Crystal Structure of the Repetitive Segments of Spectrin

• Published in: Science (American Association for the Advancement of Science) 1993-12, Vol.262 (5142), p.2027-2030
• Main Authors: Yan, Y., Winograd, E., Viel, A., Cronin, T., Harrison, S. C., Branton, D.
• Format: Article
• Language: English
• Subjects: Acetates; Amino Acid Sequence; Amino acids; Analytical, structural and metabolic biochemistry; Animals; Atoms; Biological and medical sciences; Cellular biology; Crystal structure; Crystalline structure; Crystallization; Crystals; Data collection; Dimers; Diptera; Drosophila; Drosophilidae; Dystrophin; Fundamental and applied biological sciences. Psychology; Glycoproteins; Medical research; Models, Molecular; Molecular biophysics; Molecular Sequence Data; Molecules; Monomers; Physiological aspects; Protein Conformation; Protein structure; Proteins; Spectrin - chemistry; Structure; Structure in molecular biology
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.8266097

The elongated proteins of the spectrin family (dystrophin, α-actinin, and spectrin) contain tandemly repeated segments and form resilient cellular meshworks by cross-linking actin filaments. The structure of one of the repetitive segments of α-spectrin was determined at a 1.8 angstrom resolution. A segment consists of a three-helix bundle. A model of the interface between two tandem segments suggests that hydrophobic interactions between segments may constrain intersegment flexibility. The helix side chain interactions explain how mutations that are known to produce hemolytic anemias disrupt spectrin associations that sustain the integrity of the erythrocyte membrane.