Pérez-Hidalgo Livia, Rozalén Ana Elisa, Martín-Castellanos Cristina, Moreno Sergio
Instituto de Biología Molecular y Celular del Cáncer, CSIC/Universidad de Salamanca, Campus Miguel de Unamuno, Salamanca, Spain.
J Cell Sci. 2008 May 1;121(Pt 9):1383-92. doi: 10.1242/jcs.023812. Epub 2008 Apr 8.
Septation and spore formation in fission yeast are compartmentalization processes that occur during the mitotic and meiotic cycles, and that are regulated by the septation initiation network (SIN). In mitosis, activation of Sid2 protein kinase transduces the signal from the spindle pole body (SPB) to the middle of the cell in order to promote the constriction of the actomyosin ring. Concomitant with ring contraction, membrane vesicles are added at the cleavage site to enable the necessary expansion of the cell membrane. In meiosis, the forespore membrane is synthesized from the outer layers of the SPB by vesicle fusion. This membrane grows and eventually engulfs each of the four haploid nuclei. The molecular mechanism that connects the SIN pathway with synthesis of the forespore membrane is poorly understood. Here, we describe a meiosis-specific Sid2-like kinase (Slk1), which is important for the coordination of the growth of the forespore membrane with the meiotic nuclear divisions. Slk1 and Sid2 are required for forespore membrane biosynthesis and seem to be the final output of the SIN pathway in meiosis.
裂殖酵母中的隔膜形成和孢子形成是在有丝分裂和减数分裂周期中发生的区室化过程，由隔膜起始网络（SIN）调控。在有丝分裂中，Sid2蛋白激酶的激活将信号从纺锤极体（SPB）传导至细胞中部，以促进肌动球蛋白环的收缩。伴随环的收缩，在分裂位点添加膜泡，以使细胞膜能够进行必要的扩张。在减数分裂中，前孢子膜通过囊泡融合从SPB的外层合成。该膜生长并最终包裹四个单倍体核中的每一个。将SIN途径与前孢子膜合成联系起来的分子机制尚不清楚。在这里，我们描述了一种减数分裂特异性的Sid2样激酶（Slk1），它对于前孢子膜生长与减数分裂核分裂的协调很重要。Slk1和Sid2是前孢子膜生物合成所必需的，似乎是减数分裂中SIN途径的最终输出。
