is essential for zebrafish embryogenesis and pronephros formation.

BACKGROUND AND OBJECTIVES

Friedreich's Ataxia (FRDA) is a genetic disease that affects a variety of different tissues. The disease is caused by a mutation in the gene ( which is important for the synthesis of iron-sulfur clusters. The primary pathologies of FRDA are loss of motor control and cardiomyopathy. These occur due to the accumulation of reactive oxygen species (ROS) in the brain and the heart due to their high metabolic rates. Our research aims to understand how developmental processes and the kidney are impacted by a deficiency of .

METHODS

We utilized an antisense oligomer, or morpholino, to knockdown the gene () in zebrafish embryos. Knockdown was confirmed via RT-PCR, gel electrophoresis, and Sanger sequencing. To investigate phenotypes, we utilized several staining techniques including whole mount hybridization, Alcian blue, and acridine orange, as well as dextran-FITC clearance assays.

RESULTS

deficient animals displayed otolith malformations, edema, and reduced survival. Alcian blue staining revealed craniofacial defects in deficient animals, and gene expression studies showed that the pronephros, or embryonic kidney, had several morphological defects. We investigated the function of the pronephros through clearance assays and found that the renal function is disrupted in deficient animals in addition to proximal tubule endocytosis. Utilizing acridine orange staining, we found that cell death is a partial contributor to these phenotypes.

DISCUSSION AND CONCLUSION

This work provides new insights about how deficiency impacts development and kidney morphogenesis. Additionally, this work establishes an additional model system to study FRDA.