Meiotic recombination-related DNA synthesis and its implications for cross-over and non-cross-over recombinant formation.
Meiotic recombination-related DNA synthesis (MRDS) was analyzed in Saccharomyces cerevisiae by specifically timed incorporation of thymidine analogs into chromosomes. Lengths and positions of incorporation tracts were determined relative to a known recombination hot spot along DNA, as was the timing and localization of incorporation relative to forming and formed synaptonemal complex in spread chromosomes. Distinct patterns could be specifically associated with the majority cross-over and non-cross-over recombination processes. The results obtained provide direct evidence for key aspects of current consensus recombination models, provide information regarding temporal and spatial relationships between non-cross-over formation and the synaptonemal complex, and raise the possibility that removal of RecA homolog Rad51 plays a key role in regulating onset of MRDS. Finally, classical observations on MRDS in Drosophila, mouse, and lily are readily mapped onto the findings presented here, providing further evidence for a broadly conserved meiotic recombination process.
Terasawa
Masahiro
M
Iwate College of Nursing, Ohgama, Takizawa, Iwate 020-0151, Japan.
Ogawa
Hideyuki
H
Tsukamoto
Yasumasa
Y
Shinohara
Miki
M
Shirahige
Katsuhiko
K
Kleckner
Nancy
N
Ogawa
Tomoko
T
D000818:Animals; D015825:Chromosomes, Fungal / Q000235:genetics / Q000378:metabolism; D003434:Crossing Over, Genetic; D004261:DNA Replication; D004271:DNA, Fungal / Q000235:genetics / Q000378:metabolism; D004330:Drosophila / Q000235:genetics; D008540:Meiosis; D051379:Mice; D008957:Models, Genetic; D051135:Rad51 Recombinase / Q000235:genetics; D011938:Rec A Recombinases / Q000235:genetics; D011995:Recombination, Genetic; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics; D013573:Synaptonemal Complex / Q000235:genetics
D004271:DNA, Fungal; D029701:Saccharomyces cerevisiae Proteins; C495151:RAD51 protein, S cerevisiae; D051135:Rad51 Recombinase; D011938:Rec A Recombinases