This family contains sequences that are similar to the N-terminal region of Red protein (Swiss:Q13123). This and related proteins contain a RED repeat which consists of a number of RE and RD sequence elements [1]. The region in question has several conserved NLS sequences and a putative trimeric coiled-coil region [1], suggesting that these proteins are expressed in the nucleus [1]. The function of Red protein is unknown, but efficient sequestration to nuclear bodies suggests that its expression may be tightly regulated of that the protein self-aggregates extremely efficiently [1].

1: Isolation, sequencing and expression of RED, a novel human gene encoding an acidic-basic dipeptide repeat. Assier E, Bouzinba-Segard H, Stolzenberg MC, Stephens R, Bardos J, Freemont P, Charron D, Trowsdale J, Rich T; Gene 1999;230:145-154. PMID:10216252