01631nas a2200181   4500008004100000022001400041245010800055210006900163260007100232300001200303490000600315520092400321100001601245700002001261700002001281700002201301856012601323       2016                        eng d  a2161-165300aControlled synthesis of end-functionalized mannose-6-phosphate glycopolypeptides for lysosome targeting0 aControlled synthesis of endfunctionalized mannose6phosphate glyc  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJUL  a809-8130 v53 a<p>The ubiquitous expression of the mannose-6-phosphate receptor on the majority of human cells makes it a valid target in the quest to deliver therapeutics selectively to the lysosome. In this work end-functionalized polyvalent mannose-6-phosphate glycopolypeptides (M6P-GPs) with high molecular weights (up to 22 kDa) have been synthesized via NCA polymerization. These synthetic M6P-GPs were found to display minimal toxicity to cells in vitro and show exceptional selectivity for trafficking into lysosomes in various cell lines. Comparison of the cellular uptake behavior of M6P-GP and the corresponding mannose-GP polymer reveals that incorporation of the phosphate moiety at the 6-position of mannose completely alters its trafficking behavior and becomes exclusively lysosome specific. We also demonstrate that trafficking of M6P-GPs in mammalian cells is likely associated with the CI-MPR receptor pathway.</p>1 aDas, Soumen1 aParekh, Nimisha1 aMondal, Basudeb1 aGupta, Sayam, Sen  uhttps://library.ncl.res.in/content/controlled-synthesis-end-functionalized-mannose-6-phosphate-glycopolypeptides-lysosome02667nas a2200265   4500008004100000245013600041210006900177260000800246300001100254490000800265520177000273100001702043700001902060700002002079700002102099700001202120700001602132700001702148700002002165700003002185700002002215700002002235700001702255856012902272       2022                        eng d00aCopper(II) import and reduction are dependent on His-Met clusters in the extracellular amino terminus of human copper transporter-10 aCopperII import and reduction are dependent on HisMet clusters i  cMAR  a1016310 v2983 a<p>
	Copper(I) is an essential metal for all life forms. Though Cu(II) is the most abundant and stable state, its reduction to Cu(I) via an unclear mechanism is prerequisite for its bioutilization. In eukaryotes, the copper transporter-1(CTR1) is the primary high-affinity copper importer, although its mechanism and role in Cu(II) reduction remain uncharacterized. Here we show that extracellular amino-terminus of human CTR1 contains two methionine-histidine clusters and neighboring aspartates that distinctly bind Cu(I) and Cu(II) preceding its import. We determined that hCTR1 localizes at the basolateral membrane of polarized MDCK-II cells and that its endocytosis to Common-Recycling-Endosomes is regulated by reduction of Cu(II) to Cu(I) and subsequent Cu(I) coordination by the methionine cluster. We demonstrate the transient binding of both Cu(II) and Cu(I) during the reduction process is facilitated by aspartates that also act as another crucial determinant of hCTR1 endocytosis. Mutating the first Methionine cluster ((7)Met-Gly-Met(9)) and Asp(13)( )abrogated copper uptake and endocytosis upon copper treatment. This phenotype could be reverted by treating the cells with reduced and nonreoxidizable Cu(I). We show that histidine clusters, on other hand, bind Cu(II) and are crucial for hCTR1 functioning at limiting copper. Finally, we show that two N-terminal His-Met-Asp clusters exhibit functional complementarity, as the second cluster is sufficient to preserve copper-induced CTR1 endocytosis upon complete deletion of the first cluster. We propose a novel and detailed mechanism by which the two His-Met-Asp residues of hCTR1 amino-terminus not only bind copper, but also maintain its reduced state, crucial for intracellular uptake.</p>
1 aKar, Sumanta1 aSen, Samarpita1 aMaji, Saptarshi1 aSaraf, Deepashri1 aRuturaj1 aPaul, Rupam1 aDutt, Sohini1 aMondal, Basudeb1 aRodriguez-Boulan, Enrique1 aSchreiner, Ryan1 aSengupta, Durba1 aGupta, Arnab  uhttps://library.ncl.res.in/content/copperii-import-and-reduction-are-dependent-his-met-clusters-extracellular-amino-terminus