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From expressed sequence tags to peroxisome biogenesis disorder genes
1Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.
Annals of the New York Academy of Sciences
|December 27, 1996
Summary
Identifying human peroxisome biogenesis disorder genes is now feasible using computer-based homology probing. This method successfully identified PXR1, a gene linked to peroxisome disorders, highlighting yeast as a valuable model.
Area of Science:
- Genetics
- Molecular Biology
- Cell Biology
Background:
- Isolation of human disease genes is challenging, often requiring labor-intensive positional cloning.
- Peroxisome biogenesis disorders (PBDs) represent a group of genetic diseases affecting peroxisome function.
- Functional complementation and computer-based homology probing are alternative strategies for PBD gene discovery.
Purpose of the Study:
- To explore computer-based homology probing as a strategy for identifying human peroxisome biogenesis disorder genes.
- To validate the utility of yeast peroxisome assembly (PAS) genes as models for human PBD gene discovery.
- To identify novel candidate genes for PBDs by screening expressed sequence tag (EST) databases.
Main Methods:
- Utilized computer-based homology probing by screening the dbEST database for human genes with sequence similarity to known yeast PAS genes.
- Applied functional complementation assays to validate candidate genes.
- Performed detailed genetic analysis to confirm mutations in identified genes as the cause of PBDs.
Main Results:
- Successfully identified PXR1 as the human orthologue of the Pichia pastoris PAS8 gene.
- Identified PXAAA1 as a human homologue of the Pichia pastoris PAS5 gene.
- Demonstrated that mutations in PXR1 are responsible for complementation group 2 of the peroxisome biogenesis disorders.
Conclusions:
- Computer-based homology probing is an effective strategy for isolating human PBD genes.
- Human homologues of yeast PAS genes exist and are implicated in PBDs.
- Yeast PAS mutants serve as accurate and valuable models for studying human peroxisome biogenesis disorders.
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