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Expression of a novel combination of fast and slow troponin T isoforms in rabbit extraocular muscles.

Publication ,  Journal Article
Briggs, MM; Jacoby, J; Davidowitz, J; Schachat, FH
Published in: J Muscle Res Cell Motil
June 1988

The properties of extraocular muscles (EOMs) are quite different from those of the trunk and limb. Here we show that there is a novel pattern of troponin T (TnT) expression in EOMs which most likely contributes to the fine control of ocular movement and may reflect their innervation by cranial motoneurons. Three regions of the muscle were analysed to distinguish the TnT isoforms present in the fast singly-innervated fibres from those in the multiply-innervated fibres. More than 95% of the TnT in the singly-innervated fibres is TnT3f, which exhibits the most graded response to changes in calcium concentration during activation (Schachat et al., J. molec. Biol. 198, 551-4). In multiply-innervated fibres, which exhibit tonic contractures, the slow troponin T TnT2s is expressed. While neither TnT3f nor TnT2s is unique to EOM, this pattern is unusual in two respects: first, both TnT3f and TnT2s are minor components of the trunk and limb musculature, and second, most muscles express several fast and both slow TnT species. Although EOM occupies a highly specialized physiological niche, its unusual physiology is not reflected in the presence of new TnT isoforms but in the expression of a different ratio of the known species of TnT.

Duke Scholars

Published In

J Muscle Res Cell Motil

DOI

ISSN

0142-4319

Publication Date

June 1988

Volume

9

Issue

3

Start / End Page

241 / 247

Location

Netherlands

Related Subject Headings

  • Troponin T
  • Troponin
  • Rabbits
  • Physiology
  • Oculomotor Muscles
  • Myosins
  • Animals
  • 0606 Physiology
  • 0601 Biochemistry and Cell Biology
 

Citation

APA
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ICMJE
MLA
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Briggs, M. M., Jacoby, J., Davidowitz, J., & Schachat, F. H. (1988). Expression of a novel combination of fast and slow troponin T isoforms in rabbit extraocular muscles. J Muscle Res Cell Motil, 9(3), 241–247. https://doi.org/10.1007/BF01773894
Briggs, M. M., J. Jacoby, J. Davidowitz, and F. H. Schachat. “Expression of a novel combination of fast and slow troponin T isoforms in rabbit extraocular muscles.J Muscle Res Cell Motil 9, no. 3 (June 1988): 241–47. https://doi.org/10.1007/BF01773894.
Briggs MM, Jacoby J, Davidowitz J, Schachat FH. Expression of a novel combination of fast and slow troponin T isoforms in rabbit extraocular muscles. J Muscle Res Cell Motil. 1988 Jun;9(3):241–7.
Briggs, M. M., et al. “Expression of a novel combination of fast and slow troponin T isoforms in rabbit extraocular muscles.J Muscle Res Cell Motil, vol. 9, no. 3, June 1988, pp. 241–47. Pubmed, doi:10.1007/BF01773894.
Briggs MM, Jacoby J, Davidowitz J, Schachat FH. Expression of a novel combination of fast and slow troponin T isoforms in rabbit extraocular muscles. J Muscle Res Cell Motil. 1988 Jun;9(3):241–247.
Journal cover image

Published In

J Muscle Res Cell Motil

DOI

ISSN

0142-4319

Publication Date

June 1988

Volume

9

Issue

3

Start / End Page

241 / 247

Location

Netherlands

Related Subject Headings

  • Troponin T
  • Troponin
  • Rabbits
  • Physiology
  • Oculomotor Muscles
  • Myosins
  • Animals
  • 0606 Physiology
  • 0601 Biochemistry and Cell Biology