Investigation of a genetically engineered mutant of barnacle troponin C containing a central helix deletion

L. D. Allhouse, T. Miller, Q. Li, G. Guzman, J. D. Potter, A. Mandveno, C. C. Ashley

Research output: Contribution to journalArticle

2 Scopus citations


To examine the importance of the central α-helix of troponin C (TnC) we have bacterially expressed one of the isoforms of barnacle TnC (BTnC2), BTnCWT, but without the aspartate residue at position 80 in the central helix (BTnC80-). This manipulation is expected to produce an approximately 100°axial rotation of the C-domain with respect to the N-domain, and a net charge change of -1. BTnC80- mutant was able to restore force to TnC-depleted skinned barnacle myofibrillar bundles to a greater extent than wild-type protein (≃170%). Competition experiments between BTnC80- and BTnC2-4-, a mutant lacking both of the calcium-specific sites (sites II and IV), shows that deletion of a single amino acid in the central helix results in a protein with increased affinity for the thin filament and one that is bound preferentially compared to BTnC2-4- when at equimolar concentrations.

Original languageEnglish (US)
Pages (from-to)67-75
Number of pages9
JournalPflugers Archiv European Journal of Physiology
Issue number1-2
StatePublished - Jan 1 1999



  • Barnacle
  • Central-helix troponin C
  • Contraction
  • Mutagenesis

ASJC Scopus subject areas

  • Physiology

Cite this