The nuclear actin-related proteins, Arp7 and Arp9: connecting ARP hetertodimerization to the regulation of chromatin remodling.

Update Item Information
Publication Type dissertation
School or College School of Medicine
Department Oncological Sciences
Author Szerlong, Heather.
Title The nuclear actin-related proteins, Arp7 and Arp9: connecting ARP hetertodimerization to the regulation of chromatin remodling.
Date 2004-08
Description Actin-related proteins (ARPs) belong to the actin superfamily of proteins with diverse functions in both the cytoplasm and the nucleus. ARPs share limited sequence similarity to actin, but have conserved the 'actin-fold' utilized by actin for ATP binding and hydrolysis. Intriguingly, nuclear ARPs and actin are members of two types of chromatin modifying complexes; chromatin remodeling complexes that mobilize nucleosomes in an ATP-dependent manner and histone acetyltransferase (HAT) complexes that posttranslationally modify nucleosomes by covalently linking an acetyl group to lysine residues on histones. Although ARPs/actin are not subunits of all types of remodelers and HATs, they are found in particular families, including the SWI/SNF family of remodelers and the MYST family of HATS. The central question is: how are ARPs utilized in the regulation of chromatin structure? Heterodimerization is an essential property of cytoplasmic ARPs in the cytoskeleton. Our work reveals Arp7 and Arp9 as obligate heterodimers both physically and functionally, as dimerization is a prerequisite for their assembly into the related RSC and SWI/SNF remodeling complexes in S. cerevisiae . Additionally, we found that Arp7 and Arp9 interact with two regulators of chromatin structure including Nhp6 (n[barbelow]on-h[barbelow]istone p[barbelow]rotein 6[barbelow]), an HMG-box architectural factor, and Sth1, the catalytic subunit (DNA translocase) of RSC. arp7/arp9 conditional alleles were partially suppressed by overexpression of NHP6 suggesting a role for ARPs in the regulation of promoter architecture. Arp7/Arp9-mediated regulation of chromatin structure may be through their association with RSC, as mutations in either the ATPase domain or the HSA (helicase/SANT-associated) domain of Sth1 resulted in the partial bypass of Arp7/Arp9 function. Taken together, our data suggest that Arp7/Arp9 dimers cooperate with particular domains of Sth1 in the regulation of the RSC complex.
Type Text
Publisher University of Utah
Subject Purification; Mutations
Subject MESH Actins; Chromatin
Dissertation Institution University of Utah
Dissertation Name PhD
Language eng
Relation is Version of Digital reproduction of "The nuclear actin-related proteins, Arp7 and Arp9: connecting ARP hetertodimerization to the regulation of chromatin remodling.." Spencer S. Eccles Health Sciences Library. Print version of "The nuclear actin-related proteins, Arp7 and Arp9: connecting ARP hetertodimerization to the regulation of chromatin remodling." available at J. Willard Marriott Library Special Collection. QP6.5 2004 .S94.
Rights Management © Heather Szerlong.
Format Medium application/pdf
Identifier us-etd2,101
Source Original: University of Utah Spencer S. Eccles Health Sciences Library (no longer available).
Funding/Fellowship National Institutes of Health (GM60415 to B.R.C.; CA324014 for core facilities) and the Howard Hughes Medical Institue.
ARK ark:/87278/s64m9k63
Setname ir_etd
ID 194040
Reference URL https://collections.lib.utah.edu/ark:/87278/s64m9k63