We determined the isoforms of tropomyosin expressed and the level of tropomyosin phosphorylation in donor, end-stage failing and hypertrophic obstructive cardiomyopathy samples of human heart muscle. Western blots and isoform-specific antibodies showed that α-tropomyosin was the only significant isoform expressed and that tropomyosin was 25-30 % phosphorylated at serine 283. Mass spectrometry confirmed directly that α-tropomyosin made up over 95 % of tropomyosin but also indicated the presence of up to 4 % κ-tropomyosin and much smaller amounts of β-, γ- and smooth β-tropomyosin and about 26 % phosphorylation. Neither the isoform distribution nor the level of phosphorylation changed significantly in the pathological heart muscle samples. © 2013 Springer Science+Business Media Dordrecht.
Marston, S. B., Copeland, O., Messer, A. E., Mcnamara, E., Nowak, K., Zampronio, C. G., & Ward, D. G. (2013). Tropomyosin isoform expression and phosphorylation in the human heart in health and disease. Journal of Muscle Research and Cell Motility, 34(3-4), 189-197. https://doi.org/10.1007/s10974-013-9347-8