Two genes required for meiotic recombination in Drosophila are expressed from a dicistronic message.
We have isolated two alleles of a previously unidentified meiotic recombination gene, mei-217. Genetic analysis of these mutants shows that mei-217 is a typical "precondition" gene. The phenotypes of the mutants are meiosis specific. The strongest allele has <10% of the normal level of crossing over, and the residual events are distributed abnormally. We have used double mutant analysis to position mei-217 in the meiotic recombination pathway. In general, mutations causing defects in the initiation of meiotic recombination are epistatic to mutations in mei-41 and spnB. These two mutations, however, are epistatic to mei-217, suggesting that recombination is initiated normally in mei-217 mutants. It is likely that mei-217 mutants are able to make Holliday junction intermediates but are defective in the production of crossovers. These phenotypes are most similar to mutants of the mei-218 gene. This is striking because mei-217 and mei-218 are part of the same transcription unit and are most likely produced from a dicistronic message.
Liu
H
H
Waksman Institute and Department of Genetics, Rutgers University, Piscataway, New Jersey 08854-8020, USA.
Jang
J K
JK
Graham
J
J
Nycz
K
K
McKim
K S
KS
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D018797:Cell Cycle Proteins / Q000235:genetics*; D003434:Crossing Over, Genetic; D018076:DNA, Complementary; D004330:Drosophila / Q000235:genetics*; D029721:Drosophila Proteins; D008040:Genetic Linkage; D008540:Meiosis / Q000235:genetics*; D008969:Molecular Sequence Data; D010641:Phenotype; D011995:Recombination, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic; D014960:X Chromosome
D018797:Cell Cycle Proteins; D018076:DNA, Complementary; D029721:Drosophila Proteins; C103176:mei-218 protein, Drosophila