Sequence requirements for splicing by the Cne PRP8 intein.
The dependence of protein splicing on conserved residues of the Cne PRP8 intein was assessed by alanine scanning mutagenesis in a foreign protein context. Corroboration was obtained for the involvement of residues at the splice junctions and of the conserved threonine and histidine of motif B. Five additional residues were identified as absolutely required for splicing. Variant W151A displayed premature C-terminal cleavage, not seen with other Cne PRP8 mutants. We propose a model whereby W151 acts to prevent premature C-terminal cleavage, favoring complete splicing as opposed to two disjointed cleavage events.
Pearl
Esther J
EJ
Department of Biochemistry, University of Otago, Dunedin 9054, New Zealand.
Tyndall
Joel D A
JD
Poulter
Russell T M
RT
Wilbanks
Sigurd M
SM
D000595:Amino Acid Sequence; D016384:Consensus Sequence; D003455:Cryptococcus neoformans / Q000378:metabolism; D047668:Inteins; D008958:Models, Molecular; D008969:Molecular Sequence Data; D050505:Mutant Proteins / Q000235:genetics / Q000378:metabolism; D019154:Protein Splicing; D012323:RNA Processing, Post-Transcriptional; D016601:RNA-Binding Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D017381:Spliceosomes / Q000737:chemistry / Q000378:metabolism
D050505:Mutant Proteins; D016601:RNA-Binding Proteins