Characterization of Blue Light Signal Transduction Chains That Control Development and Maintenance of Sexual Competence in Chlamydomonas reinhardtii.

AUTOR(ES)

Pan, J. M.

RESUMO

Blue light induces the differentiation of Chlamydomonas reinhardtii pregametes to gametes. The light-induced conversion of pregametes to gametes is protein synthesis dependent and proceeds only after a lag phase. Upon incubation in the dark, gametes lost their mating ability, resulting in dark-inactivated gametes. Reillumination rapidly restored mating competence and this was shown to be independent of protein synthesis. Apparently, differentiation and maintenance of gametic competence are both regulated by light. Whether one or two light-activated signal pathways are involved was investigated using pharmacological compounds that affect signal transduction. Compounds that affected pregamete-to-gamete conversion affected the expression of a gamete-specific gene in a similar fashion. Other drugs affected only dark-inactivated gametes, suggesting that reactivating gametes requires a separate signaling pathway. Combined treatments provided evidence for the consecutive action of a phosphatase and a protein kinase C-like kinase in the light-induced reactivation process.

Documentos Relacionados

• Dissection of the Blue-Light-Dependent Signal-Transduction Pathway Involved in Gametic Differentiation of Chlamydomonas reinhardtii.
• Blue-Light-Regulated Expression of Genes for Two Early Steps of Chlorophyll Biosynthesis in Chlamydomonas reinhardtii.
• Genes Involved in Light Control of Sexual Differentiation in Chlamydomonas Reinhardtii
• Isolation and characterization of glutamine synthetase genes in Chlamydomonas reinhardtii.
• Three light-inducible heat shock genes of Chlamydomonas reinhardtii.