase (YFC1004). The results indicated that the synthesis of stable PsaA/B polypeptides was not limited by the reduction of Pchlide, although the synthesis did depend on a supply of Chl a.
1Present address: Department of Plant Biology, University of Maryland at College Park, MD 20742, U.S.A.
2Present address: Department of Marine Bioscience, Fukui Pre-fectural University, Obama, Fukui, 917 Japan
(Received August 26, 1996; Accepted December 26, 1996)
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  R. M. Morgan-Kiss, J. C. Priscu, T. Pocock, L. Gudynaite-Savitch, and N. P. A. Huner Adaptation and Acclimation of Photosynthetic Microorganisms to Permanently Cold Environments Microbiol. Mol. Biol. Rev., March 1, 2006; 70(1): 222 - 252. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Herranen, T. Tyystjarvi, and E.-M. Aro Regulation of Photosystem I Reaction Center Genes in Synechocystis sp. Strain PCC 6803 during Light Acclimation Plant Cell Physiol., September 1, 2005; 46(9): 1484 - 1493. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Matsuo and J. Obokata Dual Roles of Photosynthetic Electron Transport in Photosystem I Biogenesis: Light Induction of mRNAs and Chromatic Regulation at Post-mRNA Level Plant Cell Physiol., October 15, 2002; 43(10): 1189 - 1197. [Abstract] [Full Text] [PDF]
|
|