M.S. / Molecular Biology / This thesis describes the cloning and analysis of PER6, a gene required for peroxisome biogenesis in Pichia pastoris. The gene was cloned by functional complementation of a per6 P. pastoris mutant strain that was one of a number of peroxisome-deficient mutants isolated in this laboratory. The complementing activity was localized to a small DNA fragment by subcloning and Northern filter hybridization analysis and the DNA sequence of the fragment was determined. The sequence revealed a 1296-bp open reading frame which potentially encodes a 432-amino acid protein of 49 kD. The gene was transcribed into a message of 1.4 kilobases that was constitutively expressed but induced several-fold in cells growing on methanol. A mutant strain with a deletion of a large portion of the open reading frame was constructed and used to genetically demonstrate that the cloned gene was identical to the defective gene in the originally isolated per6 mutant. The predicted amino acid sequence of the PER6 product revealed several interesting features, including a significant regional similarity to PAF-1, a gene known to be defective in some patients with Zellweger syndrome, a lethal human genetic disease caused by peroxisome deficiency. Finally, the PER6 product was produced in E. coli and purified to serve as antigen for antibody production.

Thesis (M.S.), Oregon Graduate Institute of Science & Technology, 1993.