TY - JOUR
T1 - Rtt106p is a histone chaperone involved in heterochromatin-mediated silencing
AU - Huang, Shengbing
AU - Zhou, Hui
AU - Katzmann, David
AU - Hochstrasser, Mark
AU - Atanasova, Elena
AU - Zhang, Zhiguo
PY - 2005/9/20
Y1 - 2005/9/20
N2 - Epigenetic inheritance of heterochromatin structure is an important cellular process whose mechanism remains elusive. In this article, we describe the identification of nine enhancers of the silencing defect of a Saccharomyces cerevisae-PCNA mutant by screening a library of ≈4,700 viable yeast deletion mutants. Of the nine mutants identified, six (hir1, hir3, sas2, sas4, sas5, and sir1) were previously known to reduce silencing synergistically with a mutation in Cac1p, the large subunit of chromatin assembly factor 1 (CAF-1). The predicted gene products that are affected in three other mutants (nam7, msh2, and rtt106) have not been implicated previously in silencing. Characterization of the rtt106Δ allele revealed that it synergistically reduced heterochromatin silencing when combined with a mutation in Cac1p but not with a mutation in Asf1p (a histone H3 and H4 chaperone). Moreover, Rtt106p interacted with histories H3 and H4 both in vitro and in vivo, and it displayed a nucleosome assembly activity in vitro. Furthermore, Rtt106p interacts with CAF-1 physically through Cac1p. These biochemical and genetic data indicate that Rtt106p is a previously uncharacterized histone chaperone connecting S phase to epigenetic inheritance.
AB - Epigenetic inheritance of heterochromatin structure is an important cellular process whose mechanism remains elusive. In this article, we describe the identification of nine enhancers of the silencing defect of a Saccharomyces cerevisae-PCNA mutant by screening a library of ≈4,700 viable yeast deletion mutants. Of the nine mutants identified, six (hir1, hir3, sas2, sas4, sas5, and sir1) were previously known to reduce silencing synergistically with a mutation in Cac1p, the large subunit of chromatin assembly factor 1 (CAF-1). The predicted gene products that are affected in three other mutants (nam7, msh2, and rtt106) have not been implicated previously in silencing. Characterization of the rtt106Δ allele revealed that it synergistically reduced heterochromatin silencing when combined with a mutation in Cac1p but not with a mutation in Asf1p (a histone H3 and H4 chaperone). Moreover, Rtt106p interacted with histories H3 and H4 both in vitro and in vivo, and it displayed a nucleosome assembly activity in vitro. Furthermore, Rtt106p interacts with CAF-1 physically through Cac1p. These biochemical and genetic data indicate that Rtt106p is a previously uncharacterized histone chaperone connecting S phase to epigenetic inheritance.
KW - Chromosome assembly factor 1
KW - Epigenetic silencing
KW - Nucleosome assembly
UR - http://www.scopus.com/inward/record.url?scp=26444591572&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=26444591572&partnerID=8YFLogxK
U2 - 10.1073/pnas.0506176102
DO - 10.1073/pnas.0506176102
M3 - Article
C2 - 16157874
AN - SCOPUS:26444591572
SN - 0027-8424
VL - 102
SP - 13410
EP - 13415
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
IS - 38
ER -