Cloning of a cDNA from Arabidopsis thaliana homologous to the human XPB gene

摘要: Abstract The human gene XPB, defective in xeroderma pigmentosum patients complementation group B, encodes a DNA helicase involved several metabolic pathways, including repair and transcription. high conservation of this has allowed the cloning homologs various species, such as mouse, yeast Drosophila. Not much information on molecular basis nucleotide excision plants is available, but these organisms may have similar mechanisms to other eukaryotes. A homolog XPB was isolated Arabidopsis thaliana by using polymerase chain reaction (PCR) with degenerate oligonucleotides based protein domains which are conserved among species. Screening an cDNA library led identification isolation clone 2670 bp encoding predicted 767 amino acids, denoted araXPB. Genomic analysis indicated that nuclear single copy plant cells. Northern blot probe revealed major transcript migrated at approx. 2 800 b, agreement size isolated. araXPB shares approximately 50% identical 70% acids homologs. maintains all functional found proteins, localization signal, DNA-binding domain motifs, suggesting it might also act part RNA transcription apparatus, well