TY - JOUR
T1 - Environmental control of the in vivo oligomerization of nucleoid protein H-NS
AU - Stella, Stefano
AU - Falconi, Maurizio
AU - Lammi, Matilde
AU - Gualerzi, Claudio O.
AU - Pon, Cynthia L.
PY - 2006/1/13
Y1 - 2006/1/13
N2 - 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°C to 48°C and changing the pH between 4.0 and 9.0 did not influence either dimerization or tetramerization, whereas lowering the temperature below 25°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.
AB - 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°C to 48°C and changing the pH between 4.0 and 9.0 did not influence either dimerization or tetramerization, whereas lowering the temperature below 25°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.
KW - Environmental control
KW - Protein dimerization and tetramerization
KW - Transcriptional repression
KW - Two-hybrid system
UR - http://www.scopus.com/inward/record.url?scp=28844491363&partnerID=8YFLogxK
U2 - 10.1016/j.jmb.2005.10.034
DO - 10.1016/j.jmb.2005.10.034
M3 - Journal article
C2 - 16303134
AN - SCOPUS:28844491363
SN - 0022-2836
VL - 355
SP - 169
EP - 174
JO - Journal of Molecular Biology
JF - Journal of Molecular Biology
IS - 2
ER -