Environmental control of the in vivo oligomerization of nucleoid protein H-NS.
J Mol Biol
; 355(2): 169-74, 2006 Jan 13.
Article
in En
| MEDLINE
| ID: mdl-16303134
ABSTRACT
The nucleoid-associated transcriptional repressor H-NS forms both dimers and tetramers in vivo. Two types of two-hybrid systems, one capable of detecting protein dimerization and the other protein tetramerization, have been used to determine whether environmental changes could affect the oligomerization capacity of this protein in the cell. Increasing the temperature from 37 degrees C to 48 degrees C and changing the pH between 4.0 and 9.0 did not influence either dimerization or tetramerization, whereas lowering the temperature below 25 degrees C and increasing osmolarity were found to reduce the formation of H-NS tetramers, which are the active form of this protein, without affecting dimerization. These findings provide a rationale to explain the induction of H-NS expression during cold-shock, suggest a mechanism contributing to derepressing osmotic-shock genes transcriptionally regulated by H-NS and indicate that changes of the oligomerization properties of H-NS do not play a role in the H-NS and temperature-dependent control of virulence gene expression.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
Repressor Proteins
/
Bacterial Proteins
/
Escherichia coli Proteins
/
DNA-Binding Proteins
/
Escherichia coli
Language:
En
Journal:
J Mol Biol
Year:
2006
Document type:
Article
Affiliation country:
Italy
Publication country:
HOLANDA
/
HOLLAND
/
NETHERLANDS
/
NL
/
PAISES BAJOS
/
THE NETHERLANDS