Meiosis-specific gene functions and cell cycle control in Drosophila spermatocytes

真菌、植物和动物在减数分裂过程中基本上利用相同的基因组单倍体化过程。同源染色体在减数分裂前S期复制后配对。一般来说，由于减数分裂重组产生的交叉，这些染色体对保持在一起。这些染色体在第一次减数分裂时分离，并分布在两个相对的纺锤极上。在随后的第二次减数分裂中，产生的两个染色体群中的每一个都被整合到另一个纺锤体中，该纺锤体将每条染色体的两个染色单体分离到相对的纺锤极上，从而产生四个单倍体核。然而，在分子水平上，减数分裂的基本方面似乎保存得很差，因此没有得到充分的理解。令人惊讶的是，雄性黑腹果蝇的减数分裂不包括减数分裂重组，减数分裂分裂可以很容易地进行体内成像。结合果蝇强大的遗传方法，我们将在我们的项目中利用雄性减数分裂的这些特殊性质。我们将分析转录控制的机制和基因的功能，这些基因在减数分裂期间只在两性中表达。将特别注意触发减数分裂开始的分子调控。

Fungi, plants and animals exploit in essence an identical procedure for genome haploidization during meiosis. Homologous chromosomes are paired after duplicaton during the premeiotic S phase. In general the pairs are kept together by chiasmata which result from meiotic recombination. These chromosome pairs are separated during the first meiotic division and distributed onto the two opposite spindle poles. During the subsequent second meiotic division, each of the two resulting chromosome groups is integrated into another spindle apparatus which segregates the two chromatids of every chromosome onto opposite spindle poles, resulting in four haploid nuclei. However, at the molecular level even fundamental aspects of meiosis appear to have been poorly conserved and are therefore inadequately understood. Meiosis in male Drosophila melanogaster flies surprisingly does not include meiotic recombination and the meiotic divisions can be followed readily by in vivo imaging. In combination with the powerful genetic methodology available in Drosophila we will exploit these special properties of male meiosis in our project. We will analyse the mechanism of transcriptional control and the function of genes which are expressed in both sexes exclusively during meiosis. Special attention will be given to the molecular regulation triggering the onset of the meiotic divisions.