417-P: Functional Characterization of a Rare, Pathogenic Missense Variant Implicates FRAS1 as a Novel Gene for Risk of Progression to End-Stage Kidney Disease in Diabetes

作者：TIEHUA CHEN, Matthew B. Neeley, José M. Lázaro-Guevara, Melissa H. Pezzolesi, Christopher A. Simeone, Aylin R. Rodan, William L. Holland, Marcus G. Pezzolesi · 发表于：Diabetes · 年份：2023 · DOI：10.2337/db23-417-p · 研究领域：Genomics and Rare Diseases、Renal Diseases and Glomerulopathies、Chronic Kidney Disease and Diabetes

Progressive renal decline is the central manifestation of diabetic nephropathy (DN) that ultimately leads to end-stage kidney disease (ESKD). Leveraging an innovative family-based approach that integrates electronic medical record data, a unique population-based genealogy resource, and next-generation sequencing, we recently identified a rare missense variant (p.R2516C, allele frequency=0.00002) in FRAS1, which encodes an extracellular matrix protein that regulates epidermal basement membrane adhesion and mediates glomerular integrity, in a family with diabetes and ESKD. While this rare missense variant is predicted to be deleterious (CADD score=32), whether this impacts FRAS1 function is unknown; here, we set out to assess the functional impact of this variant. To do so, we used CRISPR-Cas9 gene editing technology to generate 3 novel HEK293 cell lines (2 FRAS1 knock-in cell lines (a synonymous p.H2520H control cell line and a missense p.R2516C variant cell line) and a FRAS1 knock-out cell line) and performed in vitro cell migration and cell adhesion assays. Relative to the control cell line, both the FRAS1 knock-out cell line and the missense variant cell line displayed significantly inhibited cell migration (p = 1.54X10-13 and p = 5.05X10-5, respectively). Similarly, cell adhesion was significantly inhibited in cells in which FRAS1 was knocked out and in those carrying the p.R2516C variant compared to the control cell line (p = 6.72X10-9 and p = 6.63X10-6, respectively). To...