Affinity purification of MLL3/MLL4 histone H3K4 methyltransferase complex

Nuclear Receptor Biology Section, NIDDK, NIH, Bethesda, MD, USA.
Methods in molecular biology (Clifton, N.J.) (Impact Factor: 1.29). 01/2012; 809:465-72. DOI: 10.1007/978-1-61779-376-9_30
Source: PubMed


Methylation on histone H3 lysine 4 (H3K4) correlates with actively transcribed genes. In mammalian cells, there exist multiple Set1-like histone H3K4 methyltransferase complexes, which have overlapping but distinct subunit compositions. Developing methods to isolate each of these histone H3K4 methyltransferase complexes would help understand the molecular mechanisms by which histone H3K4 methylation regulates mammalian gene expression. In this chapter, we provide a one-step affinity purification protocol on isolation of the MLL3/MLL4 histone H3K4 methyltransferase complex using FLAG-tagged PA1, a unique subunit of the MLL3/MLL4 complex.

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Available from: Kai Ge, Apr 09, 2015
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    • "Homologous MLL3 and MLL4 belong to the mammalian SET1-like H3K4 methyltransferase family [84-86]. Each member of this family of six methyltransferases forms a large protein complex that contains WDR5, RbBP5, ASH2L, and DPY30 (WRAD) subunits [84-87]. In addition to the common WRAD subunits, MLL3/MLL4 complexes also contain unique subunits, including H3K27 demethylase UTX, nuclear receptor coactivator NCOA6, BRCT domain-containing protein PTIP, and a novel protein PA1 (also known as PAGR1) [84,88-90]. "
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    • ") (MLL3 is also known as KMT2C, and MLL4 is also known as ALR, MLL2, or KMT2D)(Cho et al., 2012). Transcription of switch regions is thought to render them in an accessible configuration that allows DNA cleavage by the enzyme activation induced deaminase (AID) (Stavnezer et al., 2008). "
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