Structure
The asymmetric structure consists of an N-terminal beta-trefoil domain and a C-terminal alpha helical domain with a folding pattern similar to an armadillo repeat fold. The split formed by the two terminals contains multiple arginine and lysine residues that coordinate the three phosphoryl groups of InsP3R. The InsP3R complex is formed of four 313 kDa subunits. In amphibians, fish and mammals there are 3 paralogs and these can form homo- or hetero-oligomers. InsP3R-1 is the most widely expressed of these three and is found in all tissue types and all developmental stages of life. It is additionally the means for further InsP3 receptor diversity in that it has as many as four splice sites with as many as 9 different optional exons or exon variants. Combinations of these can be introduced into a given transcript in order to modulate its pharmacological activity.
Read more about this topic: Inositol Trisphosphate Receptor
Famous quotes containing the word structure:
“Why does philosophy use concepts and why does faith use symbols if both try to express the same ultimate? The answer, of course, is that the relation to the ultimate is not the same in each case. The philosophical relation is in principle a detached description of the basic structure in which the ultimate manifests itself. The relation of faith is in principle an involved expression of concern about the meaning of the ultimate for the faithful.”
—Paul Tillich (1886–1965)
“A structure becomes architectural, and not sculptural, when its elements no longer have their justification in nature.”
—Guillaume Apollinaire (1880–1918)
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—Vladimir Nabokov (1899–1977)