Abstract

Reproduction is an essential process for all organisms. Although our understanding of the reproductive mechanism in angiosperms has rapidly advanced in recent years, it still lags behind that of gymnosperms. As an ancient gymnosperm, Ginkgo biloba has a remarkable evolutionary history and occupies an important phylogenetic position, representing one of the most ancient and primitive modes of reproduction among seed plants. G. biloba is an archegoniate, where an egg cell develops inside an archegonium; it has a particular pollen chamber and archegonial chamber along with flagellated gametes (spermatozoids). Among these processes, secretions play an important role. In this study, we review the progress on understanding the mechanisms underlying the production and function of pollination drops (PDs), and fertilization fluid in G. biloba. We also highlight recent achievements that have considerably advanced our understanding of the interactions between PDs and pollen, and how PDs are endogenously and intracellularly transported. Finally, we discuss novel insights into the small RNAs of PD transport and the mechanisms of precisely guiding pollen tube growth in G. biloba. By reviewing these results, we demonstrate the structural patterns of G. biloba pollination and fertilization, thus reproducing the uniqueness of the sexual reproduction of ancient plants.

摘要

繁殖是所有生物的基本过程。尽管近年来我们对被子植物生殖机制的认识迅速提高，但仍落后于裸子植物。银杏作为一种古老的裸子植物，具有非凡的进化历史，在系统发育中占有重要地位，是种子植物中最古老、最原始的繁殖方式之一。克。银杏是archegoniate，卵细胞在archegonium内发育；它有一个特殊的花粉室和弓形室以及有鞭毛的配子（精子）。在这些过程中，分泌物起着重要作用。在本研究中，我们回顾了了解授粉液滴 (PDs) 和受精液在G中的产生和功能的潜在机制的进展。银杏_ 我们还强调了最近取得的成就，这些成就大大提高了我们对 PD 和花粉之间相互作用的理解，以及 PD 如何进行内源性和细胞内运输。最后，我们讨论了对 PD 转运的小 RNA 的新见解以及精确引导G中花粉管生长的机制。银杏. 通过回顾这些结果，我们展示了G的结构模式。银叶授粉受精，从而再现了古代植物有性繁殖的独特性。