1tz5: Difference between revisions
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==[pNPY19-23]-hPP bound to DPC Micelles== | ==[pNPY19-23]-hPP bound to DPC Micelles== | ||
<StructureSection load='1tz5' size='340' side='right' caption='[[1tz5]], [[NMR_Ensembles_of_Models | 20 NMR models]]' scene=''> | <StructureSection load='1tz5' size='340' side='right'caption='[[1tz5]], [[NMR_Ensembles_of_Models | 20 NMR models]]' scene=''> | ||
== Structural highlights == | == Structural highlights == | ||
<table><tr><td colspan='2'>[[1tz5]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Human Human]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1TZ5 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1TZ5 FirstGlance]. <br> | <table><tr><td colspan='2'>[[1tz5]] is a 1 chain structure with sequence from [http://en.wikipedia.org/wiki/Human Human]. Full experimental information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1TZ5 OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1TZ5 FirstGlance]. <br> | ||
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</StructureSection> | </StructureSection> | ||
[[Category: Human]] | [[Category: Human]] | ||
[[Category: Large Structures]] | |||
[[Category: Aguilar, M I]] | [[Category: Aguilar, M I]] | ||
[[Category: Beck-Sickinger, A G]] | [[Category: Beck-Sickinger, A G]] |
Revision as of 17:17, 25 December 2019
[pNPY19-23]-hPP bound to DPC Micelles[pNPY19-23]-hPP bound to DPC Micelles
Structural highlights
Function[PAHO_HUMAN] Pancreatic hormone is synthesized in pancreatic islets of Langerhans and acts as a regulator of pancreatic and gastrointestinal functions. The physiological role for the icosapeptide has not yet been elucidated. Evolutionary Conservation![]() Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedNeuropeptide Y (NPY) and the pancreatic polypeptide (PP) are members of the neuropeptide Y family of hormones. They bind to the Y receptors with very different affinities: Whereas PP is highly selective for the Y(4) receptor, NPY displays highest affinites for Y(1), Y(2), and Y(5) receptor subtypes. Introducing the NPY segment 19-23 into PP leads to an increase in affinity at the Y(1) and Y(2) receptor subtypes whereas the exchange of this segment from PP into NPY leads to a large decrease in affinity at all receptor subtypes. PP displays a very stable structure in solution, with the N terminus being back-folded onto the C-terminal alpha-helix (the so-called PP-fold). The helix of NPY is less stable and the N terminus is freely diffusing in solution. The exchange of this segment, however, does not alter the PP-fold propensities of the chimeric peptides in solution. The structures of the phospholipid micelle-bound peptides serving to mimic the membrane-bound species display segregation into a more flexible N-terminal region and a well-defined alpha-helical region. The introduction of the [19-23]-pNPY segment into hPP leads to an N-terminal extension of the alpha-helix, now starting at Pro(14) instead of Met(17). In contrast, a truncated helix is observed in [(19)(-)(23)hPP]-pNPY, starting at Leu(17) instead of Ala(14). All peptides display moderate binding affinities to neutral membranes (K(assoc) in the range of 1.7 to 6.8 x 10(4) mol(-)(1) as determined by surface plasmon resonance) with the differences in binding being most probably related to the exchange of Arg-19 (pNPY) by Glu-23 (hPP). Differences in receptor binding properties between the chimeras and their parental peptides are therefore most likely due to changes in the conformation of the micelle-bound peptides. Strongly altered receptor binding properties in PP and NPY chimeras are accompanied by changes in structure and membrane binding.,Lerch M, Kamimori H, Folkers G, Aguilar MI, Beck-Sickinger AG, Zerbe O Biochemistry. 2005 Jun 28;44(25):9255-64. PMID:15966750[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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