Bin3 contains a tripartite S-adenosyl-L-methionine (SAM) bindingmotif with three sequence motifs, I/Ia, II, and III []. It is found in the following proteins:Drosophila melanogaster probable methyltransferase Bin3 (EC 2.1.1.-). It interacts with bicoid/bcd.Human 7SK snRNA methylphosphate capping enzyme (MePCE) (EC 2.1.1.-) orBicoid-interacting protein 3 homologue (Bin3 homolog), a S-adenosyl-L-methionine-dependent methyltransferase that adds a methylphosphate cap atthe 5'-end of 7SK snRNA, leading to stabilise it.Caenorhabditis elegans probable methyltransferase Y17G7B.18 (EC 2.1.1.-).This entry represents the Bin3-type SAM binding domain.
BAR domains are dimerization, lipid binding and curvature sensing modules found in many different proteins with diverse functions []. Bridging integrator 3 (Bin3) is widely expressed in many tissues except in the brain. It plays roles in regulating filamentous actin localization and in cell division. In humans, the Bin3 gene is located in chromosome 8p21.3, a region that is implicated in cancer suppression. Homozygous inactivation of the Bin3 gene in mice led to the development of cataracts and an increased likelihood of lymphomas during aging, suggesting a role for Bin3 in lens development and cancer suppression []. BAR domains form dimers that bind to membranes, induce membrane bending and curvature, and may also be involved in protein-protein interactions [].
This entry represents the C-terminal conserved region of the Drosophila probable RNA methyltransferase bin3 []. Proteins containing this domain also include human pre-miRNA 5'-monophosphate methyltransferase BCDIN3D []and 7SK snRNA methylphosphate capping enzyme MEPCE []. This domain contains a conserved HLN motif.
