The MYST family comprises five enzymes: MOZ, Tip60, MOF, MORF, and HBO1
. This family is characterized by the presence of a highly conserved 370-residue MYST domain and other domains relevant for the recognition of other proteins [28, 29].
Hbo1, a histone acetyltransferase binding to origin recognition complex (ORC1), (17) regulates histone acetylation, (18-20) replicational licensing, (21,22) origin activation, (23) adipogenesis, (24) pluripotency and self-renewal of embryonic stem cells, (25) and chromatin assembly of centromeres.
Here we investigated molecular mechanism of the promoted ubiquitination of ER[alpha] by Hbo1. The ligand-binding domain (LBD) of ER[alpha] was ubiquitinated by Hbo1.
The recombinant KAT7 (Hbo1 purified from Sf9 cells), MurFl, GST-tagged p53, and ubiquitin proteins were purchased from Active Motif (Carlsbad, CA, USA), R&D systems (Minneapolis, MN, USA), EMD Millipore (Temecula, CA, USA) and UBPBio (Aurora, CO, USA), respectively.
The His-tagged full-length human Hbo1 (amino acids: 1-611) protein was purified on Heparin Sepharose (GE Healthcare, Little Chalfont, UK), whereas His-Hbo1 (amino acids: 225-611) and His-Hbo1 (amino acids: 311-611) proteins (28) were purified on Ni-NTA Agarose (Qiagen, Hilden, Germany).
(34) siRNAs for Hbo1 targeted nucleotide 92 of the coding sequences of Hbo1.
Hbo1. To map sites of ER[alpha] ubiquitination promoted by Hbo1, deletion mutants of ER[alpha] were constructed (Fig.
Bewkes oversees a domestic operation that includes four HBO channels - HBO1
, HBO2, HBO3 and HBO Family - and three channels of its sister net Cinemax.
Intrinsic ubiquitin E3 ligase activity of histone acetyltransferase Hbo1
for estrogen receptor [alpha] Masayoshi IIZUKA, Takao SUSA, Mimi TAMAMORI-ADACHI, Hiroko OKINAGA and Tomoki OKAZAKI Communicated by Takao SEKIYA, M.J.A.