Sexual mating of Botrytis cinerea illustrates PRP8 intein HEG activity

• Published in: Fungal genetics and biology 2010-04, Vol.47 (4), p.392-398
• Main Authors: Bokor, Annika A.M., van Kan, Jan A.L., Poulter, Russell T.M.
• Format: Article
• Language: English
• Subjects: Botrytis - enzymology; Botrytis - growth & development; Botrytis cinerea; branched intermediate; DNA, Fungal - metabolism; endodeoxyribonucleases; endonuclease; Endonucleases - metabolism; Evolution; Fungal Proteins - metabolism; Gene Conversion; genes; Homing; Homing endonuclease; Horizontal transfer; Intein; Inteins; Meiosis; populations; Prp8; Prp8 gene; saccharomyces-cerevisiae; selfish gene; sexual reproduction; Splicing
• ISSN: 1087-1845; 1096-0937
• DOI: 10.1016/j.fgb.2010.01.003

Strains of Botrytis cinerea are polymorphic for the presence of an intein in the Prp8 gene (intein +/−). The intein encodes a homing endonuclease (HEG). During meiosis in an intein +/− heterozygote, the homing endonuclease initiates intein ‘homing’ by inducing gene conversion. In such meioses, the homing endonuclease triggers gene conversion of the intein together with its flanking sequences into the empty allele. The efficiency of gene conversion of the intein was found to be 100%. The extent of flanking sequence affected by the gene conversion varied in different meioses. A survey of the inteins and flanking sequences of a group B. cinerea isolates indicates that there are two distinct variants of the intein both of which have active HEGs. The survey also suggests that the intein has been actively homing during the evolution of the species and that the PRP8 intein may have entered the species by horizontal transfer.