Department of Molecular Biology and Genetics, Biotechnology Building, Cornell University, Ithaca, NY 14853, USA.
Biological Sciences Department, State University of New York, Cortland, NY 13045, USA.
Curr Opin Plant Biol. 2020 Dec;58:25-32. doi: 10.1016/j.pbi.2020.10.005. Epub 2020 Nov 1.
Stromules are thin tubular extensions of the plastid compartment surrounded by the envelope membrane. A myriad of functions have been proposed for them, and they likely have multiple roles. Recent work has illuminated aspects of their formation, especially the important of microtubules in their movement and microfilaments in anchoring. A variety of biotic and abiotic stresses result in induction of stromule formation, and in recent years, stromule formation has been strongly implicated as part of the innate immune response. Both stromules and chloroplasts relocate to surround the nucleus when pathogens are sensed, possibly to supply signaling molecules such as reactive oxygen species. In addition to the nucleus, stromules have been observed in close proximity to other compartments such as mitochondria, endoplasmic reticulum, and the plasma membrane, potentially facilitating exchange of substrates and products to carry out important biosynthetic pathways. Much remains to be learned about the identity of proteins and other molecules released from chloroplasts and stromules and how they function in plant development and defense.
类囊体丝是由质膜包围的类囊体腔的细管状延伸物。人们提出了无数种关于它们的功能，它们可能具有多种作用。最近的研究揭示了它们形成的一些方面，特别是微管在它们运动中的重要性和微丝在锚定中的重要性。各种生物和非生物胁迫会导致类囊体丝的形成，近年来，类囊体丝的形成被强烈暗示为先天免疫反应的一部分。当感知到病原体时，类囊体丝和叶绿体都会重新定位到细胞核周围，可能是为了提供信号分子，如活性氧。除了细胞核，类囊体丝还被观察到与其他细胞器如线粒体、内质网和质膜紧密相邻，可能有助于交换底物和产物，以进行重要的生物合成途径。关于从叶绿体和类囊体丝释放的蛋白质和其他分子的身份以及它们如何在植物发育和防御中发挥作用，仍有许多需要了解。
