Location: Toxicology & Mycotoxin ResearchTitle: Generation of a Fusarium verticillioides 7600 near isogenic Mat1-2 line for multi-mutant generation.
|VO, VIVIAN - University Of Georgia|
|WILLIAMS, FELICIA - Duke University|
|Glenn, Anthony - Tony|
Submitted to: American Phytopathological Society
Publication Type: Abstract Only
Publication Acceptance Date: 4/15/2021
Publication Date: N/A
Technical Abstract: Fungal genetic systems ideally combine molecular tools for genome manipulation with a sexual reproduction system for informative assortment of combinations of genomic modifications. Critical molecular tools include efficient transformation and capacity for homologous integration, while the assortment approach requires a heterothallic sexual cycle. When employing the sexual cycle to generate multi-mutants, the background genotype variation of the parents may impact phenotypic variation amongst progeny. Here, to mitigate this variation, we generated a Mat1-2 strain that is near isogenic to the sequenced Mat1-1 Fusarium verticillioides wild type, FGSC7600. This was accomplished by crossing FGSC7600 as a male to the divergent wild-type strain FGSC7603 as female; followed by six generations of Mat1-2 progeny backcrosses to the FGSC7600 male. We sequenced each generation and mapped recombination. The first 3 crosses generated progeny with near predicted contributor genome content. The parental cross involved 26 crossovers on 9 of the 11 chromosomes, and the F1 had 54% (50% predicted) non-recurrent parent SNP genotype. Cross 2 and 3 progenies had 32% and 12%, (25% and 12.5 % predicted), respectively. Inheritance of complete chromosomes without crossover was frequently observed. The final product strain (10/35, Mat1-2) retained 7% of the original Mat1-2 parent SNP genotype and thus is about 93% identical to FGSC7600. This is below expected, but still should theoretically yield final double mutants containing about 98% FGSC7600 compared to 75% by our standard two-cross method.