Centrins, also known as caltractins, are a family of
calcium
Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar t ...
-binding
phosphoproteins found in the
centrosome
In cell biology, the centrosome (Latin centrum 'center' + Greek sōma 'body') (archaically cytocentre) is an organelle that serves as the main microtubule organizing center (MTOC) of the animal cell, as well as a regulator of cell-cycle pro ...
of
eukaryote
Eukaryotes () are organisms whose cells have a nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the three domains of life. Bact ...
s. Centrins are present in the
centrioles and pericentriolar lattice.
Human centrin genes are
CETN1,
CETN2 and
CETN3.
History
Centrin was first isolated and characterized from the flagellar roots
of the green alga ''
Tetraselmis striata'' in 1984.
Function
Centrins are required for duplication of centrioles.
They may also play a role in severing of
microtubules by causing calcium-mediated contraction.
The majority of centrin in the cell is non-centrosomal whose function is not yet clear.
Structure
Centrin belongs to the
EF-hand superfamily of calcium-binding proteins and has four calcium-binding EF-hands.
It has a molecular weight of 20 kDa.
See also
*
Centriole
*
Centrosome
In cell biology, the centrosome (Latin centrum 'center' + Greek sōma 'body') (archaically cytocentre) is an organelle that serves as the main microtubule organizing center (MTOC) of the animal cell, as well as a regulator of cell-cycle pro ...
References
Protein families
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