Genomic organization, expression analysis, and chromosomal localization ofthe mouse PEX3 gene encoding a peroxisomal assembly protein

The peroxin Pex3p has been identified as an integral peroxisomal membrane p rotein in yeast where pex3 mutants lack peroxisomal remnant structures. Alt hough not proven in higher organisms, a role of this gene in the early pero xisome biogenesis is suggested, We report here the cDNA cloning and the gen omic structure of the mouse PEX3 gene. The 2 kb cDNA encodes a polypeptide of 372 amino acids (42 kDa). The gene spans a region of 30 kb, contains 12 exons and 11 introns and is located on band A of chromosome 10, The putativ e promoter region exhibits characteristic housekeeping features. PEX3 expre ssion was identified in all tissues analyzed, with the strongest signals in liver and in testis, and could not be induced by fenofibrate. The data pre sented may be useful for the generation of a mouse model defective in PEX3 in order to clarify the yet unknown functional impact of disturbances in ea rly peroxisomal membrane assembly.