{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,10]],"date-time":"2026-06-10T14:31:54Z","timestamp":1781101914883,"version":"3.54.1"},"reference-count":0,"publisher":"National Academy of Sciences","issue":"23","content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[1987,12]]},"abstract":"<jats:p>2A new calcitonin analogue, model calcitonin III (MCt-III), has been synthesized, and its biological and physical characteristics have been studied. This analogue has an idealized alpha-helix from residue 8-22 with glutamate at position 15 interrupting an otherwise continuous surface of aliphatic side chains (those of leucine residues) on the hydrophobic face of the helix. MCt-III differs from a previous model, MCt-II, only by the substitution Leu15----Glu and is here compared with salmon calcitonin I (sCt-I) and MCt-II to elucidate further the role of the putative amphiphilic alpha-helix in determining biological and physical properties of the hormone. MCt-III shows physical properties intermediate between those of sCt-I and MCt-II, demonstrating the influence of appropriately positioned single residues on properties of amphiphilic structures. In our two biological assays, a brain-binding assay and an in vivo hypocalcemic assay, MCt-III reproduces the sigmoidal dose-response curves of sCt-I; this contrasts with the behavior of MCt-II, which demonstrated unusual dose-response curves in these two assays. MCt-III is almost three times more potent than sCt-I in our hypocalcemic assay; this activity groups MCt-III among the most potent known analogues of sCt-I.<\/jats:p>","DOI":"10.1073\/pnas.84.23.8340","type":"journal-article","created":{"date-parts":[[2006,5,31]],"date-time":"2006-05-31T06:29:20Z","timestamp":1149056960000},"page":"8340-8344","update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":25,"title":["Biological and physical properties of a model calcitonin containing a glutamate residue interrupting the hydrophobic face of the idealized amphiphilic alpha-helical region."],"prefix":"10.1073","volume":"84","author":[{"suffix":"3rd","given":"F R","family":"Green","sequence":"first","affiliation":[{"name":"Laboratory of Bioorganic Chemistry and Biochemistry, Rockefeller University, New York, NY 10021."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"B","family":"Lynch","sequence":"additional","affiliation":[{"name":"Laboratory of Bioorganic Chemistry and Biochemistry, Rockefeller University, New York, NY 10021."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"E T","family":"Kaiser","sequence":"additional","affiliation":[{"name":"Laboratory of Bioorganic Chemistry and Biochemistry, Rockefeller University, New York, NY 10021."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[1987,12]]},"container-title":["Proceedings of the National Academy of Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pnas.org\/doi\/pdf\/10.1073\/pnas.84.23.8340","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,4,13]],"date-time":"2022-04-13T12:10:53Z","timestamp":1649851853000},"score":1,"resource":{"primary":{"URL":"https:\/\/pnas.org\/doi\/full\/10.1073\/pnas.84.23.8340"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1987,12]]},"references-count":0,"journal-issue":{"issue":"23","published-print":{"date-parts":[[1987,12]]}},"alternative-id":["10.1073\/pnas.84.23.8340"],"URL":"https:\/\/doi.org\/10.1073\/pnas.84.23.8340","relation":{},"ISSN":["0027-8424","1091-6490"],"issn-type":[{"value":"0027-8424","type":"print"},{"value":"1091-6490","type":"electronic"}],"subject":[],"published":{"date-parts":[[1987,12]]},"assertion":[{"value":"1987-12-01","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}