Brown University Department of Molecular Biology, Cell Biology, and Biochemistry, United States.
Curr Opin Plant Biol. 2013 Oct;16(5):590-7. doi: 10.1016/j.pbi.2013.08.005. Epub 2013 Sep 7.
Angiosperm pollen tubes extend through pistil tissue to deliver a pair of immotile sperm cells to female gametes for double fertilization. The extended journey of the pollen tube requires extensive cell:cell interactions that guide the pollen tube to its destination and instruct it to stop growing and burst. Once sperm cells are released the molecular exchanges between male and female continue, resulting in sperm activation and gamete fusion. Finally, there is evidence that gamete fusion can feed back on the pollen tube attraction mechanism so that additional pollen tubes can be attracted only if the first sperm cells fail to fertilize. We review progress toward defining the molecules mediating each of these exchanges and describe how small cysteine-rich peptides are a major mode of cellular communication.
被子植物花粉管通过雌蕊组织延伸，将一对不能运动的精子输送到雌性配子体，以进行双受精。花粉管的延伸旅程需要广泛的细胞间相互作用，引导花粉管到达目的地，并指示其停止生长和破裂。一旦精子细胞被释放，雌雄配子之间的分子交换就会继续，导致精子激活和配子融合。最后，有证据表明，配子融合可以反馈到花粉管吸引机制上，因此只有当第一批精子细胞未能受精时，才会吸引更多的花粉管。我们综述了定义介导这些交换的分子的进展，并描述了小富含半胱氨酸的肽类如何成为细胞通讯的主要模式。
