Myocyte enhancer binding factor 2B (MEF2B) is a transcription factor part of the MEF2 gene family including MEF2A, MEF2C, and MEF2D.[2][3] However, MEF2B is distant from the other three branches of MEF2 genes as it lacks the protein-coding Holliday junction recognition protein C-terminal (HJURP_C) region in vertebrates.[4]
Functions
The MEF2 gene family is expressed in muscle-specific gene activation and maintenance during development.[4][5] MEF2B mRNA is present in skeletal, smooth, brain and heart muscles.[6] MEF2B is directly involved in smooth muscle myosin heavy chain (SMHC) gene regulation. Overexpression of MEF2B will activate the SMHC promoter in smooth muscle when it is bound to the A/T-rich element of the promoter.[6]
Recurrent mutations in this gene have been associated with cases of diffuse large B-cell lymphoma.[9] In its mutated form, MEF2B can lead to deregulation of the proto-oncogene BCL6 expression in diffuse large B-cell lymphomas (DLBCL).[10] Mutations of MEF2B enhance its transcriptional activity due to either a disruption with its corepressor CABIN1 or causing the gene to become insensitive to inhibitory signaling events.[10]
^Buchberger A, Arnold HH (June 1999). "The MADS domain containing transcription factor cMef2a is expressed in heart and skeletal muscle during embryonic chick development". Development Genes and Evolution. 209 (6): 376–381. doi:10.1007/s004270050267. PMID10370120. S2CID2819535.
^Youn HD, Sun L, Prywes R, Liu JO (October 1999). "Apoptosis of T cells mediated by Ca2+-induced release of the transcription factor MEF2". Science. 286 (5440): 790–793. doi:10.1126/science.286.5440.790. PMID10531067.
Hobson GM, Krahe R, Garcia E, Siciliano MJ, Funanage VL (October 1995). "Regional chromosomal assignments for four members of the MADS domain transcription enhancer factor 2 (MEF2) gene family to human chromosomes 15q26, 19p12, 5q14, and 1q12-q23". Genomics. 29 (3): 704–711. doi:10.1006/geno.1995.9007. PMID8575763.
Youn HD, Sun L, Prywes R, Liu JO (October 1999). "Apoptosis of T cells mediated by Ca2+-induced release of the transcription factor MEF2". Science. 286 (5440): 790–793. doi:10.1126/science.286.5440.790. PMID10531067.
Han A, He J, Wu Y, Liu JO, Chen L (January 2005). "Mechanism of recruitment of class II histone deacetylases by myocyte enhancer factor-2". Journal of Molecular Biology. 345 (1): 91–102. doi:10.1016/j.jmb.2004.10.033. PMID15567413.