text: MYST family MOZ (Monocytic Leukemia Zinc Finger Protein), Ybf2/Sas3, Sas2 and Tip60 (Tat Interacting Protein) all make up MYST, another well known family that exhibits acetylating capabilities. This family includes Sas3, essential SAS-related acetyltransferase (Esa1), Sas2, Tip60, MOF, MOZ, MORF, and HBO1. The members of this family have multiple functions, not only with activating and silencing genes, but also affect development and have implications in human diseases. Sas2 and Sas3 are involved in transcription silencing, MOZ and TIF2 are involved with the formation of leukemic transclocation products while MOF is involved in dosage compensation in Drosophila.  MOF also influences spermatogenesis in mice as it is involved in the expansion of H2AX phosphorylation during the leptotene to pachytene stages of meiosis. HAT domains for this family are approximately 250 residues which include cysteine-rich, zinc binding domains as well as N-terminal chromodomains. The MYST proteins Esa1, Sas2 and Sas3 are found in yeast, MOF is found in Drosophila and mice while Tip60, MOZ, MORF, and HBO1 are found in humans. Tip60 has roles in the regulation of gene transcription, HBO has been found to impact the DNA replication process, MORF is able to acetylate free histones (especially H3 and H4) as well as nucleosomal histones.
  p300/CBP family
  Adenoviral E1A-associated protein of 300kDa (p300) and the CREB-binding protein (CBP) make up the next family of HATs. This family of HATs contain HAT domains that are approximately 500 residues long and contain bromodomains as well as three cysteine-histidine rich domains that help with protein interactions. These HATs are known to acetylate all of the histone subunits in the nucleosome. They also have the ability to acetylate and mediate non-histone proteins involved in transcription and are also involved in the cell-cycle, differentiation and apoptosis.
  Other HATs
  There are other proteins that have acetylating abilities but differ in structure to the previously mentioned families. One HAT is called steroid receptor coactivator 1 (SRC1), which has a HAT domain located at the C-terminus end of the protein along with a basic helix-loop-helix and PAS A and PAS B domains with a LXXLL receptor interacting motif in the middle. Another is ATF-2 which contains a transcriptional activation (ACT) domain and a basic zipper DNA-binding (bZip) domain with a HAT domain in-between. The last is TAFII250 which has a Kinase domain at the N-terminus region, two bromodomains located at the C-terminus region and a HAT domain located in-between.