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Pleiotropic ZIP8 A391T implicates abnormal manganese homeostasis in complex human disease.

ABSTRACT: ZIP8 is a metal transporter with a role in manganese (Mn) homeostasis. A common genetic variant in ZIP8 (rs13107325; A391T) ranks in the top 10 of pleiotropic SNPs identified in GWAS; A391T has associations with an increased risk of schizophrenia, obesity, Crohn's disease, and reduced blood Mn. Here, we used CRISPR/Cas9-mediated knockin (KI) to generate a mouse model of ZIP8 A391T (Zip8 393T-KI mice). Recapitulating the SNP association with blood Mn, blood Mn was reduced in Zip8 393T-KI mice. There was restricted abnormal tissue Mn homeostasis, with decreases in liver and kidney Mn and a reciprocal increase in biliary Mn, providing in vivo evidence of hypomorphic Zip8 function. Upon challenge in a chemically induced colitis model, male Zip8 393T-KI mice exhibited enhanced disease susceptibility. ZIP8 391-Thr associated with reduced triantennary plasma N-glycan species in a population-based cohort to define a genotype-specific glycophenotype hypothesized to be linked to Mn-dependent glycosyltransferase activity. This glycophenotype was maintained in a cohort of patients with Crohn's disease. These data and the pleiotropic disease associations with ZIP8 391-Thr suggest underappreciated roles of Mn homeostasis in complex human disease.

SUBMITTER: Sunuwar L

PROVIDER: S-EPMC7605523 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Pleiotropic ZIP8 A391T implicates abnormal manganese homeostasis in complex human disease.

Sunuwar Laxmi L Frkatović Azra A Sharapov Sodbo S Wang Qinchuan Q Neu Heather M HM Wu Xinqun X Haritunians Talin T Wan Fengyi F Michel Sarah S Wu Shaoguang S Donowitz Mark M McGovern Dermot D Lauc Gordan G Sears Cynthia C Melia Joanna J

JCI insight 20201015 20

ZIP8 is a metal transporter with a role in manganese (Mn) homeostasis. A common genetic variant in ZIP8 (rs13107325; A391T) ranks in the top 10 of pleiotropic SNPs identified in GWAS; A391T has associations with an increased risk of schizophrenia, obesity, Crohn's disease, and reduced blood Mn. Here, we used CRISPR/Cas9-mediated knockin (KI) to generate a mouse model of ZIP8 A391T (Zip8 393T-KI mice). Recapitulating the SNP association with blood Mn, blood Mn was reduced in Zip8 393T-KI mice. Th ...[more]

PMID: 32897876

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Dataset Information

Pleiotropic ZIP8 A391T implicates abnormal manganese homeostasis in complex human disease.

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Pleiotropic ZIP8 A391T implicates abnormal manganese homeostasis in complex human disease.

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