Mardini Majd, Ermolaev Aleksey, Kuznetsov Alexey Yu, Zhevnerov Alexey V, Buravkov Sergey, Khrustaleva Ludmila
Center of Molecular Biotechnology, Russian State Agrarian University-Moscow Timiryazev Agricultural Academy, Moscow, Russia.
Laboratory of Marker-Assisted and Genomic Selection of Plants, All-Russian Research Institute of Agricultural Biotechnology, Moscow, Russia.
PLoS One. 2025 Apr 7;20(4):e0321197. doi: 10.1371/journal.pone.0321197. eCollection 2025.
Pollenkitt, a sticky substance produced by the tapetal cells of pollen grains, plays a crucial role in pollen functionality, yet it remains an understudied component in plant biology. In this study, we investigated the role of pollenkitt in onion (Allium cepa) pollen, focusing on its effects on pollen germination, DNase activity, fatty acid composition, and ultrastructure. Our findings reveal that pollenkitt is essential for successful onion pollen germination and tube growth on the stigma, as its removal significantly inhibited these processes. Additionally, we demonstrated that onion pollenkitt exhibits DNase activity, degrading plasmid DNA in a concentration-dependent manner, with EDTA effectively inhibiting the degradation. Gas chromatography identified 20 fatty acids in pollenkitt, with a predominance of unsaturated fatty acids. Using scanning electron microscopy (SEM), we showed structural differences between pollen grains with and without pollenkitt, and we observed the process of pollenkitt removal from the surface of pollen grains by water washing. These results offer valuable insights for future research aimed at optimizing pollen-mediated gene-editing systems and highlight the importance of considering pollenkitt in such applications.
花粉壁含油层是由花粉粒绒毡层细胞产生的一种粘性物质，在花粉功能中起着关键作用，但在植物生物学中它仍是一个研究较少的成分。在本研究中，我们研究了花粉壁含油层在洋葱（葱属植物）花粉中的作用，重点关注其对花粉萌发、脱氧核糖核酸酶活性、脂肪酸组成和超微结构的影响。我们的研究结果表明，花粉壁含油层对于洋葱花粉在柱头上成功萌发和花粉管生长至关重要，因为去除它会显著抑制这些过程。此外，我们证明洋葱花粉壁含油层具有脱氧核糖核酸酶活性，以浓度依赖的方式降解质粒DNA，而乙二胺四乙酸有效地抑制了这种降解。气相色谱法鉴定出花粉壁含油层中有20种脂肪酸，其中不饱和脂肪酸占主导。使用扫描电子显微镜（SEM），我们展示了有和没有花粉壁含油层的花粉粒之间的结构差异，并且我们观察到通过水洗从花粉粒表面去除花粉壁含油层的过程。这些结果为未来旨在优化花粉介导的基因编辑系统的研究提供了有价值的见解，并突出了在这类应用中考虑花粉壁含油层的重要性。
