3uxg

Structural highlights

Disease

[RFXK_HUMAN] Immunodeficiency by defective expression of HLA class 2. The disease is caused by mutations affecting the gene represented in this entry.^{[1] [2] [3]} [HDAC4_HUMAN] Defects in HDAC4 are the cause of brachydactyly-mental retardation syndrome (BDMR) [MIM:600430]. A syndrome resembling the physical anomalies found in Albright hereditary osteodystrophy. Common features are mild facial dysmorphism, congenital heart defects, distinct brachydactyly type E, mental retardation, developmental delay, seizures, autism spectrum disorder, and stocky build. Soft tissue ossification is absent, and there are no abnormalities in parathyroid hormone or calcium metabolism.^[4]

Function

[RFXK_HUMAN] Activates transcription from class II MHC promoters. Activation requires the activity of the MHC class II transactivator (MHC2TA). May regulate other genes in the cell. RFX binds the X1 box of MHC-II promoters. Isoform RFX-B-delta5 is not involved in the positive regulation of MHC class II genes. [HDAC4_HUMAN] Responsible for the deacetylation of lysine residues on the N-terminal part of the core histones (H2A, H2B, H3 and H4). Histone deacetylation gives a tag for epigenetic repression and plays an important role in transcriptional regulation, cell cycle progression and developmental events. Histone deacetylases act via the formation of large multiprotein complexes. Involved in muscle maturation via its interaction with the myocyte enhancer factors such as MEF2A, MEF2C and MEF2D.^[5]

References

1. ↑ Masternak K, Barras E, Zufferey M, Conrad B, Corthals G, Aebersold R, Sanchez JC, Hochstrasser DF, Mach B, Reith W. A gene encoding a novel RFX-associated transactivator is mutated in the majority of MHC class II deficiency patients. Nat Genet. 1998 Nov;20(3):273-7. PMID:9806546 doi:http://dx.doi.org/10.1038/3081
2. ↑ Nagarajan UM, Louis-Plence P, DeSandro A, Nilsen R, Bushey A, Boss JM. RFX-B is the gene responsible for the most common cause of the bare lymphocyte syndrome, an MHC class II immunodeficiency. Immunity. 1999 Feb;10(2):153-62. PMID:10072068
3. ↑ Nagarajan UM, Peijnenburg A, Gobin SJ, Boss JM, van den elsen PJ. Novel mutations within the RFX-B gene and partial rescue of MHC and related genes through exogenous class II transactivator in RFX-B-deficient cells. J Immunol. 2000 Apr 1;164(7):3666-74. PMID:10725724
4. ↑ Williams SR, Aldred MA, Der Kaloustian VM, Halal F, Gowans G, McLeod DR, Zondag S, Toriello HV, Magenis RE, Elsea SH. Haploinsufficiency of HDAC4 causes brachydactyly mental retardation syndrome, with brachydactyly type E, developmental delays, and behavioral problems. Am J Hum Genet. 2010 Aug 13;87(2):219-28. doi: 10.1016/j.ajhg.2010.07.011. PMID:20691407 doi:10.1016/j.ajhg.2010.07.011
5. ↑ Wang AH, Bertos NR, Vezmar M, Pelletier N, Crosato M, Heng HH, Th'ng J, Han J, Yang XJ. HDAC4, a human histone deacetylase related to yeast HDA1, is a transcriptional corepressor. Mol Cell Biol. 1999 Nov;19(11):7816-27. PMID:10523670
6. ↑ Xu C, Jin J, Bian C, Lam R, Tian R, Weist R, You L, Nie J, Bochkarev A, Tempel W, Tan CS, Wasney GA, Vedadi M, Gish GD, Arrowsmith CH, Pawson T, Yang XJ, Min J. Sequence-Specific Recognition of a PxLPxI/L Motif by an Ankyrin Repeat Tumbler Lock. Sci Signal. 2012 May 29;5(226):ra39. PMID:22649097 doi:10.1126/scisignal.2002979