PROSITE logo
Black ribbon
We are deeply saddened by the passing of Amos Bairoch (1957–2025), the creator of PROSITE. We wish to dedicate our latest paper, published shortly before his death, to him. He will always be a source of inspiration to us.
Our deepest condolences go out to his family and friends, and to all those who had the privilege of working with him. Rest in peace, Amos. Your work will live on long after you are gone.
Amos Bairoch

PROSITE documentation PDOC52003
OCA domain profile


View entry in original PROSITE document format
View entry in raw text format (no links)
PURL: https://purl.expasy.org/prosite/documentation/PDOC52003

Description

The 23 amino acid OCA domain, which binds to class II POU domain-containing transcription factors (TFs) and a DNA octamer motif in a bivalent manner, are found in the POU2AF family of coactivators [1,2]:

  • Vertebrate POU2AF1 (OBF-1, Bob1, OCA-B), a B-cell specific coactivator of class II POU TFs POU2F1 (Oct-1) and POU2F2 (Oct-2).
  • Vertebrate POU2AF2 (C11orf53, OCA-T1), a tuft cell specific coactivator of class II POU TF POU2F3 (Oct-11).
  • Vertebrate POU2AF3 (COLCA2, OCA-T2), a tuft cell specific coactivator of class II POU TF POU2F3 (Oct-11).

An OCA domain is also found in another family of cofactors, the nuclear factor (NF)-kappaB inhibitor zeta (IkappaBzeta) proteins, NF-kappaB regulators which function not only as repressors but also as activators of a selective subset of NF-kappaB target genes [3].

The OCA domain is made of a N-terminal extended polypeptide strand and a C-terminal two-turn α helix (see <PDB:1CQT>) [1].

The profile we developed covers the entire OCA domain.

Last update:

July 2022 / First entry.

-------------------------------------------------------------------------------


Technical section

PROSITE method (with tools and information) covered by this documentation:

OCA, PS52003; OCA domain profile  (MATRIX)


References

1AuthorsChasman D. Cepek K. Sharp P.A. Pabo C.O.
TitleCrystal structure of an OCA-B peptide bound to an Oct-1 POU domain/octamer DNA complex: specific recognition of a protein-DNA interface.
SourceGenes. Dev. 13:2650-2657(1999).
PubMed ID10541551
DOI10.1101/gad.13.20.2650

2AuthorsWu X.S. He X.-Y. Ipsaro J.J. Huang Y.-H. Preall J.B. Ng D. Shue Y.T. Sage J. Egeblad M. Joshua-Tor L. Vakoc C.R.
TitleOCA-T1 and OCA-T2 are coactivators of POU2F3 in the tuft cell lineage.
SourceNature 607:169-175(2022).
PubMed ID35576971
DOI10.1038/s41586-022-04842-7

3AuthorsMueller A. Hennig A. Lorscheid S. Grondona P. Schulze-Osthoff K. Hailfinger S. Kramer D.
TitleIkappaBzeta is a key transcriptional regulator of IL-36-driven psoriasis-related gene expression in keratinocytes.
SourceProc. Natl. Acad. Sci. U. S. A. 115:10088-10093(2018).
PubMed ID30224457
DOI10.1073/pnas.1801377115



PROSITE is copyrighted by the SIB Swiss Institute of Bioinformatics and distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives (CC BY-NC-ND 4.0) License, see prosite_license.html.