Synergid cell calcium oscillations refine understanding of FERONIA/LORELEI signaling during interspecific hybridization
Synergid cell calcium oscillations refine understanding of FERONIA/LORELEI signaling during interspecific hybridization
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DOI：
10.1007/s00497-023-00483-6
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发表时间：
2023-11
影响因子：
3.4
通讯作者：
Nathaniel Ponvert;Mark A. Johnson
中科院分区：
文献类型：
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作者：
Nathaniel Ponvert;Mark A. Johnson
来自近亲物种的花粉管和缺乏花粉管MYB转录因子的突变体能够启动依赖于FER/ lre的协同细胞钙振荡。生殖隔离导致新物种的进化；然而，维持同域物种间生殖障碍的分子机制尚不明确。在开花植物中，精细胞是不动的，通过花粉粒传递给雌性配子。落在柱头表面后，花粉粒萌发出一个极化的延伸，即花粉管，进入花组织。花粉管通过雌性配子的极向延伸生长，并将精子运送到细胞质中，然后向卵细胞侧面的协同细胞发出信号，表明自己的到来和身份。如果信号传递成功，花粉管和接受性协同细胞破裂，精子细胞被释放出来与雌性配子融合。为了更好地了解生殖过程中的细胞-细胞识别以及近亲物种之间如何维持生殖屏障，我们在种间杂交过程中研究了花粉管启动的协同细胞钙离子动力学。据观察，种间花粉管成功地触发了协同细胞钙振荡，这是生殖成功的标志，但下游关键信号基因的信号传导失败，精子没有被释放。本研究进一步确定了花粉管协同细胞信号传导是种间杂交的关键障碍，并表明FERONIA/LORELEI信号传导机制在花粉管接收过程中发挥多重平行作用。
Key messagePollen tubes from closely related species and mutants lacking pollen tube MYB transcription factors are able to initiate FER/LRE-dependent synergid cell calcium oscillations.AbstractReproductive isolation leads to the evolution of new species; however, the molecular mechanisms that maintain reproductive barriers between sympatric species are not well defined. In flowering plants, sperm cells are immotile and are delivered to female gametes by the pollen grain. After landing on the stigmatic surface, the pollen grain germinates a polarized extension, the pollen tube, into floral tissue. After growing via polar extension to the female gametes and shuttling its cargo of sperm cells through its cytoplasm, the pollen tube signals its arrival and identity to synergid cells that flank the egg. If signaling is successful, the pollen tube and receptive synergid cell burst, and sperm cells are released for fusion with female gametes. To better understand cell–cell recognition during reproduction and how reproductive barriers are maintained between closely related species, pollen tube-initiated synergid cell calcium ion dynamics were examined during interspecific crosses. It was observed that interspecific pollen tubes successfully trigger synergid cell calcium oscillations—a hallmark of reproductive success—but signaling fails downstream of key signaling genes and sperm are not released. This work further defines pollen tube–synergid cell signaling as a critical block to interspecific hybridization and suggests that the FERONIA/LORELEI signaling mechanism plays multiple parallel roles during pollen tube reception.