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Plant Physiol. 1996 Sep;112(1):303-309. doi: 10.1104/pp.112.1.303.

Dissection of the Blue-Light-Dependent Signal-Transduction Pathway Involved in Gametic Differentiation of Chlamydomonas reinhardtii.

Plant physiology

J. M. Pan, M. A. Haring, C. F. Beck

Affiliations

  1. University of Freiburg, Institute for Biology III, Schaenzlestrasse 1, D-79104 Freiburg, Germany (J.-M.P., C.F.B.).

PMID: 12226393 PMCID: PMC157950 DOI: 10.1104/pp.112.1.303

Abstract

Gametogenesis of the green alga Chlamydomonas reinhardtii may be viewed as a two-step process that is controlled by the environmental cues of nitrogen deprivation and blue light. Initiation of gametogenesis is induced by nitrogen deprivation, resulting in mating-incompetent pregametes, when cells are kept in the dark. For the completion of gametic differentiation light is required. Pregametes were treated with pharmacological compounds to influence the light-dependent conversion to mature gametes. Dibutyryl-cyclic 3[prime]5[prime] adenosinemonophosphate, papaverine, and genistein were found to inhibit the progression of gametogenesis in the light. Treatment of pregametes in the dark with either staurosporine or papaverine resulted in their conversion to mature gametes. Apparently, papaverine has different effects in the dark and in the light; the effect of staurosporine suggested that a protein kinase C-like component inhibits the conversion of pregametes to gametes, a block that normally is relieved by illumination. This hypothesis was corroborated by the observation that activators of protein kinase C, N-heptyl-5-chloro-1-naphthalenesulfonamide, N- (6-phenylhexyl)-5-chloro-1-naphthalenesulfonamide, and the phorbolester phorbol-12-myristate 13-acetate inhibited gametogenesis in the light. Genistein and dibutyryl-cyclic 3[prime]5[prime] adenosinemonophosphate were able to inhibit the dark activation caused by staurosporine treatment, suggesting that their targets work downstream from the "protein kinase C-like" kinase. Surprisingly, staurosporine and papaverine worked synergystically on the activation of pregametes in the dark.

References

  1. Plant Mol Biol. 1994 Dec;26(5):1271-87 - PubMed
  2. Plant Cell. 1994 Nov;6(11):1529-41 - PubMed
  3. EMBO J. 1993 Sep;12 (9):3497-505 - PubMed
  4. J Biol Chem. 1994 May 20;269(20):14329-32 - PubMed
  5. Proc Natl Acad Sci U S A. 1993 Aug 1;90(15):6981-5 - PubMed
  6. Cell. 1994 Apr 8;77(1):73-81 - PubMed
  7. J Cell Biol. 1987 Nov;105(5):2279-92 - PubMed
  8. Proc Natl Acad Sci U S A. 1994 Feb 1;91(3):952-6 - PubMed
  9. Mol Gen Genet. 1993 Nov;241(3-4):415-21 - PubMed
  10. J Gen Physiol. 1954 Jul 20;37(6):729-42 - PubMed
  11. Trends Neurosci. 1989 Nov;12 (11):425-32 - PubMed
  12. Plant Physiol. 1992 Mar;98(3):822-6 - PubMed
  13. J Biol Chem. 1982 Apr 25;257(8):4593-602 - PubMed
  14. Br J Pharmacol. 1993 Sep;110(1):369-77 - PubMed
  15. Cell. 1993 Jun 4;73(5):937-52 - PubMed
  16. Plant Physiol. 1991 Sep;97(1):118-21 - PubMed

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