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Learning by Building a Cell Membrane from Purified Components
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Mr. Abrar Bhat*
Email: abrarbio001@gmail.com
Cell to biology is what atom is to physics. It’s the basic unit of life (unless you are a virus). What defines a cell from
its outside environment is the cell membrane. The cell membrane facilitates the exchange of material and information necessary for cell survival. It senses various chemical and mechanical signals. It allows the intake of nutrients, fluids and drugs, and the release of waste materials, hormones and enzymes. It also acts as the entry site for pathogens such as bacteria and viruses. To carry out these functions, the cell membrane needs to strictly control its local composition and architecture.
The cell membrane is a complex mixture of lipids, proteins and sugars. Lipid molecules are arranged in the form of an asymmetric fluid bilayer: the two leaflets of the bilayer
actively maintain dissimilar lipid and protein compositions. Proteins are present on both the leaflets and across the bilayer, and can move around within the lipid bilayer. Certain membrane proteins contain various sugar and lipid moieties, which are thought to be essential for their structure, localization and function on the membrane.
When the cell membrane receives a signal, its components protein and lipids are organized into structures ranging from clusters of a few molecules to micron-sized patches. This localized rearrangement is essential for transmitting the signal inside the cell and generating an appropriate response. The cellular response can be anything like (a) activation of a cytoplasmic enzyme, (b) inflow or outflow of ions such as sodium and calcium,
* Mr. Abrar Bhat, PhD Scholar from National Centre for Biological Sciences, Tata Institute for Fundamental Research, Bengaluru, is pursuing his research on “Understanding how the Plasma Membrane is Built and Organized from Active Principles, by Employing a Combination of Biochemical Reconstitution, Cell Culture and Quantitative Imaging”. His popular science story entitled “Learning by Building a Cell Membrane from Purified Components” has been selected for AWSAR Award.