Skip to main content
Log in

Expression of tropomyosin-κ induces dilated cardiomyopathy and depresses cardiac myofilament tension by mechanisms involving cross-bridge dependent activation and altered tropomyosin phosphorylation

  • Original Paper
  • Published:
Journal of Muscle Research and Cell Motility Aims and scope Submit manuscript

Abstract

Tropomyosin-kappa (TPM1-κ) is a newly discovered tropomyosin (TM) isoform that is exclusively expressed in the human heart and generated by an alternative splicing of the α-TM gene. We reported that TPM1-κ expression was increased in the hearts of patients with chronic dilated cardiomyopathy (DCM). To increase our understanding of the significance of this shift in isoform population, we generated transgenic (TG) mice expressing TPM1-κ in the cardiac compartment where TPM1-κ replaces 90% of the native TM. We previously showed that there was a significant inhibition of the ability of strongly bound cross-bridges to induce activation of TG myofilaments (Rajan et al., Circulation 121:410–418, 2010). Here, we compared the force–Ca2+ relations in detergent extracted (skinned) fiber bundles isolated from non-transgenic (NTG) and TG-TPM1-κ hearts at two sarcomere lengths (SLs). Our data demonstrated a significant decrease in the Ca2+ sensitivity of the myofilaments from TG-TPM1-κ hearts with no change in the maximum developed tension, length-dependent activation, and the ratio of ATPase rate to tension. There was also no difference in the affinity and cooperativity of Ca2+-binding to troponin in thin filaments reconstituted with either TPM1-κ or α-TM. We also compared protein phosphorylation in NTG and TG-TPM1-κ myofilaments. There was a decrease in the total phosphorylation of TPM1-κ compared to α-TM, but no significant change in other major sarcomeric proteins. Our results identify a novel mode of myofilament desensitization to Ca2+ associated with a DCM linked switch in TM isoform population.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4

Similar content being viewed by others

References

  • Davis JP, Norman C, Kobayashi T, Solaro RJ, Swartz DR, Tikunova SB (2007) Effects of thin and thick filament proteins on calcium binding and exchange with cardiac troponin C. Biophys J 92(9):3195–3206

    Article  CAS  PubMed  Google Scholar 

  • de Tombe PP, Stienen GJ (1995) Protein kinase A does not alter economy of force maintenance in skinned rat cardiac trabeculae. Circ Res 76(5):734–741

    PubMed  Google Scholar 

  • de Tombe PP, Stienen GJ (2007) Impact of temperature on cross-bridge cycling kinetics in rat myocardium. J Physiol 584(Pt 2):591–600

    Article  PubMed  Google Scholar 

  • Denz CR, Narshi A, Zajdel RW, Dube DK (2004) Expression of a novel cardiac-specific tropomyosin isoform in humans. Biochem Biophys Res Commun 320:1291–1297

    Article  CAS  PubMed  Google Scholar 

  • Fabiato A (1988) Computer programs for calculating total from specified free or free from specified total ionic concentrations in aqueous solutions containing multiple metals and ligands. Methods Enzymol 157:378–417

    Article  CAS  PubMed  Google Scholar 

  • Heeley DH, Watson MH, Mak AS, Dubord P, Smillie LB (1989) Effect of phosphorylation on the interaction and functional properties of rabbit striated muscle αα-tropomyosin. J Biol Chem 264(5):2424–2430

    CAS  PubMed  Google Scholar 

  • Jagatheesan G, Rajan S, Petrashevskaya N, Schwartz A, Boivin G, Arteaga GM, Solaro RJ, Liggett SB, Wieczorek DF (2007) Rescue of tropomyosin-induced familial hypertrophic cardiomyopathy mice by transgenesis. Am J Physiol Heart Circ Physiol 293(2):H949–H958

    Article  CAS  PubMed  Google Scholar 

  • Kobayashi T, Solaro RJ (2006) Increased Ca2+ affinity of cardiac thin filaments reconstituted with cardiomyopathy-related mutant cardiac troponin I. J Biol Chem 281(19):13471–13477

    Article  CAS  PubMed  Google Scholar 

  • Kobayashi T, Zhao X, Wade R, Collins JH (1999) Ca-dependent interaction of the inhibitory region of troponin I with acidic residues in the N-terminal domain of troponin C. Biochim Biophys Acta 1430:214–221

    Article  CAS  PubMed  Google Scholar 

  • Lakdawala NK, Dellefave L, Redwood CS, Sparks E, Cirino AL, Depalma S, Colan SD, Funke B, Zimmerman RS, Robinson P, Watkins H, Seidman CE, Seidman JG, McNally EM, Ho C (2010) Familial dilated cardiomyopathy caused by an alpha-tropomyosin mutation. J Am Coll Cardiol 55:320–329

    Article  CAS  PubMed  Google Scholar 

  • Lehrer SS, Golistina NL, Geeves MA (1997) Actin-tropomyosin activation of myosin subfragment 1 ATPase and thin filament cooperativity. The role of tropomyosin flexibility and end-to-end interactions. Biochemistry 36(44):13449–13454

    Article  CAS  PubMed  Google Scholar 

  • Millar NC, Homsher E (1990) The effect of phosphate and calcium on force generation in glycerinated rabbit skeletal muscle fibers. A steady-state and transient kinetic study. J Biol Chem 265:20234–20240

    CAS  PubMed  Google Scholar 

  • Monteiro PB, Lataro RC, Ferro JA, de Reinach FC (1994) Functional alpha-tropomyosin produced in Escherichia coli A dipeptide extension can substitute the amino-terminal acetyl group. J Biol Chem 269(14):10461–10466

    CAS  PubMed  Google Scholar 

  • Muthuchamy M, Grupp IL, Grupp G, O’Toole BA, Kier AB, Boivin GP, Neumann J, Wieczorek DF (1995) Molecular and physiological effects of overexpressing striated muscle beta-tropomyosin in the adult murine heart. J Biol Chem 270(51):30593–30603

    Article  CAS  PubMed  Google Scholar 

  • Olson TM, Kishimoto NY, Whitby FG, Michels VV (2001) Mutations that alter the surface charge of alpha-tropomyosin are associated with dilated cardiomyopathy. J Mol Cell Cardiol 33:723–732

    Article  CAS  PubMed  Google Scholar 

  • Patton C, Thompson S, Epel D (2004) Some precautions in using chelators to buffer metals in biological solutions. Cell Calcium 35:427–431

    Article  CAS  PubMed  Google Scholar 

  • Pieples K, Arteaga G, Solaro RJ, Grupp I, Lorenz JN, Boivin GP, Jagatheesan G, Labitzke E, de Tombe PP, Konhilas JP, Irving TC, Wieczorek DF (2002) Tropomyosin 3 expression leads to hypercontractility and attenuates myofilament length-dependent Ca2+ activation. Am J Physiol Heart Circ Physiol 283:H1344–H1353

    CAS  PubMed  Google Scholar 

  • Rajan S, Ahmed RPH, Jagatheesan G, Petrashevskaya N, Boivin GP, Urboniene D, Arteaga GM, Wolska BM, Solaro RJ, Liggett SB, Wieczorek DF (2007) Dilated cardiomyopathy mutant tropomyosin mice develop cardiac dysfunction with significantly decreased fractional shortening and myofilament calcium sensitivity. Circ Res 101(2):205–214. Erratum in: Circ Res. 2007 Sep 14;101(6):e80, 2007

    Google Scholar 

  • Rajan S, Jagatheesan G, Karam CN, Alves ML, Bodi I, Schwartz A, Bulcao CF, D’Souza KM, Akhter SA, Boivin GP, Dube DK, Petrashevskaya N, Herr AB, Hullin R, Liggett SB, Wolska BM, Solaro RJ, Wieczorek DF (2010) Molecular and functional characterization of a novel cardiac-specific human tropomyosin isoform. Circulation 121:410–418

    Article  CAS  PubMed  Google Scholar 

  • Rao VS, Marongelli EN, Guilford WH (2009) Phosphorylation of tropomyosin extends cooperative binding of myosin beyond a single regulatory unit. Cell Motil Cytosckelet 66(1):10–23

    Article  CAS  Google Scholar 

  • Robinson P, Griffiths PJ, Watkins H, Redwood CS (2007) Dilated and hyperthrophic cardiomyopathy mutations in troponin and α-tropomyosin have opposing effects on the calcium affinity of cardiac thin filaments. Circ Res 101:1266–1273

    Article  CAS  PubMed  Google Scholar 

  • Solaro RJ (2009) CK-1827452, a sarcomere-directed cardiac myosin activator for acute and chronic heart disease. IDrugs 12:243–251

    CAS  PubMed  Google Scholar 

  • Solaro RJ, Lee JA, Kentich JC, Allen DG (1988) Effects of acidosis on ventricular muscle from adult and neonatal rats. Circ Res 63(4):779–787

    CAS  PubMed  Google Scholar 

  • Sumandea MP, Pyle WG, Kobayashi T, de Tombe PP, Solaro RJ (2003) Identification of a functionally critical protein kinase C phosphorylation residue of cardiac troponin T. J Biol Chem 278:35135–35144

    Article  CAS  PubMed  Google Scholar 

  • Sun YB, Irving M (2010) The molecular basis of the steep force-calcium relation in heart muscle. J Mol Cell Cardiol 48:859–865

    Article  CAS  PubMed  Google Scholar 

  • Trybus KM, Taylor EW (1980) Kinetic studies of the cooperative binding of subfragment 1 to regulated actin. Proc Natl Acad Sci USA 77:7209–7213

    Article  CAS  PubMed  Google Scholar 

  • Vahebi S, Ota A, Li M, Warren CM, de Tombe PP, Wang Y, Solaro RJ (2007) p38-MAPK induced dephosphorylation of alpha-tropomyosin is associated with depression of myocardial sarcomeric tension and ATPase activity. Circ Res 100(3):408–415

    Article  CAS  PubMed  Google Scholar 

  • VanBuren P, Palmer BM (2010) Cooperative activation of the cardiac myofilament: the pivotal role of tropomyosin. Circulation 121:351–353

    Article  PubMed  Google Scholar 

  • Wannenburg T, Janssen PM, de Tombe PP (1997) The Frank-Starling mechanism is not mediated by changes in rate of cross-bridge detachment. Am J Physiol 273(5 Pt 2):H2428–H2435

    CAS  PubMed  Google Scholar 

  • Warren CM, Arteaga GM, Rajan S, Ahmed RPH, Wieczorek DF, Solaro RJ (2008) Use of 2-D DIGE analysis reveals altered phosphorylation in a tropomyosin mutant (Glu54Lys) linked to dilated cardiomyopathy. Proteomics 8:100–106

    Article  CAS  PubMed  Google Scholar 

  • Wolska BM, Keller RS, Evans CC, Palmiter KA, Phillips RM, Muthuchamy M, Oehlenschlager J, Wieczorek DF, de Tombe PP, Solaro RJ (1999) Correlation between myofilaments response to Ca2+ and altered dynamics of contraction and relaxation in transgenic cardiac cells than express beta-tropomyosin. Circ Res 84:745–751

    CAS  PubMed  Google Scholar 

  • Yuan C, Sheng Q, Tang H, Li Y, Zeng R, Solaro RJ (2008) Quantitative comparison of sarcomeric phosphoproteomes of neonatal and adult rat hearts. Am J Physiol Heart Circ Physiol 295:H647–H656

    Article  CAS  PubMed  Google Scholar 

Download references

Acknowledgments

The authors would like to thank both Dr. Tomoyoshi Kobayashi for his help with the TnC binding measurements and Bindiya G. Patel for her assistance with the 2D-DIGE experiments. This work was supported by American Heart Association-Midwest Pre-Doctoral Fellowship (CNK) and by NIH Grants PO1 HL062426 (RJS, PdeT), RO1 HL022231 (RJS), RO1 HL081680, and RO1 HL071952 (DFW).

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to R. John Solaro.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Karam, C.N., Warren, C.M., Rajan, S. et al. Expression of tropomyosin-κ induces dilated cardiomyopathy and depresses cardiac myofilament tension by mechanisms involving cross-bridge dependent activation and altered tropomyosin phosphorylation. J Muscle Res Cell Motil 31, 315–322 (2011). https://doi.org/10.1007/s10974-010-9237-2

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10974-010-9237-2

Keywords

Navigation