Chromosome dynamics during the G2/M transition in meiosis

在生产精子和卵子的过程中，细胞必须将染色体数量减半，否则产生的胎儿就会含有太多的染色体。这需要一个特殊的细胞分裂，染色体首先找到他们的伴侣，然后从他们身上分离--结婚后就是离婚。细胞如何确保每个卵子或精子只包含一套完整的染色体，对于人类来说是23条？染色体在序列同一性的基础上配对，形成称为交叉的特殊连接，在显微镜下看起来像希腊字母chi。配对和交叉的形成由一种称为联会复合体的结构促进；当交叉形成时，联会复合体被破坏，细胞准备分裂染色体对。我们正在研究联会复合体的破坏是如何促进的，以及它是如何与交叉的形成相协调的。为此，我们使用面包师酵母作为模式生物。贝克的酵母为交叉和联会复合体是如何形成的提供了有价值的见解，我们预计管理其分解的一些基本原理也将适用于人类。

During the production of sperm and eggs, cells have to half the number of chromosomes, otherwise the resulting foetus will contain too many. This requires a specialized cell division where chromosomes first find their partner and then split from them- a marriage followed by divorce. How do cells ensure that each egg or sperm contains exactly one full set of chromosomes, 23 in the case of humans? Chromosomes pair on the basis of sequence identity and form specialized connections called chiasmata that look like the Greek letter chi under the microscope. Pairing and the formation of chiasmata is facilitated by a structure called the synaptonemal complex; when chiasmata form the synaptonemal complex is broken down and cells get ready to split up the chromosome pairs. We are investigating how the breakdown of the synaptonemal complex is facilitated and how is it coordinated with formation of chiasmata. To this end, we use baker‘s yeast as a model organism. Baker‘s yeast has provided valuable insight into how chiasmata and the synaptonemal complex are formed and we expect that some of the basic principles that govern its breakdown will also be relevant in humans.