A Meiotic Drive Element in the Maize Pathogen Fusarium verticillioides Is Located Within a 102 kb Region of Chromosome V.
Fusarium verticillioides is an agriculturally important fungus because of its association with maize and its propensity to contaminate grain with toxic compounds. Some isolates of the fungus harbor a meiotic drive element known as Spore killer (Sk(K)) that causes nearly all surviving meiotic progeny from an Sk(K) × Spore killer-susceptible (Sk(S)) cross to inherit the Sk(K) allele. Sk(K) has been mapped to chromosome V but the genetic element responsible for meiotic drive has yet to be identified. In this study, we used cleaved amplified polymorphic sequence markers to genotype individual progeny from an Sk(K) × Sk(S) mapping population. We also sequenced the genomes of three progeny from the mapping population to determine their single nucleotide polymorphisms. These techniques allowed us to refine the location of Sk(K) to a contiguous 102 kb interval of chromosome V, herein referred to as the Sk region. Relative to Sk(S) genotypes, Sk(K) genotypes have one extra gene within this region for a total of 42 genes. The additional gene in Sk(K) genotypes, herein named SKC1 for Spore Killer Candidate 1, is the most highly expressed gene from the Sk region during early stages of sexual development. The Sk region also has three hyper-variable regions, the longest of which includes SKC1 The possibility that SKC1, or another gene from the Sk region, is an essential component of meiotic drive and spore killing is discussed.
School of Biological Sciences, Illinois State University, Normal, Illinois 61790.
Jay
J
Pyle
School of Biological Sciences, Illinois State University, Normal, Illinois 61790.
Tejas
T
Patel
School of Biological Sciences, Illinois State University, Normal, Illinois 61790.
Brianna
B
Merrill
School of Biological Sciences, Illinois State University, Normal, Illinois 61790.
Chabu
C
Nsokoshi
School of Biological Sciences, Illinois State University, Normal, Illinois 61790.
Morgan
M
McCall
Mycotoxin Prevention and Applied Microbiology, National Center for Agricultural Utilization Research, U.S. Department of Agriculture, Agricultural Research Service, Peoria, Illinois 61604.
Robert H
RH
Proctor
Mycotoxin Prevention and Applied Microbiology, National Center for Agricultural Utilization Research, U.S. Department of Agriculture, Agricultural Research Service, Peoria, Illinois 61604 daren.brown@ars.usda.gov tmhammo@ilstu.edu.
Daren W
DW
Brown
School of Biological Sciences, Illinois State University, Normal, Illinois 61790 daren.brown@ars.usda.gov tmhammo@ilstu.edu.
Thomas M
TM
Hammond
D015825:Chromosomes, Fungal; D003433:Crosses, Genetic; D005656:Fungal Proteins / Q000235:genetics; D005670:Fusarium / Q000235:genetics* / Q000472:pathogenicity; D015966:Gene Expression Regulation, Fungal; D016681:Genome, Fungal; D008540:Meiosis; D012150:Polymorphism, Restriction Fragment Length; D020641:Polymorphism, Single Nucleotide; D013172:Spores, Fungal / Q000235:genetics; D003313:Zea mays / Q000382:microbiology*
D005656:Fungal Proteins
fungi; genomic conflict; mapping; meiotic drive; spore killing