Pawlowski Wojciech P, Golubovskaya Inna N, Timofejeva Ljudmilla, Meeley Robert B, Sheridan William F, Cande W Zacheus
Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA.
Science. 2004 Jan 2;303(5654):89-92. doi: 10.1126/science.1091110.
Pairing, synapsis, and recombination are prerequisites for accurate chromosome segregation in meiosis. The phs1 gene in maize is required for pairing to occur between homologous chromosomes. In the phs1 mutant, homologous chromosome synapsis is completely replaced by synapsis between nonhomologous partners. The phs1 gene is also required for installation of the meiotic recombination machinery on chromosomes, as the mutant almost completely lacks chromosomal foci of the recombination protein RAD51. Thus, in the phs1 mutant, synapsis is uncoupled from recombination and pairing. The protein encoded by the phs1 gene likely acts in a multistep process to coordinate pairing, recombination, and synapsis.
配对、联会和重组是减数分裂中染色体精确分离的先决条件。玉米中的phs1基因是同源染色体之间发生配对所必需的。在phs1突变体中，同源染色体联会完全被非同源配对之间的联会所取代。phs1基因对于减数分裂重组机制在染色体上的建立也是必需的，因为该突变体几乎完全缺乏重组蛋白RAD51的染色体位点。因此，在phs1突变体中，联会与重组和配对解偶联。phs1基因编码的蛋白质可能在一个多步骤过程中发挥作用，以协调配对、重组和联会。
