Extracellular matrix functions

Barros, C.S., Franco, S.J., MuUer, U., 2011. Extracellular matrix functions in the nervous system. Cold Spring Harb. Perspect. Biol. 3, a005108. 

In biology, extracellular matrix (ECM) is the extracellular part of animal tissue that usually provides structural support to the cells in addition to performing various other important functions. ECM is the defining feature of connective tissue in animals. ECM includes the interstitial matrix and the basement membrane. 

Integrins constitute a large family of a (3 heterodimeric cell surface, transmembrane proteins that interact with a large number of extracellular matrix components through a metal ion-dependent interaction. The term integrin reflects their function in integrating cell adhesion and migration with the cystoskeleton. 

Thus far, microtubules and actin filaments and their associated proteins have been discussed to advantage as independent cytoskeletal components. In actual fact, all of the components of the cytoskeleton (including intermediate filaments) are precisely integrated with one another (Langford, 1995), as well as with various cytoplasmic organelles, the nuclear membrane, the plasma membrane, and the extracellular matrix. In its totality the cytoskeleton subserves many coordinated and regulated functions in the cell ... 

The secretion of extracellular matrix proteins is also a function of smooth muscle cells but, since it occurs concurrently with other activities, it does not seem to constitute a physiological state. However, the fraction of the cellular resources which are devoted to it must be regulated these regulatory mechanisms are virtually unknown. In addition, it should be anticipated that autocrine activity occurs as well, involving peptides, prostaglandins, cytokines, and nitric oxide. 

Petrie TA, Garcia AJ (2009) Extracellular matrix-derived ligands for seledive integrin binding to control cell function. In Puleo DA (ed) Biological interactions on materials surfaces. Springer, New York... 

The identified genes code for a variety of proteins, including transcription factors that are important for inner-ear development, cytoskeleton proteins that are responsible for the specialized architecture of hair cells, extracellular matrix molecules that make up some of the specialized acellular structures of the inner ear, and still others whose function is not yet clear. 

Usher II is caused by mutations in at least four genes only one, usherin, has been identified. Usherin is an extracellular matrix protein of unknown function it is found in basement membranes in the eye and ear (and in other tissues as well). Similarly, at least two genes underlie Usher III, but only one (clarin-1) has been cloned. The function of clarin-1 is unknown. 

Schonherr, E. and Hausser, H., Extracellular matrix and cytokines A functional unit, Devel. Immunol., 7, 89, 2000. 

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