TY - JOUR
T1 - Yeast Isw1p forms two separable complexes in vivo
AU - Vary, Jay C.
AU - Gangaraju, Vamsi K.
AU - Qin, Jun
AU - Landel, Carolyn Church
AU - Kooperberg, Charles
AU - Bartholomew, Blaine
AU - Tsukiyama, Toshio
PY - 2003/1
Y1 - 2003/1
N2 - There are several classes of ATP-dependent chromatin remodeling complexes, which modulate the structure of chromatin to regulate a variety of cellular processes. The budding yeast, Saccharomyces cerevisiae, encodes two ATPases of the ISWI class, Isw1p and Isw2p. Previously Isw1p was shown to copurify with three other proteins. Here we identify these associated proteins and show that Isw1p forms two separable complexes in vivo (designated Isw1a and Isw1b). Biochemical assays revealed that while both have equivalent nucleosome-stimulated ATPase activities, Isw1a and Isw1b differ in their abilities to bind to DNA and nucleosomal substrates, which possibly accounts for differences in specific activities in nucleosomal spacing and sliding. In vivo, the two Isw1 complexes have overlapping functions in transcriptional regulation of some genes yet distinct functions at others. In addition, these complexes show different contributions to cell growth at elevated temperatures.
AB - There are several classes of ATP-dependent chromatin remodeling complexes, which modulate the structure of chromatin to regulate a variety of cellular processes. The budding yeast, Saccharomyces cerevisiae, encodes two ATPases of the ISWI class, Isw1p and Isw2p. Previously Isw1p was shown to copurify with three other proteins. Here we identify these associated proteins and show that Isw1p forms two separable complexes in vivo (designated Isw1a and Isw1b). Biochemical assays revealed that while both have equivalent nucleosome-stimulated ATPase activities, Isw1a and Isw1b differ in their abilities to bind to DNA and nucleosomal substrates, which possibly accounts for differences in specific activities in nucleosomal spacing and sliding. In vivo, the two Isw1 complexes have overlapping functions in transcriptional regulation of some genes yet distinct functions at others. In addition, these complexes show different contributions to cell growth at elevated temperatures.
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U2 - 10.1128/MCB.23.1.80-91.2003
DO - 10.1128/MCB.23.1.80-91.2003
M3 - Article
C2 - 12482963
AN - SCOPUS:0037214318
SN - 0270-7306
VL - 23
SP - 80
EP - 91
JO - Molecular and cellular biology
JF - Molecular and cellular biology
IS - 1
ER -