CIITA, C2TA, CIITAIV, MHC2TA, NLRA, class II, major histocompatibility complex, transactivator, class II major histocompatibility complex transactivator
CIITA
mRNA can only be detected in
human leukocyte antigen (HLA) system class II-positive cell lines and tissues. This highly restricted tissue distribution suggests that expression of HLA class II genes is to a large extent under the control of CIITA.[7] However, CIITA does not appear to directly bind to DNA.[7] Instead CIITA functions through activation of the
transcription factorRFX5.[8] Hence CIITA is classified as a transcriptional
coactivator.
The CIITA protein contains an acidic
transcriptional activation domain, 4 LRRs (
leucine-rich repeats) and a
GTP binding domain.[9] The protein uses GTP binding to facilitate its own transport into the nucleus.[10] Once in the nucleus, the protein acts as a positive regulator of class II major histocompatibility complex
gene transcription, and is often referred to as the "master control factor" for the expression of these genes.[11][12]
^"Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^"Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^
abSteimle V, Otten LA, Zufferey M, Mach B (Oct 1993). "Complementation cloning of an MHC class II transactivator mutated in hereditary MHC class II deficiency (or bare lymphocyte syndrome)". Cell. 75 (1): 135–46.
doi:
10.1016/S0092-8674(05)80090-X.
PMID8402893.
S2CID30276144.
^Harton JA, Cressman DE, Chin KC, Der CJ, Ting JP (Aug 1999). "GTP binding by class II transactivator: role in nuclear import". Science. 285 (5432): 1402–5.
doi:
10.1126/science.285.5432.1402.
PMID10464099.