Fission yeast Myo51 is a meiotic spindle pole body component with discrete roles during cell fusion and spore formation
Fission yeast Myo51 is a meiotic spindle pole body component with discrete roles during cell fusion and spore formation
复制标题
DOI：
10.1242/jcs.055202
复制
发表时间：
2009-12-01
影响因子：
4
通讯作者：
Mulvihill, Daniel P.
中科院分区：
文献类型：
--
作者：
Doyle, Alex;Martin-Garcia, Rebeca;Mulvihill, Daniel P.
V类肌球蛋白是二聚肌动蛋白相关的马达蛋白，其将细胞货物递送至离散的细胞位置。裂变酵母具有两种V类肌球蛋白，Myo 51和Myo 52。虽然Myo 52已被证明在液泡分布，胞质分裂和细胞生长中发挥作用，但Myo 51在营养生命周期中还没有可辨别的功能。在这里，我们揭示了这种马达蛋白在交配和减数分裂过程中的不同功能。不仅Myo 51在接合后瞬时定位于细胞融合位点处的病灶，而且Myo 51球状尾的过表达也导致细胞融合的破坏。在减数分裂前期完成后，Myo 51定位于纺锤体极体（SPB）的外部，在那里它一直保持到减数分裂II完成。Myo 51与SPBs的关联不依赖于肌动蛋白或分隔起始网络（SIN）;然而，它依赖于稳定的微管细胞骨架和Cdc 2-CyclinB复合物的存在。我们观察到一个快速和动态的交换Myo 51在SPB在减数分裂I，但没有减数分裂II。最后，我们发现Myo 51在减数分裂完成后调节孢子形成中具有重要作用。
Class V myosins are dimeric actin-associated motor proteins that deliver cellular cargoes to discrete cellular locations. Fission yeast possess two class V myosins, Myo51 and Myo52. Although Myo52 has been shown to have roles in vacuole distribution, cytokinesis and cell growth, Myo51 has no as yet discernible function in the vegetative life cycle. Here, we uncover distinct functions for this motor protein during mating and meiosis. Not only does Myo51 transiently localise to a foci at the site of cell fusion upon conjugation, but overexpression of the Myo51 globular tail also leads to disruption of cell fusion. Upon completion of meiotic prophase Myo51 localises to the outside of the spindle pole bodies (SPBs), where it remains until completion of meiosis II. Association of Myo51 with SPBs is not dependent upon actin or the septation initiation network (SIN); however, it is dependent on a stable microtubule cytoskeleton and the presence of the Cdc2-CyclinB complex. We observe a rapid and dynamic exchange of Myo51 at the SPB during meiosis I but not meiosis II. Finally, we show that Myo51 has an important role in regulating spore formation upon completion of meiosis.