Wang Mengying, Danz Katherine, Ly Vanessa, Rojas-Pierce Marcela
Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC, USA.
NPJ Microgravity. 2022 Sep 6;8(1):38. doi: 10.1038/s41526-022-00226-3.
The spaceflight environment of the International Space Station poses a multitude of stresses on plant growth including reduced gravity. Plants exposed to microgravity and other conditions on the ISS display root skewing, changes in gene expression and protein abundance that may result in changes in cell wall composition, antioxidant accumulation and modification of growth anisotropy. Systematic studies that address the effects of microgravity on cellular organelles are lacking but altered numbers and sizes of vacuoles have been detected in previous flights. The prominent size of plant vacuoles makes them ideal models to study organelle dynamics in space. Here, we used Arabidopsis zigzag-1 (zig-1) as a sensitized genotype to study the effect of microgravity on plant vacuole fusion. Wortmannin was used to induce vacuole fusion in seedlings and a formaldehyde-based fixation protocol was developed to visualize plant vacuole morphology after sample return, using confocal microscopy. Our results indicate that microgravity enhances the zig-1 phenotype by reducing hypocotyl growth and vacuole fusion in some cells. This study demonstrates the feasibility of chemical inhibitor treatments for plant cell biology experiments in space.
国际空间站的航天环境对植物生长造成了诸多压力，包括重力减小。暴露于国际空间站微重力及其他条件下的植物会出现根扭曲、基因表达和蛋白质丰度变化，这可能导致细胞壁组成、抗氧化剂积累以及生长各向异性改变。目前缺乏针对微重力对细胞器影响的系统性研究，但在以往飞行中已检测到液泡数量和大小的改变。植物液泡的显著大小使其成为研究空间细胞器动态的理想模型。在此，我们使用拟南芥曲折-1（zig-1）作为敏感基因型来研究微重力对植物液泡融合的影响。渥曼青霉素用于诱导幼苗中的液泡融合，并开发了一种基于甲醛的固定方案，以便在样品返回后使用共聚焦显微镜观察植物液泡形态。我们的结果表明，微重力通过减少某些细胞中的下胚轴生长和液泡融合来增强zig-1表型。这项研究证明了化学抑制剂处理用于空间植物细胞生物学实验的可行性。
