Functional conservation between mammalian MGRN1 and plant LOG2 ubiquitin ligases

Plant LOSS OF GDU 2 (LOG2) and Mammalian Mahogunin Ring Finger 1 (MGRN1) proteins are RING-type E3 ligases sharing similarity N-terminal to the RING domain. Deletion of this region disrupts the interaction of LOG2 with the plant membrane protein GLUTAMINE DUMPER1 (GDU1). Phylogenetic analysis identified two clades of LOG2/MGRN1-like proteins in vertebrates and plants. The ability of MGRN1 to functionally replace LOG2 was tested. MGRN1 ubiquitylates GDU1 in vitro and can partially substitute for LOG2 in the plant, partially restoring amino acid resistance to a GDU1-myc over-expression, log2-2 background. Altogether, these results suggest a conserved function for the N-terminal domain in evolution. Structured summary of protein interactions: GDU1 physically interacts with rnMGRN1 by two hybrid (1, 2) rnMGRN1 binds to GDU1 by pull down (View interaction) GDU6 physically interacts with rnMGRN1 by two hybrid (1, 2) GDU3 physically interacts with hsMGRN1 by two hybrid (1, 2) rnMGRN1 physically interacts with GDU7 by two hybrid (1, 2) GDU5 physically interacts with hsMGRN1 by two hybrid (1, 2) hsMGRN1 physically interacts with GDU1 by two hybrid (1, 2) rnMGRN1 physically interacts with GDU3 by two hybrid (1, 2) rnMGRN1 physically interacts with GDU5 by two hybrid (1, 2) hsMGRN1 physically interacts with GDU7 by two hybrid (1, 2) GDU6 physically interacts with hsMGRN1 by two hybrid (1, 2) LOG2 binds to GDU1 by pull down (1, 2) hsMGRN1 physically interacts with GDU4 by two hybrid (1, 2) rnMGRN1 physically interacts with GDU2 by two hybrid (1, 2) GDU4 physically interacts with rnMGRN1 by two hybrid (1, 2) LOG2 physically interacts with GDU1 by two hybrid (1, 2, 3, 4) GDU2 physically interacts with hsMGRN1 by two hybrid (1, 2) (C) 2013 Federation of European Biochemical Societies. Published by Elsevier B. V. All rights reserved.