Diel Expression of Cell Cycle-Related Genes in Synchronized Cultures of Prochlorococcus sp. Strain PCC 9511
AUTOR(ES)
Holtzendorff, J.
FONTE
American Society for Microbiology
RESUMO
The cell cycle of the chlorophyll b-possessing marine cyanobacterium Prochlorococcus is highly synchronized under natural conditions. To understand the underlying molecular mechanisms we cloned and sequenced dnaA and ftsZ, two key cell cycle-associated genes, and studied their expression. An axenic culture of Prochlorococcus sp. strain PCC 9511 was grown in a turbidostat with a 12 h–12 h light-dark cycle for 2 weeks. During the light periods, a dynamic light regimen was used in order to simulate the natural conditions found in the upper layers of the world's oceans. This treatment resulted in strong cell cycle synchronization that was monitored by flow cytometry. The steady-state mRNA levels of dnaA and ftsZ were monitored at 4-h intervals during four consecutive division cycles. Both genes exhibited clear diel expression patterns with mRNA maxima during the replication (S) phase. Western blot experiments indicated that the peak of FtsZ concentration occurred at night, i.e., at the time of cell division. Thus, the transcript accumulation of genes involved in replication and division is coordinated in Prochlorococcus sp. strain PCC 9511 and might be crucial for determining the timing of DNA replication and cell division.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=94958Documentos Relacionados
- In Vivo Regulation of Glutamine Synthetase Activity in the Marine Chlorophyll b-Containing Cyanobacterium Prochlorococcus sp. Strain PCC 9511 (Oxyphotobacteria)†
- Identification of a cell cycle-related gene, cyclin, in Nicotiana tabacum (L.).
- Cell Cycle-related and Endogenously Controlled Circadian Photosynthetic Rhythms in Euglena1
- Cell cycle-related shifts in subcellular localization of BCR: association with mitotic chromosomes and with heterochromatin.
- Relationship between DNA cycle and growth rate in Synechococcus sp. strain PCC 6301.