View source for 1ttc

[[Image:1ttc.gif|left|200px]]<br />
<applet load="1ttc" size="450" color="white" frame="true" align="right" spinBox="true" 
caption="1ttc, resolution 1.7&Aring;" />
'''THE X-RAY CRYSTAL STRUCTURE REFINEMENTS OF NORMAL HUMAN TRANSTHYRETIN AND THE AMYLOIDOGENIC VAL30MET VARIANT TO 1.7 ANGSTROMS RESOLUTION'''<br />

==Overview==
The x-ray crystal structures of normal human transthyretin (prealbumin), and the amyloidogenic Val-30-Met variant have been refined at 1.7-A, resolution to R-values of 0.168 and 0.179, respectively, for 19,882 and, 20,362 reflections (Fobs &gt; 2.0 sigma). Standard deviations for, stereochemical parameters are 0.018 and 0.022 A for bond distances, 0.030, and 0.038 A for angle distances, and 0.035 and 0.070 A for planar 1-4, distances. The newly refined normal structure shows improvement over the, original structure of Blake and Swan (Blake, C. C. F., and Swan, I. D. A., (1971) J. Mol. Biol. 61, 217-224) in stereochemistry and in the, conformation of the loop regions. Residues Arg-103, Thr-123, Asn-124, and, Pro-125 have now been resolved, and residues 1-9 and 126-127 have been, modeled with the aid of simulated annealing refinement. The functional, form of transthyretin is a tetramer, having a cylindrical cavity which, will bind thyroxine and an exterior binding site for the complex of, retinol with retinol-binding protein. The monomer is a beta barrel, flattened to become more like a sandwich with residue 30 in the interior., The methionyl for valyl substitution forces the beta sheets of the monomer, as much as 1 A apart, resulting in a distortion of the thyroxine-binding, cavity, in agreement with the independent observations that the Met-30, variant has low affinity for thyroxine.

==Disease==
Known diseases associated with this structure: Amyloid neuropathy, familial, several allelic types OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=176300 176300]], Amyloidosis, senile systemic OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=176300 176300]], Carpal tunnel syndrome, familial OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=176300 176300]], Dystransthyretinemic hyperthyroxinemia OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=176300 176300]]

==About this Structure==
1TTC is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens]. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=1TTC OCA]. 

==Reference==
The x-ray crystal structure refinements of normal human transthyretin and the amyloidogenic Val-30--&gt;Met variant to 1.7-A resolution., Hamilton JA, Steinrauf LK, Braden BC, Liepnieks J, Benson MD, Holmgren G, Sandgren O, Steen L, J Biol Chem. 1993 Feb 5;268(4):2416-24. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=8428915 8428915]
[[Category: Homo sapiens]]
[[Category: Single protein]]
[[Category: Braden, B.C.]]
[[Category: Hamilton, J.A.]]
[[Category: Steinrauf, L.K.]]
[[Category: transport(thyroxine)]]

''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Mon Nov 12 19:27:47 2007''