Chronic kidney disease

Mechanisms of APOL1-associated renal disease

Credit: Jennie Vallis/NPG

Mutations in APOL1 are associated with an increased risk of renal disease and are found at a high frequency in people of African ancestry. Two recent studies used transgenic Drosophila melanogaster models to investigate the molecular mechanisms that underlie APOL1-associated renal disease.

Karl Skorecki and colleagues showed that expression of APOL1-G1 or G2 risk variants in Drosophila nephrocytes — which are homologous to human podocytes — resulted in the accumulation of an endocytic tracer, followed by nephrocyte loss in older flies. Further investigations in Saccharomyces cerevisiae provided evidence that APOL1 risk alleles impair endosomal trafficking and vacuole acidification.

Similarly, Zhe Han and colleagues found that nephrocyte-specific expression of APOL1 or APOL1-G1 in Drosophila resulted in increased endocytic activity and reduced organelle acidification, followed by a loss of function, increase in size and premature death of nephrocytes as the flies aged. The phenotype was most severe in flies that expressed APOL1-G1 and was similar to that of cultured mammalian podocytes that overexpress this risk allele.

APOL1 risk alleles impair endosomal trafficking and vacuole acidification”

“To observe fly renal cell dysfunction as a result of expressing APOL1 in nephrocytes, and to be able to relate the resulting phenotypes to APOL1-associated pathology of human podocytes, is a major advance for the use of Drosophila as a biomedical model with clinical relevance,” says Han. “The findings also tell us some very important things about APOL1 protein function. I am confident that genetic screening in Drosophila will unveil interaction networks of proteins and pathways with APOL1 that will significantly advance our understanding of the mechanisms by which APOL1 causes kidney disease.”

References

  1. 1

    Fu, Y. et al. APOL1-G1 in nephrocytes induces hypertrophy and accelerates cell death. J. Am. Soc. Nephrol. http://dx.doi.org/10.1681/ASN.2016050550 (2016)

  2. 2

    Kruzel-Davila, E. et al. APOL1-mediated cell injury involves disruption of conserved trafficking processes. J. Am. Soc. Nephrol. http://dx.doi.org/10.1681/ASN.2016050546 (2016)

Download references

Authors

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Carney, E. Mechanisms of APOL1-associated renal disease. Nat Rev Nephrol 13, 62 (2017). https://doi.org/10.1038/nrneph.2016.175

Download citation

Further reading

Search

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing