RELT Like Protein 1 (RELL1)

The predicted RELL1 sequence contains a transmembrane domain but lacks extracellular cysteine-rich domains. RELL1 shares 32% and 40% amino acid identity with RELT and RELL2, respectively. Northern blot analysis detected an approximately 4-kb transcript in all human tissues examined with highest expression in placenta, spleen, skeletal muscle, and testis. Immunofluorescent confocal microscopy localized RELL1 to the plasma membrane in COS-7 cells and colocalized RELL1 with RELL2 and RELT.

Coimmunoprecipitation studies showed that RELL1 interacted with RELL2, RELT, and OSR1. By in vitro kinase assay, Cusick et al. (2006) showed that RELL1, RELL2, and RELT were phosphorylated by OSR1.