Abstract:
Extracellular vesicles (EVs) are submicron membranous structures and key mediators of intercellular communication.1,2 Recent research has highlighted roles for cilia-derived EVs in signal transduction, underscoring their importance as bioactive extracellular organelles containing conserved ciliary signaling proteins.3,4 Members of the transient receptor potential (TRP) channel polycystin-2 (PKD-2) family are found in ciliary EVs of the green algae Chlamydomonas and the nematode Caenorhabditis elegans5,6 and in EVs in the mouse embryonic node and isolated from human urine.7,8 In C. elegans, PKD-2 is expressed in male-specific EV-releasing sensory neurons, which extend ciliary tips to ciliary pore and directly release EVs into the environment.6,9 Males release EVs in a mechanically stimulated manner, regulate EV cargo content in response to mating partners, and deposit PKD-2::GFP-labeled EVs on the vulval cuticle of hermaphrodites during mating.9,10 Combined, our findings suggest that ciliary EV release is a dynamic process. Herein, we identify mechanisms controlling dynamic EV shedding using time-lapse imaging. Cilia can sustain the release of PKD-2-labeled EVs for 2 h. This extended release doesn\'t require neuronal transmission. Instead, ciliary intrinsic mechanisms regulate PKD-2 ciliary membrane replenishment and dynamic EV release. The kinesin-3 motor kinesin-like protein 6 (KLP-6) is necessary for initial and extended EV release, while the transition zone protein NPHP-4 is required only for sustained EV release. The dynamic replenishment of PKD-2 at the ciliary tip is key to sustained EV release. Our study provides a comprehensive portrait of real-time ciliary EV release and mechanisms supporting cilia as proficient EV release platforms.
摘要:
细胞外囊泡(EV)是亚微米膜结构和细胞间通讯的关键介质。1,2最近的研究强调了纤毛衍生的EV在信号转导中的作用。强调了它们作为含有保守纤毛信号蛋白的生物活性胞外细胞器的重要性.3,4瞬时受体电位(TRP)通道多囊素-2(PKD-2)家族的成员存在于绿藻衣藻和线虫秀丽隐杆线虫5,6的纤毛EV和小鼠胚胎节点的EV中并从人类尿液中分离7,8在秀丽隐杆线虫中,PKD-2在男性特异性EV释放感觉神经元中表达,将纤毛尖端延伸到纤毛孔,并直接将电动汽车释放到环境中。6,9男性以机械刺激的方式释放电动汽车,规范电动汽车货物含量,以应对交配伙伴,并在交配过程中在雌雄同体的外阴角质层上沉积PKD-2::GFP标记的EV。9,10组合,我们的研究结果表明,纤毛EV的释放是一个动态过程.在这里,我们使用延时成像识别控制动态EV脱落的机制。纤毛可以维持PKD-2标记的EV的释放2小时。这种延长释放不需要神经元传递。相反,纤毛内在机制调节PKD-2纤毛膜补充和动态EV释放。驱动蛋白-3运动驱动蛋白样蛋白6(KLP-6)是初始和延长EV释放所必需的,而过渡区蛋白NPHP-4仅用于持续的EV释放。在睫状尖端处动态补充PKD-2是持续EV释放的关键。我们的研究提供了实时纤毛EV释放和支持纤毛作为熟练EV释放平台的机制的全面描述。