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:
“A special feature of the structure of our book is the monstrous but perfectly organic part that eavesdropping plays in it.”
—Vladimir Nabokov (1899–1977)
“The philosopher believes that the value of his philosophy lies in its totality, in its structure: posterity discovers it in the stones with which he built and with which other structures are subsequently built that are frequently better—and so, in the fact that that structure can be demolished and yet still possess value as material.”
—Friedrich Nietzsche (1844–1900)
“With sixty staring me in the face, I have developed inflammation of the sentence structure and definite hardening of the paragraphs.”
—James Thurber (1894–1961)