This entry represents the Tudor domain found in BAHCC1 and TNRC18 from mammals and winged eye, the orthologue from Drosophila [2]. BAHCC1, may function as a transcriptional regulator. BAHCC1 contains a Tudor domain and a C-terminal BAH domain. This protein specifically recognises H3K27me3 through its BAH module (Pfam:PF01426) and enforces silencing of H3K27me3-demarcated genes in mammalian cells [1]. TNRC18 is thought to enable chromatin binding activity, however, its function is not yet unknown. Winged eye is a factor that induces eye-to-wing transdetermination upon overexpression in eye imaginal discs. It induces various histone modifications and enhances the methylation of Lys9 on histone H3 (H3K9) [2]. This domain may be implicated in the interactions with methylated histone.

1: BAHCC1 binds H3K27me3 via a conserved BAH module to mediate gene silencing and oncogenesis. Fan H, Lu J, Guo Y, Li D, Zhang ZM, Tsai YH, Pi WC, Ahn JH, Gong W, Xiang Y, Allison DF, Geng H, He S, Diao Y, Chen WY, Strahl BD, Cai L, Song J, Wang GG; Nat Genet. 2020;52:1384-1396. PMID:33139953

2: winged eye Induces Transdetermination of Drosophila Imaginal Disc by Acting in Concert with a Histone Methyltransferase, Su(var)3-9. Masuko K, Fuse N, Komaba K, Katsuyama T, Nakajima R, Furuhashi H, Kurata S; Cell Rep. 2018;22:206-217. PMID:29298422