HOMEPRODUCTSCOMPANYCONTACTFAQResearchDictionaryPharmaSign Up FREE or Login

The histidine kinase Hik34 is involved in thermotolerance by regulating the expression of heat shock genes in synechocystis.

Abstract
Histidine kinases (Hiks) in Synechocystis sp. PCC 6803 are involved in the transduction of signals associated with various kinds of environmental stress. To examine the potential role in thermotolerance of Hiks, we used genome microarray analysis to screen a Hik knockout library for mutations that affected the expression of genes for heat shock proteins. Mutation of the hik34 gene enhanced the levels of transcripts of a number of heat shock genes, including htpG and groESL1. Overexpression of the hik34 gene repressed the expression of these heat shock genes. In addition, the cells with a mutant gene for Hik34 (DeltaHik34 cells) survived incubation at 48 degrees C for 3 h, while wild-type cells and cells with mutations in other Hiks were killed. However, mutation of the hik34 gene had only an insignificant effect on the global expression of genes upon incubation of the mutant cells at 44 degrees C for 20 min. Quantitative two-dimensional gel electrophoresis revealed that levels of GroES and HspA were elevated in DeltaHik34 cells after incubation of cells at 42 degrees C for 60 min. We overexpressed recombinant Hik34 protein in Escherichia coli and purified it. We found that the protein was autophosphorylated in vitro at physiological temperatures, but not at elevated temperatures, such as 44 degrees C. These results suggest that Hik34 might negatively regulate the expression of certain heat shock genes that might be related to thermotolerance in Synechocystis.
AuthorsIwane Suzuki, Yu Kanesaki, Hidenori Hayashi, John J Hall, William J Simon, Antoni R Slabas, Norio Murata
JournalPlant physiology (Plant Physiol) Vol. 138 Issue 3 Pg. 1409-21 (Jul 2005) ISSN: 0032-0889 [Print] United States
PMID15965020 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
Chemical References
  • Bacterial Proteins
  • DNA Primers
  • Heat-Shock Proteins
  • Protein Kinases
  • Histidine Kinase
Topics
  • Bacterial Proteins (genetics)
  • Base Sequence
  • Cyanobacteria (enzymology)
  • DNA Primers
  • Electrophoresis, Gel, Two-Dimensional
  • Gene Deletion
  • Gene Expression Regulation, Bacterial
  • Gene Expression Regulation, Enzymologic
  • Gene Library
  • Genetic Vectors
  • Heat-Shock Proteins (genetics)
  • Histidine Kinase
  • Homeostasis
  • Mutagenesis
  • Oligonucleotide Array Sequence Analysis
  • Phosphorylation
  • Protein Kinases (metabolism)
  • Species Specificity
  • Synechocystis (enzymology, genetics)
  • Temperature

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research graph!


Choose Username:
Email:
Password:
Verify Password:
Enter Code Shown: