TY - JOUR
T1 - Specific binding of a protein to a novel DNA element in the cyanobacterial small heat-shock protein gene
AU - Kojima, Kouji
AU - Nakamoto, Hitoshi
N1 - Funding Information:
This work was supported in part by a Grant-in-aid for Scientific Research (C) (no. 13640640) from the Ministry of Education, Science, Sports and Culture of Japan to H. Nakamoto. We are grateful to Dr. Nancy N. Artus for critically reading the manuscript.
PY - 2002
Y1 - 2002
N2 - Previously, it was shown that transcription of the small heat-shock protein gene, hspA, from the thermophilic cyanobacterium Synechococcus vulcanus is transiently heat-inducible at a vegetative promoter that lacks any known regulatory DNA elements. A novel regulatory mechanism that suppresses the expression of hspA under non-heat-shock condition has been postulated. In this study, it is demonstrated that a protein(s) in the extract of unstressed cells of the thermophilic cyanobacterium Thermosynechococcus elongatus, a cyanobacterium closely related to S. vulcanus, specifically binds to a 5′-untranslated region of the hspA gene. An AT-rich imperfect inverted-repeat sequence (ACAAgcAAA-TTTagTTGT) as a target for a putative DNA-binding protein has been identified. The DNA-binding activity in the cell as well as in the cell extract was lost much more quickly at a heat-shock temperature than a normal growth temperature. In a cell, the activity was restored within 45 min after a heat-shock by the heat-induced synthesis and stabilization of a DNA-binding protein. It is proposed that the inverted repeat is a specific target for a DNA-binding protein and that it plays a role in the regulation of the cyanobacterial hspA gene expression.
AB - Previously, it was shown that transcription of the small heat-shock protein gene, hspA, from the thermophilic cyanobacterium Synechococcus vulcanus is transiently heat-inducible at a vegetative promoter that lacks any known regulatory DNA elements. A novel regulatory mechanism that suppresses the expression of hspA under non-heat-shock condition has been postulated. In this study, it is demonstrated that a protein(s) in the extract of unstressed cells of the thermophilic cyanobacterium Thermosynechococcus elongatus, a cyanobacterium closely related to S. vulcanus, specifically binds to a 5′-untranslated region of the hspA gene. An AT-rich imperfect inverted-repeat sequence (ACAAgcAAA-TTTagTTGT) as a target for a putative DNA-binding protein has been identified. The DNA-binding activity in the cell as well as in the cell extract was lost much more quickly at a heat-shock temperature than a normal growth temperature. In a cell, the activity was restored within 45 min after a heat-shock by the heat-induced synthesis and stabilization of a DNA-binding protein. It is proposed that the inverted repeat is a specific target for a DNA-binding protein and that it plays a role in the regulation of the cyanobacterial hspA gene expression.
KW - Cyanobacterium
KW - DNA binding protein
KW - Inverted repeat
KW - Repressor
KW - Small heat-shock protein
KW - Thermophile
KW - Thermosynechococcus elongatus
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U2 - 10.1016/S0006-291X(02)02256-8
DO - 10.1016/S0006-291X(02)02256-8
M3 - Article
C2 - 12270139
AN - SCOPUS:0036392338
VL - 297
SP - 616
EP - 624
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
SN - 0006-291X
IS - 3
ER -