Spectrin repeat

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Spectrin repeat
PDB 1aj3 EBI.jpg
Structure of the spectrin repeat: a left-handed antiparallel triple-helical coiled-coil. [1]
Identifiers
SymbolSpectrin
Pfam PF00435
Pfam clan CL0743
ECOD 604.1.1
InterPro IPR002017
PROSITE PDOC50083
SCOP2 1aj3 / SCOPe / SUPFAM
CDD cd00176
Available protein structures:
Pfam   structures / ECOD  
PDB RCSB PDB; PDBe; PDBj
PDBsum structure summary

Spectrin repeats [2] are found in several proteins involved in cytoskeletal structure. These include spectrin, alpha-actinin, dystrophin and more recently the plakin family. The spectrin repeat forms a three-helix bundle. These conform to the rules of the heptad repeat. Spectrin repeats give rise to linear proteins. This however may be due to sample bias in which linear and rigid structures are more amenable to crystallization. There are hints however, that some proteins harbouring spectrin repeats may also be flexible. This is most likely due to specifically evolved functional purposes.

Contents

Human proteins containing this domain

ACTN1; ACTN2; ACTN3; ACTN4; AKAP6; SYNE3; CATX-15; DMD; DRP2; DST; KALRN; MACF1; MCF2L; SPTA1; SPTAN1; SPTB; SPTBN1; SPTBN2; SPTBN4; SPTBN5; SYNE1; SYNE2; TRIO; UTRN;

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References

  1. Pascual J, Pfuhl M, Walther D, Saraste M, Nilges M (October 1997). "Solution structure of the spectrin repeat: a left-handed antiparallel triple-helical coiled-coil". J. Mol. Biol. 273 (3): 740–51. doi:10.1006/jmbi.1997.1344. PMID   9356261.
  2. Harrison SC, Yan Y, Winograd E, Viel A, Cronin T, Branton D (1993). "Crystal structure of the repetitive segments of spectrin". Science. 262 (5142): 2027–2030. doi:10.1126/science.8266097. PMID   8266097.

Further reading