Sigrist S, Ried G, Lehner C F
Friedrich-Miescher-Laboratorium der Max-Planck-Gesellschaft, Tübingen, Germany.
Mech Dev. 1995 Oct;53(2):247-60. doi: 10.1016/0925-4773(95)00441-3.
We have analyzed the requirement for Drosophila cdc2 kinase during spermatogenesis after generating temperature-sensitive mutant lines (Dmcdc2ts) by re-constructing mutations known to result in temperature sensitivity in fission yeast cdc2+. While meiotic spindles and metaphase plates were never formed in Dmcdc2ts mutants at high temperature, chromosomes still condensed in late spermatocytes and spermatid differentiation (sperm head and tail formation) continued. The same phenotype was also observed in twine and twine, Dmcdc2ts double mutant testes, consistent with the idea that the cdc2 kinase activity required for meiotic divisions is activated by the Twine/cdc25 phosphatase. Confirming this notion, we find that ectopic expression of the String/cdc25 phosphatase, which is known to activate the cdc2 kinase before mitosis, results in a partial rescue of meiotic divisions in twine mutant testis.
我们通过重建已知会导致裂殖酵母cdc2⁺产生温度敏感性的突变，构建了温度敏感突变株系（Dmcdc2ts），并分析了果蝇cdc2激酶在精子发生过程中的需求。在高温条件下，Dmcdc2ts突变体中从未形成减数分裂纺锤体和中期板，但染色体仍在晚期精母细胞中浓缩，并且精子细胞分化（精子头部和尾部形成）仍在继续。在twine和twine、Dmcdc2ts双突变体睾丸中也观察到了相同的表型，这与减数分裂所需的cdc2激酶活性由Twine/cdc25磷酸酶激活的观点一致。证实这一观点的是，我们发现已知在有丝分裂前激活cdc2激酶的String/cdc25磷酸酶的异位表达，可部分挽救twine突变体睾丸中的减数分裂。
