Fish mesonephric model of polycystic kidney disease in medaka (Oryzias latipes) pc mutant.
BACKGROUND
Polycystic kidney disease (PKD) is a common hereditary disease. A number of murine and zebrafish mutants have been generated and used for the study of PKD as metanephric and pronephric models, respectively. Here, we report a medaka (Oryzias latipes) mutant that develops numerous cysts in the kidney in adulthood fish in an autosomal-recessive manner as a mesonephric model of PKD.


METHODS
The phenotypes of the medaka pc mutant were described in terms of morphologic, histologic, and ultrastructural features. The pc see-through stock was produced by crossing a pc mutant and a fish from the see-through stock and used for observing the kidney through the transparent body wall of a live fish.


RESULTS
The mutant developed bilateral massive enlargement of the kidney in adulthood. They sexually matured normally within 2 months of age and died within 6 months of age. The affected kidney was occupied by numerous, fluid-filled cysts, which were lined by attenuated squamous epithelial cells. Developmentally, cystic formation began in the pronephros in 10-day-old fry and in the mesonephros in 20-day-old fry at the microscopic level. The pc see-through stock was useful in observing disease progression in live fish.


CONCLUSIONS
The kidney disorder that develops in the medaka pc mutant is a mesonephric counterpart of PKD, particularly an autosomal-dominant PKD, based on its morphologic, histologic, and ultrastructural features, and slow progression.
Mochizuki
Emiko
E
Laboratory of Freshwater Fish Stocks, Bioscience and Biotechnology Center, Nagoya University, Nagoya, Japan.
Fukuta
Katsuhiro
K
Tada
Tatsuya
T
Harada
Tomohiro
T
Watanabe
Naoki
N
Matsuo
Seiichi
S
Hashimoto
Hisashi
H
Ozato
Kenjiro
K
Wakamatsu
Yuko
Y
D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D005799:Genes, Dominant; D007684:Kidney Tubules / Q000002:abnormalities / Q000473:pathology / Q000648:ultrastructure; D008297:Male; D008650:Mesonephros / Q000473:pathology* / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D009154:Mutation; D009399:Nephrons / Q000002:abnormalities / Q000473:pathology / Q000648:ultrastructure; D009929:Organ Size; D009990:Oryzias / Q000002:abnormalities / Q000235:genetics*; D010641:Phenotype; D007690:Polycystic Kidney Diseases / Q000235:genetics* / Q000473:pathology*