Agustina Toscanini, M.; Belen Favarolo, M.; Luis Gonzalez Flecha, F.; Ebert, Berit; Rautengarten, Carsten; Bredeston, Luis M. published the artcile< Conserved Glu-47 and Lys-50 residues are critical for UDP-N-acetylglucosamine/UMP antiport activity of the mouse Golgi-associated transporter Slc35a3>, COA of Formula: C9H13N2O9P, the main research area is UDPGlcNAc UDP N acetylglucosamine UMP transporter; mouse Golgi associated transporter Slc35a3; Golgi; UDP-GlcNAc metabolism; antiporter; congenital glycosylation disorder; glycoprotein biosynthesis; membrane protein; membrane transport; secretory pathway; solute carrier family 35 member A3 (SLC35A3); structural model.
Nucleotide sugar transporters (NSTs) regulate the flux of activated sugars from the cytosol into the lumen of the Golgi apparatus where glycosyltransferases use them for the modification of proteins, lipids, and proteoglycans. It has been well-established that NSTs are antiporters that exchange nucleotide sugars with the resp. nucleoside monophosphate. Nevertheless, information about the mol. basis of ligand recognition and transport is scarce. Here, using topol. predictors, cysteine-scanning mutagenesis, expression of GFP-tagged protein variants, and phenotypic complementation of the yeast strain Kl3, we identified residues involved in the activity of a mouse UDP-GlcNAc transporter, murine solute carrier family 35 member A3 (mSlc35a3). We specifically focused on the putative transmembrane helix 2 (TMH2) and observed that cells expressing E47C or K50C mSlc35a3 variants had lower levels of GlcNAc-containing glycoconjugates than WT cells, indicating impaired UDP-GlcNAc transport activity of these two variants. A conservative substitution anal. revealed that single or double substitutions of Glu-47 and Lys-50 do not restore GlcNAc glycoconjugates. Anal. of mSlc35a3 and its genetic variants reconstituted into proteoliposomes disclosed the following: (i) all variants act as UDP-GlcNAc/UMP antiporters; (ii) conservative substitutions (E47D, E47Q, K50R, or K50H) impair UDP-GlcNAc uptake; and (iii) substitutions of Glu-47 and Lys-50 dramatically alter kinetic parameters, consistent with a critical role of these two residues in mSlc35a3 function. A bioinformatics anal. revealed that an EXXK motif in TMH2 is highly conserved across SLC35 A subfamily members, and a 3D-homol. model predicted that Glu-47 and Lys-50 are facing the central cavity of the protein.
Journal of Biological Chemistry published new progress about Golgi apparatus. 58-97-9 belongs to class tetrahydrofurans, and the molecular formula is C9H13N2O9P, COA of Formula: C9H13N2O9P.
Referemce:
Tetrahydrofuran – Wikipedia,
Tetrahydrofuran | (CH2)3CH2O – PubChem