State Key Laboratory of Medicinal Chemical Biology, Key Laboratory of Molecular Microbiology and Technology of the Ministry of Education, Department of Microbiology, College of Life Science, Nankai Universitygrid.216938.7, Tianjin, China.
State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China.
Microbiol Spectr. 2022 Dec 21;10(6):e0187222. doi: 10.1128/spectrum.01872-22. Epub 2022 Oct 26.
Soluble -ethylmaleimide-sensitive factor attachment protein receptor (SNARE) proteins play conserved roles in membrane fusion events in eukaryotes and have been documented to be involved in fungal growth and pathogenesis. However, little is known about the roles of SNAREs in trap morphogenesis in nematode-trapping fungi (NTF). , one of the constricting ring-forming NTF, captures free-living nematodes via rapid ring cell inflation. Here, we characterized DdVam7 of , a homolog of the yeast SNARE protein Vam7p. Deletion of significantly suppressed vegetative growth and conidiation. The mutation significantly impaired trap formation and ring cell inflation, resulting in a markedly decreased nematode-trapping ability. A large vacuole could develop in ring cells within ~2.5 s after instant inflation in . In the Δ mutant, the vacuoles were small and fragmented in hyphae and uninflated ring cells, and the large vacuole failed to form in inflated ring cells. The localization of DdVam7 in vacuoles suggests its involvement in vacuole fusion. In summary, our results suggest that DdVam7 regulates vegetative growth, conidiation, and the predatory process by mediating vacuole assembly in , and this provides a basis for studying mechanisms of SNAREs in NTF and ring cell rapid inflation. is a nematode-trapping fungus that can capture nematodes through a constricting ring, the most sophisticated trapping device. It is amazing that constricting ring cells can inflate to triple their size within seconds to capture a nematode. A large centrally located vacuole is a unique signature associated with inflated ring cells. However, the mechanism underpinning trap morphogenesis, especially vacuole dynamics during ring cell inflation, remains unclear. Here, we documented the dynamics of vacuole assembly during ring cell inflation via time-lapse imaging for the first time. We characterized a SNARE protein in (DdVam7) that was involved in vacuole assembly in hyphae and ring cells and played important roles in vegetative growth, conidiation, trap morphogenesis, and ring cell inflation. Overall, this study expands our understanding of biological functions of the SNARE proteins and vacuole assembly in NTF trap morphogenesis and provides a foundation for further study of ring cell rapid inflation mechanisms.
可溶性 - 乙基maleimide 敏感的因子附着蛋白受体 (SNARE) 蛋白在真核生物的膜融合事件中发挥保守作用，并且已经被证明参与真菌的生长和发病机制。然而，关于 SNARE 在线虫诱捕真菌 (NTF) 的诱捕形态发生中的作用知之甚少。, 一种收缩环形成的 NTF，通过快速环细胞膨胀捕获自由生活的线虫。在这里，我们描述了, 一种酵母 SNARE 蛋白 Vam7p 的同源物 DdVam7。Δ 显著抑制了营养生长和分生孢子形成。该突变显著损害了诱捕的形成和环细胞的膨胀，导致线虫诱捕能力显著降低。在快速膨胀后，大约 2.5 s 内可以在环细胞中形成大液泡。在 Δ 突变体中，液泡在菌丝和未膨胀的环细胞中较小且碎片化，并且在膨胀的环细胞中未能形成大液泡。DdVam7 在液泡中的定位表明其参与了液泡融合。总之，我们的结果表明，DdVam7 通过介导 在 中的液泡组装来调节营养生长、分生孢子形成和捕食过程，这为研究 NTF 和环细胞快速膨胀中的 SNARE 机制提供了基础。 是一种可以通过收缩环捕获线虫的线虫诱捕真菌，这是最复杂的诱捕装置。令人惊讶的是，收缩环细胞可以在几秒钟内膨胀到原来的三倍大小以捕获线虫。一个位于中心的大液泡是与膨胀环细胞相关的独特特征。然而，诱捕形态发生的机制，特别是环细胞膨胀过程中的液泡动力学，仍然不清楚。在这里，我们首次通过延时成像记录了环细胞膨胀过程中液泡组装的动力学。我们描述了一种 在 （DdVam7）中参与菌丝和环细胞中液泡组装的 SNARE 蛋白，并在营养生长、分生孢子形成、诱捕形态发生和环细胞膨胀中发挥重要作用。总的来说，这项研究扩展了我们对 SNARE 蛋白和 NTF 诱捕形态发生中液泡组装的生物学功能的理解，并为进一步研究环细胞快速膨胀机制提供了基础。
