A global Slc7a7 knockout mouse model demonstrates characteristic phenotypes of human lysinuric protein intolerance
Year: 2020
Type: article
Abstract: Lysinuric protein intolerance (LPI) is an inborn error of cationic amino acid (arginine, lysine, ornithine) transport caused by biallelic pathogenic variants in SLC7A7, which encodes the light subunit of the y+LAT1 transporter. Treatments for the complications of LPI, including growth failure, renal disease, pulmonary alveolar proteinosis, autoimmune disorders and osteoporosis, are limited. Given the early lethality of the only published global Slc7a7 knockout mouse model, a viable animal model to investigate global SLC7A7 deficiency is needed. Hence, we generated two mouse models with global Slc7a7 deficiency (Slc7a7em1Lbu/em1Lbu; Slc7a7Lbu/Lbu and Slc7a7em1(IMPC)Bay/em1(IMPC)Bay; Slc7a7Bay/Bay) using CRISPR/Cas9 technology by introducing a deletion of exons 3 and 4. Perinatal lethality was observed in Slc7a7Lbu/Lbu and Slc7a7Bay/Bay mice on the C57BL/6 and C57BL/6NJ inbred genetic backgrounds, respectively. We noted improved survival of Slc7a7Lbu/Lbu mice on the 129 Sv/Ev × C57BL/6 F2 background, but postnatal growth failure occurred. Consistent with human LPI, these Slc7a7Lbu/Lbu mice exhibited reduced plasma and increased urinary concentrations of the cationic amino acids. Histopathological assessment revealed loss of brush border and lipid vacuolation in the renal cortex of Slc7a7Lbu/Lbu mice, which combined with aminoaciduria suggests proximal tubular dysfunction. Micro-computed tomography of L4 vertebrae and skeletal radiographs showed delayed skeletal development and suggested decreased mineralization in Slc7a7Lbu/Lbu mice, respectively. In addition to delayed skeletal development and delayed development in the kidneys, the lungs and liver were observed based on histopathological assessment. Overall, our Slc7a7Lbu/Lbu mouse model on the F2 mixed background recapitulates multiple human LPI phenotypes and may be useful for future studies of LPI pathology.
Source: Human Molecular Genetics
DOI: 10.1093/hmg/ddaa107
Authors: Bridget M Stroup, Ronit Marom, Xiaohui Li, Chih-Wei Hsu, Cheng-Yen Chang, Luan D Truong, Brian Dawson, Ingo Grafe, Yuqing Chen, Ming-Ming Jiang, Denise Lanza, Jennie Rose Green, Qin Sun, J P Barrish, Safa Ani, Audrey E Christiansen, John R Seavitt, Mary E Dickinson, Farrah Kheradmand, Jason D Heaney, Brendan Lee, Lindsay C Burrage
Language: English
Subfield: Biochemistry
Domain: Life Sciences
Open Access status: bronze
Funders: Cancer Prevention and Research Institute of Texas, John S. Dunn Gulf Coast Consortium for Chemical Genomics, National Institutes of Health, U.S. Public Health Service, Intellectual and Developmental Disabilities Research Center, National Cancer Institute, National Institute of General Medical Sciences, National Institute of Diabetes and Digestive and Kidney Diseases, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institute of Dental and Craniofacial Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development
Awards: G1117550146, G1147702603, G1289049516, G1310211398, G2408463728, G2609925829, Nitric Oxide and Bone Homeostasis in Patients with Argininosuccinate Lyase Deficiency, G274084553, G2843249294, The Combinatorial Drug Discovery Program (CDDP), G4819929959, G5275720599, G5313339769, G549442608, RESEARCH TRAINING IN PEDIATRIC GASTROENTEROLOGY, G7189771219, G720601659, GCC Center for Advanced Microscopy and Image Informatics, G7837447426, G8413015676, Baylor College of Medicine Comprehensive Cancer Training Program, G8733582291, G9000013585, G9000045078, G9000200400, G9000213352, G9000240210, G9000255214, G9000293998, G9000335951, Medical Genetics Research Fellowship Program, Baylor College of Medicine Cancer Center - Cancer Center Support Grant
OpenAlex ID: W3033654752