Document Detail


Integration of light signals by the retinoblastoma pathway in the control of S phase entry in the picophytoplanktonic cell Ostreococcus.
MedLine Citation:
PMID:  20502677     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Although the decision to proceed through cell division depends largely on the metabolic status or the size of the cell, the timing of cell division is often set by internal clocks such as the circadian clock. Light is a major cue for circadian clock entrainment, and for photosynthetic organisms it is also the main source of energy supporting cell growth prior to cell division. Little is known about how light signals are integrated in the control of S phase entry. Here, we present an integrated study of light-dependent regulation of cell division in the marine green alga Ostreococcus. During early G1, the main genes of cell division were transcribed independently of the amount of light, and the timing of S phase did not occur prior to 6 hours after dawn. In contrast S phase commitment and the translation of a G1 A-type cyclin were dependent on the amount of light in a cAMP-dependent manner. CyclinA was shown to interact with the Retinoblastoma (Rb) protein during S phase. Down-regulating Rb bypassed the requirement for CyclinA and cAMP without altering the timing of S phase. Overexpression of CyclinA overrode the cAMP-dependent control of S phase entry and led to early cell division. Therefore, the Rb pathway appears to integrate light signals in the control of S phase entry in Ostreococcus, though differential transcriptional and posttranscriptional regulations of a G1 A-type cyclin. Furthermore, commitment to S phase depends on a cAMP pathway, which regulates the synthesis of CyclinA. We discuss the relative involvements of the metabolic and time/clock signals in the photoperiodic control of cell division.
Authors:
Mickael Moulager; Florence Corellou; Valérie Vergé; Marie-Line Escande; François-Yves Bouget
Related Documents :
11718577 - Enzyme-cytochemically detectable glucose-6-phosphate dehydrogenase in human villous mac...
6835397 - Caulobacter flagellin mrna segregates asymmetrically at cell division.
15556027 - Cytoskeletal elements in bacteria.
9725857 - Arabidopsis tso1 regulates directional processes in cells during floral organogenesis.
16317137 - Fisetin inhibits the activities of cyclin-dependent kinases leading to cell cycle arres...
12746977 - Nuclear morphometric features of epithelial cells lining keratocysts.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2010-05-20
Journal Detail:
Title:  PLoS genetics     Volume:  6     ISSN:  1553-7404     ISO Abbreviation:  PLoS Genet.     Publication Date:  2010 May 
Date Detail:
Created Date:  2010-05-26     Completed Date:  2010-09-13     Revised Date:  2013-05-29    
Medline Journal Info:
Nlm Unique ID:  101239074     Medline TA:  PLoS Genet     Country:  United States    
Other Details:
Languages:  eng     Pagination:  e1000957     Citation Subset:  IM    
Affiliation:
Université Pierre et Marie Curie, Paris 06, France.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Light*
Plankton / cytology,  metabolism,  radiation effects*
Retinoblastoma Protein / metabolism*
S Phase / radiation effects*
Chemical
Reg. No./Substance:
0/Retinoblastoma Protein
Comments/Corrections

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Mutation in archain 1, a subunit of COPI coatomer complex, causes diluted coat color and Purkinje ce...
Next Document:  The mating type locus (MAT) and sexual reproduction of Cryptococcus heveanensis: insights into the e...