Pex19p interacts with Pex3p and Pex10p and is essential for peroxisome biogenesis in Pichia pastorisSnyder, WB., Faber, KN., Wenzel, TJ., Koller, A., Luers, GH., Rangell, L., Keller, GA. & Subramani, S., Jun-1999, In : Molecular Biology of the Cell. 10, 6, p. 1745-1761 17 p.
Research output: Contribution to journal › Article › Academic › peer-review
We report the cloning and characterization of Pichia pastoris PEX19 by complementation of a peroxisome-deficient mutant strain. Import of peroxisomal targeting signal 1- and 2-containing peroxisomal matrix proteins is defective in pex19 mutants. PEX19 encodes a hydrophilic 299-amino acid protein with sequence similarity to Saccharomyces cerevisiae Pex19p and human and Chinese hamster PxF, all farnesylated proteins, as well as hypothetical proteins from Caenorhabditis elegans and Schizosaccharomyces pombe. The farnesylation consensus is conserved in PpPex19p but dispensable for function and appears unmodified under the conditions tested. Pex19p localizes predominantly to the cytosolic fraction. Biochemical and two-hybrid analyses confirmed that Pex19p interacts with Pex3p, as seen in S, cerevisiae, but unexpectedly also with Pex10p. Two-hybrid analysis demonstrated that the amino-terminal 42 amino acids of Pex19p interact with the carboxyl-terminal 335 amino acids of Pex3p. In addition, the extreme carboxyl terminus of Pex19p (67 amino acids) is required for interaction with the amino-terminal 380 amino acids of Pex10p. Biochemical and immunofluorescence microscopy analyses of pex19 Delta cells identified the membrane protein Pex3p in peroxisome remnants that were not previously observed in S. cerevisiae. These small vesicular and tubular (early) remnants are morphologically distinct from other Pppex mutant (late) remnants, suggesting that Pex19p functions at an early stage of peroxisome biogenesis.
|Number of pages||17|
|Journal||Molecular Biology of the Cell|
|Publication status||Published - Jun-1999|
- INTEGRAL MEMBRANE-PROTEIN, RAT-LIVER PEROXISOMES, SACCHAROMYCES-CEREVISIAE, TARGETING SIGNAL, 3-KETOACYL-COA THIOLASE, HANSENULA-POLYMORPHA, FARNESYLATED PROTEIN, PTS1 RECEPTOR, GENE, IMPORT