In contrast, Annexin 1, one of the earliest responders to plasma membrane injury (Leikina et al., 2015; McNeil, Rescher, Gerke, & McNeil, 2006), does not appear to be essential for plasma membrane repair (Leikina et al., 2015; McNeil et al., 2006). Intriguingly, PIP2 is needed for PLD activity suggesting the possibility that a feed-forward loop leads to increasing PIP2 concentrations as repair progresses ultimately facilitating the necessary build-up of F-actin (Figure 1B). Many organisms and tissues display the ability to heal and regenerate as needed for normal physiology and as a result of pathogenesis. While small injuries to the plasma membrane (on the nanometer scale) can be spontaneously resealed due to the line tension imposed by plasma membrane lipids alone (McNeil & Terasaki, 2001), larger membrane injuries (on the micron scale) require a series of coordinated mechanisms to undergo repair. Membranes Self-repair Biological Strategy AskNature Daumke O, Lundmark R, Vallis Y, Martens S, Butler PJG, & McMahon HT (2007). PIP2 accumulation was observed as early as 4 seconds in mouse myofibers; however, it continued to accumulate even 1 minute post-injury suggesting a role in the later stages of repair (Demonbreun et al., 2016). As structural components of the plasma membrane, lipids are responsible for contributing to membrane tension, rigidity, and overall shape. (2017). Bacterial pore-forming toxins oligomerize and insert in the plasma membrane of target cells forming a diffusible pore. 2012 Sep-Oct;52(3-4):191-5. doi: 10.1016/j.ceca.2012.06.003. PMC Learn whats new on AskNature by signing up for our e-newsletter. Viral infection controlled by a calcium-dependent lipid-binding module in ALIX. official website and that any information you provide is encrypted the contents by NLM or the National Institutes of Health. There also exists lateral heterogeneity of lipid composition within each leaflet, which is demonstrated by the formation of lipid microdomains, such as the sphingomyelin and cholesterol-rich domains that exist interspersed among the phospholipids throughout the plasma membrane (Cebecauer et al., 2018; Sezgin, Levental, Mayor, & Eggeling, 2017) (Figure 2B). See this image and copyright information in PMC. Influx of calcium from the extracellular space, as well as locally increased oxidation, both trigger lipid signaling that is required for repair. This process, facilitated by the dysferlin-mediated release of acid sphingomyelinase (Defour et al., 2014) creates microdomains of ceramide from sphingomyelin. Phosphatidylinositol is found in many cell types and tissues, but is particularly abundant in the brain. Bianco F, Perrotta C, Novellino L, Francolini M, Riganti L, Menna E, Clementi E. (2009). FOIA However, shear force on the membrane increases the kinetic energy required for lipid mixing (i.e. Thus, the signaling role of lipids affects membrane structure and how the wound is eventually resealed and remodeled, returning the plasma membrane to homeostasis. Glycerol-3-phosphate is used to generate PA as well as PG through the intermediate phosphatidylglycerol phosphate (PGP). 2022 May 15;23(10):5525. doi: 10.3390/ijms23105525. In this case, cholesterol actually increases the fluidity among these lipids, which prevents them from forming a gel-like phase that is incompatible with the overall fluid nature of the plasma membrane (Krause & Regen, 2014). Please enable it to take advantage of the complete set of features! Exocytic fusion reduces membrane tension, and vesicle-vesicle fusion events provide a patch as a replacement for the membrane barrier missing at the disruption site.
