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Blood, 15 June 2008, Vol. 111, No. 12, pp. 5712-5720. Prepublished online as a Blood First Edition Paper on January 24, 2008; DOI 10.1182/blood-2007-11-122457. This Article Full Text Full Text (PDF) Supplemental Figures All Versions of this Article: blood-2007-11-122457v1 111/12/5712    most recent Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Rights and Permissions Citing Articles Citing Articles via CrossRef Google Scholar Articles by Gaetani, M. Articles by Speicher, D. W. PubMed PubMed Citation Articles by Gaetani, M. Articles by Speicher, D. W. Related Collections Red Cells Related Article in Blood Online Social Bookmarking                   What's this?  Previous Article  |  Table of Contents  |  Next Article  RED CELLS Structural and functional effects of hereditary hemolytic anemia-associated point mutations in the alpha spectrin tetramer site Massimiliano Gaetani1, Sara Mootien2, Sandra Harper1, Patrick G. Gallagher2, and David W. Speicher1 1 The Wistar Institute, Philadelphia, PA; and 2 Yale University School of Medicine, New Haven, CT The most common hereditary elliptocytosis (HE) and hereditary pyropoikilocytosis (HPP) mutations are -spectrin missense mutations in the dimer-tetramer self-association site. In this study, we systematically compared structural and functional properties of the 14 known HE/HPP mutations located in the -spectrin tetramer binding site. All mutant -spectrin recombinant peptides were well folded, stable structures, with only the R34W mutant exhibiting a slight structural destabilization. In contrast, binding affinities measured by isothermal titration calorimetry were greatly variable, ranging from no detectable binding observed for I24S, R28C, R28H, R28S, and R45S to approximately wild-type binding for R34W and K48R. Binding affinities for the other 7 mutants were reduced by approximately 10- to 100-fold relative to wild-type binding. Some sites, such as R28, were hot spots that were very sensitive to even relatively conservative substitutions, whereas other sites were only moderately perturbed by nonconservative substitutions. The R34W and K48R mutations were particularly intriguing mutations that apparently either destabilize tetramers through mechanisms not probed by the univalent tetramer binding assay or represent polymorphisms rather than the pathogenic mutations responsible for observed clinical symptoms. All 0 HE/HPP mutations studied here appear to exert their destabilizing effects through molecular recognition rather than structural mechanisms. CiteULike    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this? Related Article in Blood Online: Mechanisms of elliptocytosis: significant spectrin substitutions Anthony J. Baines Blood 2008 111: 5417. [Full Text] [PDF]

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