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Consequences of a deletion in dspA on transcript accumulation in Synechocystis sp. strain PCC6803.

ABSTRACT: Abstract: A sensor histidine kinase of Synechococcus sp. strain PCC7942, designated nblS, was previously identified and shown to be critical for the acclimation of cells to high-light and nutrient limitation conditions and to influence the expression of a number of light-responsive genes. The nblS orthologue in Synechocystis sp. strain PCC6803 is designated dspA (also called hik33). We have generated a dspA null mutant and analyzed global gene expression in both the mutant and wild-type strains under high- and low-light conditions. The mutant is aberrant for the expression of many genes encoding proteins critical for photosynthesis, phosphate and carbon acquisition, and the amelioration of stress conditions. Furthermore, transcripts from a number of genes normally detected only during exposure of wild-type cells to high-light conditions become partially constitutive in the low-light-grown dspA mutant. Other genes for which transcripts decline upon exposure of wild-type cells to high light are already lower in the mutant during growth in low light. These results suggest that DspA may influence gene expression in both a positive and a negative manner and that the dspA mutant behaves as if it were experiencing stress conditions (e.g., high-light exposure) even when maintained at near-optimal growth conditions for wild-type cells. This is discussed with respect to the importance of DspA for regulating the responses of the cell to environmental cues. A strain or line experiment design type assays differences between multiple strains, cultivars, serovars, isolates, lines from organisms of a single species. User Defined

ORGANISM(S): Synechocystis sp. PCC 6803

SUBMITTER: Chao-Jung Tu

PROVIDER: E-GEOD-4019 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

Consequences of a deletion in dspA on transcript accumulation in Synechocystis sp. strain PCC6803.

Tu Chao-Jung CJ Shrager Jeffrey J Burnap Robert L RL Postier Bradley L BL Grossman Arthur R AR

Journal of bacteriology 20040601 12

A sensor histidine kinase of Synechococcus sp. strain PCC7942, designated nblS, was previously identified and shown to be critical for the acclimation of cells to high-light and nutrient limitation conditions and to influence the expression of a number of light-responsive genes. The nblS orthologue in Synechocystis sp. strain PCC6803 is designated dspA (also called hik33). We have generated a dspA null mutant and analyzed global gene expression in both the mutant and wild-type strains under high ...[more]

PMID: 15175303

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Dataset Information

Consequences of a deletion in dspA on transcript accumulation in Synechocystis sp. strain PCC6803.

Publications

Consequences of a deletion in dspA on transcript accumulation in Synechocystis sp. strain PCC6803.

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