Anti-Histone Methyltransferase SUV39H1

In eukaryotic cells the histone methylase KMT1A / SUV39H1 and the methyl-lys binding protein HP1 interact to repress transcription at heterochromatic sites. Lys 9 of histone H3 is methylated by KMT1A, creating a binding site for the chromo domain of HP1. The Lys methylase activity of KMT1A resides in the SET domain. KMT1A and HP1 are both involved in the repressive functions of the retinoblastoma (Rb) protein. KMT1A cooperates with Rb to repress the cyclin E promoter, and in fibrobroblasts that are disrupted for KMT1A, the activity of the cyclin E and cyclin A2 genes are specifcally elevated. Chromatin IPs (ChIPs) show that Rb is necessary to direct methylation of histone H3, and is necessary for binding of HP1 to the cyclin E promoter. The KMT1A-HP1 complex is thus not only involved in heterochromatic silencing but also has a role in repression of euchromatic genes by Rb and perhaps other co-repressor proteins. Histone H3 lysine 9 can be mono, di or tri methylated. Different HMTases have recently been found responsible for each modification state. G9a is thought to be responsible for all mono and di methylation of H3 K9 in slient regions of heterochromatin. In contrast, KMT1A and H2 are thought to be responsible fro the tri methylation of H3K9 found in pericentric heterochromatin. Applications: Suitable for use in ELISA, Western Blot and Immunoprecipitation. Other applications not tested. Recommended Dilutions: Western Blot: 2-4ug/ml using extract of HeLa nuclear cells. , Optimal dilutions to be determined by the researcher. Storage and Stability: May be stored at 4°C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Aliquots are stable for 12 months. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.