A Hereditary Enteropathy Caused by Mutations in the SLCO2A1 Gene, Encoding a Prostaglandin Transporter

作者:Umeno Junji*; Hisamatsu Tadakazu; Esaki Motohiro; Hirano Atsushi; Kubokura Naoya; Asano Kouichi; Kochi Shuji; Yanai Shunichi; Fuyuno Yuta; Shimamura Katsuyoshi; Hosoe Naoki; Ogata Haruhiko; Watanabe Takashi; Aoyagi Kunihiko; Ooi Hidehisa; Watanabe Kenji; Yasukawa Shigeyoshi; Hirai Fumihito; Matsui Toshiyuki; Iida Mitsuo; Yao Tsuneyoshi; Hibi Toshifumi; Kosaki Kenjiro; Kanai Takanori; Kitazono Takanari; Matsumoto Takayuki
来源:PLoS Genetics, 2015, 11(11): e1005581.
DOI:10.1371/journal.pgen.1005581

摘要

Previously, we proposed a rare autosomal recessive inherited enteropathy characterized by persistent blood and protein loss from the small intestine as chronic nonspecific multiple ulcers of the small intestine (CNSU). By whole-exome sequencing in five Japanese patients with CNSU and one unaffected individual, we found four candidate mutations in the SLCO2A1 gene, encoding a prostaglandin transporter. The pathogenicity of the mutations was supported by segregation analysis and genotyping data in controls. By Sanger sequencing of the coding regions, 11 of 12 other CNSU patients and 2 of 603 patients with a diagnosis of Crohn's disease were found to have homozygous or compound heterozygous SLCO2A1 mutations. In total, we identified recessive SLCO2A1 mutations located at seven sites. Using RT-PCR, we demonstrated that the identified splice-site mutations altered the RNA splicing, and introduced a premature stop codon. Tracer prostaglandin E2 uptake analysis showed that the mutant SLCO2A1 protein for each mutation exhibited impaired prostaglandin transport. Immunohistochemistry and immunofluorescence analyses revealed that SLCO2A1 protein was expressed on the cellular membrane of vascular endothelial cells in the small intestinal mucosa in control subjects, but was not detected in affected individuals. These findings indicate that loss-of-function mutations in the SLCO2A1 gene encoding a prostaglandin transporter cause the hereditary enteropathy CNSU. We suggest a more appropriate nomenclature of "chronic enteropathy associated with SLCO2A1 gene" (CEAS).

  • 出版日期2015-11