1owa
From Proteopedia
Solution Structural Studies on Human Erythrocyte Alpha Spectrin N Terminal Tetramerization Domain
Contents |
Overview
We have determined the solution NMR structure of a recombinant peptide that consists of the first 156 residues of erythroid alpha-spectrin. The first 20 residues preceding the first helix (helix C') are in a disordered conformation. The subsequent three helices (helices A1, B1, and C1) form a triple helical bundle structural domain that is similar, but not identical, to previously published structures for spectrin from Drosophila and chicken brain. Paramagnetic spin label-induced NMR resonance broadening shows that helix C', the partial domain involved in alpha- and beta-spectrin association, exhibits little interaction with the structural domain. Surprisingly, helix C' is connected to helix A1 of the structural domain by a segment of 7 residues (the junction region) that exhibits a flexible disordered conformation, in contrast to the predicted rigid helical structure. We suggest that the flexibility of this particular junction region may play an important role in modulating the association affinity of alpha- and beta-spectrin at the tetramerization site of different isoforms, such as erythroid spectrin and brain spectrin. These findings may provide insight for explaining various physiological and pathological conditions that are a consequence of varying alpha- and beta-subunit self-association affinities in their formation of the various spectrin tetramers.
Disease
Known disease associated with this structure: Elliptocytosis-2 OMIM:[182860], Pyropoikilocytosis OMIM:[182860], Spherocytosis, recessive OMIM:[182860]
About this Structure
1OWA is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Solution structural studies on human erythrocyte alpha-spectrin tetramerization site., Park S, Caffrey MS, Johnson ME, Fung LW, J Biol Chem. 2003 Jun 13;278(24):21837-44. Epub 2003 Apr 1. PMID:12672815 Page seeded by OCA on Sat May 3 04:21:13 2008
