Coordination of phosphoinositides and RAB GTPases in membrane trafficking events

膜运输事件中磷酸肌醇和 RAB GTP 酶的协调

• 批准号: RGPIN-2016-03730
• 负责人: Jean, Steve
• 金额: $ 2.62万
• 依托单位: Université de Sherbrooke
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=629210
• 关键词: Coordination; phosphoinositides; RAB; GTPases; membrane

Every cells of our body are composed of multiple types of compartments, all segregated from each other’s. These compartments, called organelles and vesicles, are delimitated by membranes. These membranes are highly controlled and the mechanisms regulating them are collectively named ‘membrane trafficking’ events. Significantly, these organelles and vesicles exchange a lot of material. Since, they mix together through the exchange of material, molecular mechanisms are required to control and maintain their identities. One could compare the exchange of material between organelles as mixing different colors of Play-Doh. If no precautions are taken, then over time, the Play-Doh will turn brown since all colors will be mixed. In our cells, two major classes of membrane identity regulators were identified, and are called RAB GTPases and phosphoinositides. The action of both maintains compartment distinctiveness, and allows the different organelles and vesicles to exchange material and maintain their identities. From the Play-Doh analogy, one could compare RABs and phosphoinositides to brushes and different colors of paint. Studies have found that RABs and phosphoinositides work together, like a brush needs paint. Surprisingly, it was shown in cells that a phosphoinositide made by different processes affects the function of a RAB in various manners. In the Play-Doh example, we could compare it to different white colors from different companies sticking more or less to a brush. As such, although all the paints are white, they won't have the same effect on the Play-Doh.

我们身体的每个细胞都是由多种类型的隔室组成的，这些隔室彼此隔离。这些被称为细胞器和囊泡的隔室被膜分隔开。这些膜受到高度控制，调节它们的机制统称为“膜运输”事件。值得注意的是，这些细胞器和囊泡交换了大量的物质。由于它们通过物质交换混合在一起，需要分子机制来控制和保持它们的特性。我们可以把细胞器之间的物质交换比作混合不同颜色的培乐多。如果不采取预防措施，那么随着时间的推移，培乐多会变成棕色，因为所有的颜色都会混合在一起。在我们的细胞中，确定了两类主要的膜身份调节因子，它们被称为RAB gtp酶和磷酸肌苷。两者的作用保持了隔室的独特性，并允许不同的细胞器和囊泡交换物质并保持其身份。从培乐多橡皮泥的类比中，我们可以将RABs和磷酸肌苷比作画笔和不同颜色的油漆。研究发现，RABs和磷酸肌苷协同工作，就像画笔需要油漆一样。令人惊讶的是，在细胞中显示，由不同过程产生的磷酸肌肽以各种方式影响RAB的功能。在培乐多的例子中，我们可以将其与不同公司的不同白色或多或少地粘在刷子上进行比较。因此，虽然所有的油漆都是白色的，但它们对培乐多的效果却不同。