title: The carboxyl terminus of Rtt109 functions in chaperone control of histone acetylation.
abstract: Rtt109 is a fungal histone acetyltransferase (HAT) that catalyzes histone H3 acetylation functionally associated with chromatin assembly. Rtt109-mediated H3 acetylation involves two histone chaperones, Asf1 and Vps75. In vivo, Rtt109 requires both chaperones for histone H3 lysine 9 acetylation (H3K9ac) but only Asf1 for full H3K56ac. In vitro, Rtt109-Vps75 catalyzes both H3K9ac and H3K56ac, whereas Rtt109-Asf1 catalyzes only H3K56ac. In this study, we extend the in vitro chaperone-associated substrate specificity of Rtt109 by showing that it acetylates vertebrate linker histone in the presence of Vps75 but not Asf1. In addition, we demonstrate that in Saccharomyces cerevisiae a short basic sequence at the carboxyl terminus of Rtt109 (Rtt109C) is required for H3K9ac in vivo. Furthermore, through in vitro and in vivo studies, we demonstrate that Rtt109C is required for optimal H3K56ac by the HAT in the presence of full-length Asf1. When Rtt109C is absent, Vps75 becomes important for H3K56ac by Rtt109 in vivo. In addition, we show that lysine 290 (K290) in Rtt109 is required in vivo for Vps75 to enhance the activity of the HAT. This is the first in vivo evidence for a role for Vps75 in H3K56ac. Taken together, our results contribute to a better understanding of chaperone control of Rtt109-mediated H3 acetylation.
authors: Department of Chemistry and Biology, Ryerson University, Toronto, Ontario, Canada.
authors: Ernest
authors: E
authors: Radovani
authors: Matthew
authors: M
authors: Cadorin
authors: Tahireh
authors: T
authors: Shams
authors: Suzan
authors: S
authors: El-Rass
authors: Abdel R
authors: AR
authors: Karsou
authors: Hyun-Soo
authors: HS
authors: Kim
authors: Christoph F
authors: CF
authors: Kurat
authors: Michael-Christopher
authors: MC
authors: Keogh
authors: Jack F
authors: JF
authors: Greenblatt
authors: Jeffrey S
authors: JS
authors: Fillingham
mesh_terms: D000107:Acetylation; D000595:Amino Acid Sequence; D000818:Animals; D030161:Avian Proteins / Q000737:chemistry; D020134:Catalytic Domain; D018797:Cell Cycle Proteins / Q000737:chemistry; D002645:Chickens; D055786:Gene Knockout Techniques; D051548:Histone Acetyltransferases / Q000737:chemistry / Q000502:physiology*; D006657:Histones / Q000737:chemistry / Q000378:metabolism*; D008239:Lysine / Q000378:metabolism; D018832:Molecular Chaperones / Q000737:chemistry / Q000378:metabolism; D008969:Molecular Sequence Data; D011485:Protein Binding; D011499:Protein Processing, Post-Translational; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*
chemical_list: C109731:ASF1 protein, S cerevisiae; D030161:Avian Proteins; D018797:Cell Cycle Proteins; D006657:Histones; D018832:Molecular Chaperones; D029701:Saccharomyces cerevisiae Proteins; C525548:Vps75 protein, S cerevisiae; D051548:Histone Acetyltransferases; C517120:Rtt109 protein, S cerevisiae; D008239:Lysine