Kidney Week

Abstract: FR-PO1005

GAS2L2 as a Candidate Gene for Nephrotic Syndrome

Session Information

• Genetic Diseases of the Kidneys: Non-Cystic - II
  October 26, 2018 | Location: Exhibit Hall, San Diego Convention Center
  Abstract Time: 10:00 AM - 12:00 PM

Category: Genetic Diseases of the Kidney

• 1002 Genetic Diseases of the Kidney: Non-Cystic

Authors

• Widmeier, Eugen, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts, United States

Eugen Widmeier,

• Hugo, Hannah, Boston Children's Hospital, Boston, Massachusetts, United States

Hannah Hugo,

• Shril, Shirlee, Boston Childrens Hospital, Boston, Massachusetts, United States

Shirlee Shril,

• Hildebrandt, Friedhelm, Boston Children's Hospital, Boston, Massachusetts, United States

Friedhelm Hildebrandt,

Background

Steroid resistant nephrotic syndrome (SRNS) inevitably progresses to end-stage renal disease (ESRD) within the first three decades of life requiring dialysis or transplantation for survival. To date discovery of more than 50 different monogenic causes of SRNS has helped to elucidate the pathogenesis of SRNS.

Methods

To identify novel mongenic causes of NS, we performed whole exome sequencing, homozygosity mapping, and targeted exon sequencing. To investigate molecular mechanisms of a newly identified monogenic cause of NS in vitro, we generated immortalized human podocyte cell lines with stable knockdown of the GAS2L2 gene.

Results

By next-generation sequencing, we identified a homozygous recessive missense mutation in a region of high evolutionary conservation (Drosophila melanogaster) within the GAS2 domain of GAS2L2 gene (c.817C>T, p.Arg273Cys) in a patient with early onset NS. GAS2L2 is a known linker between actin filaments and microtubules. We show that GFP-GAS2L2 localizes to the cytoskeleton filaments and that knockdown of GAS2L2 results in severe defect of podocytes migration rate.

Conclusion

We discovered a recessive mutation of GAS2L2 as a likely novel monogenic cause of early-onset SRNS. We propose that the disease phenotype is caused by defect of crosstalk between actin filaments and microtubules.

Funding

• Other NIH Support