title: A nuclear-encoded intein in the fungal pathogen Cryptococcus neoformans.
abstract: We have used comparative sequence analysis to identify an intein-like sequence (protein splicing element) present in Cryptococcus neoformans, a fungal pathogen of humans. The sequence encoding this element is present in the C. neoformans PRP8 gene, as an in-frame insertion relative to the PRP8 genes of other organisms. It contains sequences similar to those of the protein-splicing domains of two previously described yeast inteins (in Saccharomyces cerevisiae and Candida tropicalis), although it lacks any recognizable internal endonuclease domain. The Cryptococcus neoformans intein (Cne PRP8) is only the second to be found in a eukaryote nuclear genome; the previously described yeast inteins occur at the same site in the VMA gene homologues of S. cerevisiae and C. tropicalis. The host gene of the Cryptococcus intein, PRP8, encodes a highly conserved mRNA splicing protein found as part of the spliceosome. The Cne PRP8 intein may be a useful drug target in addressing the cryptococcal infections so prevalent in AIDS patients.
authors.affiliation: Department of Biochemistry, University of Otago, Dunedin, New Zealand. margi@sanger.otago.ac.nz
authors.forename: M I
authors.initials: MI
authors.lastname: Butler
authors.forename: T J
authors.initials: TJ
authors.lastname: Goodwin
authors.forename: R T
authors.initials: RT
authors.lastname: Poulter
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003455:Cryptococcus neoformans / Q000235:genetics* / Q000378:metabolism; D004271:DNA, Fungal / Q000235:genetics* / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics*; D005800:Genes, Fungal; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D017414:Ribonucleoprotein, U4-U6 Small Nuclear; D017415:Ribonucleoprotein, U5 Small Nuclear; D029701:Saccharomyces cerevisiae Proteins; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
chemical_list: D004271:DNA, Fungal; D005656:Fungal Proteins; C077018:PRP8 protein, S cerevisiae; D017414:Ribonucleoprotein, U4-U6 Small Nuclear; D017415:Ribonucleoprotein, U5 Small Nuclear; D029701:Saccharomyces cerevisiae Proteins