This LDXXLDAYM region (where X is any amino acid) is duplicated in the C terminus of chromatin target of PRMT1 protein (also known as Fop), which are chromatin-associated proteins that co-localise with facultative heterochromatin and are critical for oestrogen-dependent gene activation []. The region also occurs in other proteins, including THO complex subunit 4 () and RNA and export factor-binding protein 2 ().
BTG1 is a member of the BTG/Tob family. It regulates cell cycle progression, inhibits proliferation, promotes apoptosis and stimulates cellular differentiation in multiple cell types. It may inhibit cell growth and promote apoptosis by interacting with PRMT1 (protein arginine N-methyltransferase 1) in renal cell carcinoma []. In mice, it plays a critical role for cerebellar maturation and function [].The BTG/Tob family members contain an conserved N-terminal domain, known as APRO domain (AntiPROliferative) or BTG domain. In mammals, six family members have been identified: BTG1, BTG2/PC3/Tis21, BTG3/ANA, BTG4/PC3B, Tob1/Tob and Tob2. They interact with CAF1, a subunit of the CCR4-NOT complex. They display antiproliferative properties as their ectopic expression in a variety of cell lines reduced cell proliferation [].
