ISSN:
0730-2312
Keywords:
erythrocyte spectrin
;
sequence analysis
;
spectrin structure
;
spectrin homology
;
spectrinlike
;
protein conformation
;
spectrin evolution
;
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
Notes:
Spectrin, the major component of the erythroid membrane skeleton, is a long, asymmetrical rodlike protein that interacts with several other proteins to form a two-dimensional membrane skeleton. Progress in several laboratories over the past few years including substantial partial peptide and nucleotide sequence determination has greatly enhanced our knowledge of the structrual properties of this large molecule (heterodimer = 465,000 daltons). The alpha and beta subunits are homologous with approximately 30% identity. They are aligned in an anti-parallel side-to-side orientation with the amino- and carboxy-termini near opposite physical ends of the molecule. The predominant structural feature elucidated from sequencing this large molecule is the nearly universal occurrence in both subunits of a single type of repetitive structure. The periodicity of this homologous structure is exactly 106 amino acid residues. As many as 36 homologous, but non-identical, repeats exist and comprise more than 90% of the mass of the heterodimer. Each of these repetitive units is folded into a triple-stranded structure that is highly helical. Peptide maps, antibody cross-reactivity, peptide sequence analysis, and more recently nucleic acid sequences have defined several major properties of the erythroid molecule and related proteins in other tissues. Tissue-specific spectrins have the same 106-residue repetitive structure and show sequence homology to erythroid spectrin.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jcb.240300306
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