Mahogunin Ring Finger Protein 1 (MGRN1)

'Mahoganoid' is a mouse coat color mutation whose pigmentary phenotype and genetic interactions resemble those of 'mahogany,' which results from mutation in attractin (ATRN).

Human and mouse mahogunin share 95% amino acid sequence identity and exhibit a similar expression pattern across multiple tissues with particularly high levels in brain. The RING domain functions as an E3 ubiquitin ligase, and autoubiquitination is dependent on ATP, E1, E2, and an intact mahogunin RING domain, with ladder formation proportional to the amounts. In addition, mahogunin-induced autoubiquitination exhibited specificity for E2; it occurred with UBC5, used frequently in the stress response to unfolded proteins, but not with UBC3, used frequently in cell cycle transitions.