Friday, June 18, 2010

Crispy Hot Peroxisome Papers.. Fresh from the oven of science.

Peroxisomes in zebrafish: distribution pattern and knockdown studies

Histochem Cell Biol. 2010 Jun 17. [Epub ahead of print]
by the group of M. Baes at Katholieke Universiteit Leuven, Belgium

Abstract - (from Pubmed)
          Peroxisomes are organelles that are essential for normal development in men and mice. In order to explore whether zebrafish could be used as a model system to study the role of peroxisomes, we examined their distribution pattern in developing and adult zebrafish and we tested different approaches to eliminate them during the first days after fertilization. In 4-day-old embryos, catalase-containing peroxisomes were obvious in the liver, the pronephric duct and the wall of the yolk sac, but transcripts for peroxisomal matrix and membrane proteins were also detected in the head region from 24 h post-fertilization. In adult zebrafish, catalase-containing peroxisomes remained prominent in the hepatocytes, the renal proximal tubules and the intestinal epithelium. Several peroxins, essential proteins for the biogenesis of peroxisomes, were targeted using knockdown approaches. Two morpholinos, blocking, respectively, splice sites in pex3 and pex13, only induced a short in frame deletion or insertion in the transcripts and did not result in the elimination of peroxisomes after injection into one-cell embryos. A morpholino blocking translation of pex13 was able to reduce the number of peroxisomes to variable extents. Finally, overexpression of a potential dominant negative fragment of Pex3p did not result in deletion of peroxisomes from developing zebrafish. 
We conclude that in zebrafish 
(1) peroxisomes, as visualized by DAB cytochemistry for catalase activity, are most conspicuous in the liver and renal tubular epithelium; this pattern is reminiscent of peroxisome occurrence in mammalian organs
(2) our approaches to eliminate these organelles during development by targeting peroxins were not successful.

New Review accepted in Journal of Lipid Research (JLR)
Biochemistry and genetics of inherited disorders of peroxisomal fatty acid metabolism
Paul P. Van Veldhoven
K.U.Leuven, Belgium

No comments:

Post a Comment