KMT2A Gene

The KMT2A gene (lysine methyltransferase 2A) encodes a transcriptional coactivator located on chromosome 11q23.3.

The protein encoded by the KMT2A gene, lysine methyltransferase 2A, plays an essential role in the regulation of gene expression during early development and hematopoiesis. It contains several conserved functional domains. One of these domains, the SET domain, is responsible for histone H3 lysine 4 (H3K4) methyltransferase activity, which mediates chromatin modifications associated with epigenetic transcriptional activation.

Histone methyltransferase plays an essential role in early development and hematopoiesis. Promotes PPP1R15A-induced apoptosis. Plays a critical role in the control of circadian gene expression and is essential for transcriptional activation mediated by the CLOCK-ARNTL/BMAL1 heterodimer. Provides a permissive chromatin state for circadian transcription by mediating rhythmic methylation of "Lys-4" of histone H3 (H3K4me).

The transcriptional coactivator KMT2A is cleaved by the enzyme taspase 1 into two fragments: MLL-C and MLL-N. These fragments reassociate and assemble into various multiprotein complexes that regulate the transcription of specific target genes, including many HOX genes.

Several chromosomal translocations involving this gene are the cause of certain forms of acute lymphoblastic leukemias (Panagopoulos I et al. 2021) and acute myeloid leukemias (AML).

Diseases associated with KMT2A include:

• Wiedemann-Steiner syndrome
• and
• acute myeloid leukemia.

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