Lamella (cell biology)

From Wikipedia, the free encyclopedia
Jump to: navigation, search

A lamella (plural: "lamellae") in biology refers to a thin layer, membrane, or plate of tissue. [1]This is a very broad definition, and can refer to many different structures. Any thin layer of organic tissue can be called a lamella and there is a wide array of functions an individual layer can serve. For example, an intercellular lipid lamella is formed when lamellar disks fuse together to form a lamellar sheet. It is believed that these disks are formed from vesicles, giving the lamellar sheet a lipid bilayer that plays a role in water diffusion.[2]

Another instance of cellular lamellae, can be seen in chloroplasts. Thylakoid membranes are actually a system of lamellar membranes working together, and are differentiated into different lamellar domains. This lamellar system allows plants to convert sunlight into energy.[3] Chloroplasts are characterized by a system of membranes embedded in a hydrophobic proteinaceous matrix, or stroma. The basic unit of the membrane system is a flattened single vesicle called the thylakoid; thylakoids stack into grana. All the thylakoids of a granum are connected with each other, and the grana are connected by intergranal lamellae.[4]

It is placed between the two primary cell walls of two plant cells and made up of intracellular matrix. The lamella comprises a mixture of polygalacturons (D-galacturonic acid) and neutral carbohydrates. It is soluble in the pectinase enzyme.

Lamella, in cell biology, is also used to describe the leading edge of a motile cell, of which the lamellipodia is the most forward portion.[5]

The lipid bilayer core of biological membranes is also called lamellar phase.[6] Thus, each bilayer of multilamellar liposomes and wall of a unilamellar liposome is also referred to as a lamella.

See also[edit]


References[edit]

  1. ^ Merriam-webster.com. (2017). Definition of LAMELLA. [online] Available at: https://www.merriam-webster.com/dictionary/lamella
  2. ^ Swartzendruber, Donald C; Wertz, Philip W; Kitko, David J; Madison, Kathi C; Downing, Donald T (1989). "Molecular models of the Intercellular Lipid Lamellae in Mammalian Stratum Corneum". Journal of Investigative Dermatology. 92 (2): 251–7. doi:10.1111/1523-1747.ep12276794. PMID 2918233. 
  3. ^ Shimoni, E (2005). "Three-Dimensional Organization of Higher-Plant Chloroplast Thylakoid Membranes Revealed by Electron Tomography". The Plant Cell Online. 17 (9): 2580–6. doi:10.1105/tpc.105.035030. JSTOR 4130938. PMC 1197436Freely accessible. PMID 16055630. 
  4. ^ Oxford Dictionary of Biochemistry and Molecular Biology, Oxford University Press[page needed]
  5. ^ http://cellix.imba.oeaw.ac.at/motility/lamellipodia
  6. ^ https://www.nature.com/articles/35097046

Further reading[edit]

  • Yashroy, R. C (1990). "Lamellar dispersion and phase separation of chloroplast membrane lipids by negative staining electron microscopy". Journal of Biosciences. 15 (2): 93–8. doi:10.1007/BF02703373.