Three-Dimensional Structure of Vertebrate Muscle Z-Band: The Small-Square Lattice Z-Band in Rat Cardiac Muscle. Burgoyne, T., Morris, E. P., & Luther, P. K. Journal of Molecular Biology, 427(22):3527–3537, November, 2015.
doi  abstract   bibtex   
The Z-band in vertebrate striated muscle crosslinks actin filaments of opposite polarity from adjoining sarcomeres and transmits tension along myofibrils during muscular contraction. It is also the location of a number of proteins involved in signalling and myofibrillogenesis; mutations in these proteins lead to myopathies. Understanding the high-resolution structure of the Z-band will help us understand its role in muscle contraction and the role of these proteins in the function of muscle. The appearance of the Z-band in transverse-section electron micrographs typically resembles a small-square lattice or a basketweave appearance. In longitudinal sections, the Z-band width varies more with muscle type than species: slow skeletal and cardiac muscles have wider Z-bands than fast skeletal muscles. As the Z-band is periodic, Fourier methods have previously been used for three-dimensional structural analysis. To cope with variations in the periodic structure of the Z-band, we have used subtomogram averaging of tomograms of rat cardiac muscle in which subtomograms are extracted and compared and similar ones are averaged. We show that the Z-band comprises four to six layers of links, presumably α-actinin, linking antiparallel overlapping ends of the actin filaments from the adjoining sarcomeres. The reconstruction shows that the terminal 5-7nm of the actin filaments within the Z-band is devoid of any α-actinin links and is likely to be the location of capping protein CapZ.
@article{burgoyne_three-dimensional_2015,
	title = {Three-{Dimensional} {Structure} of {Vertebrate} {Muscle} {Z}-{Band}: {The} {Small}-{Square} {Lattice} {Z}-{Band} in {Rat} {Cardiac} {Muscle}},
	volume = {427},
	issn = {1089-8638},
	shorttitle = {Three-{Dimensional} {Structure} of {Vertebrate} {Muscle} {Z}-{Band}},
	doi = {10.1016/j.jmb.2015.08.018},
	abstract = {The Z-band in vertebrate striated muscle crosslinks actin filaments of opposite polarity from adjoining sarcomeres and transmits tension along myofibrils during muscular contraction. It is also the location of a number of proteins involved in signalling and myofibrillogenesis; mutations in these proteins lead to myopathies. Understanding the high-resolution structure of the Z-band will help us understand its role in muscle contraction and the role of these proteins in the function of muscle. The appearance of the Z-band in transverse-section electron micrographs typically resembles a small-square lattice or a basketweave appearance. In longitudinal sections, the Z-band width varies more with muscle type than species: slow skeletal and cardiac muscles have wider Z-bands than fast skeletal muscles. As the Z-band is periodic, Fourier methods have previously been used for three-dimensional structural analysis. To cope with variations in the periodic structure of the Z-band, we have used subtomogram averaging of tomograms of rat cardiac muscle in which subtomograms are extracted and compared and similar ones are averaged. We show that the Z-band comprises four to six layers of links, presumably α-actinin, linking antiparallel overlapping ends of the actin filaments from the adjoining sarcomeres. The reconstruction shows that the terminal 5-7nm of the actin filaments within the Z-band is devoid of any α-actinin links and is likely to be the location of capping protein CapZ.},
	language = {eng},
	number = {22},
	journal = {Journal of Molecular Biology},
	author = {Burgoyne, Thomas and Morris, Edward P. and Luther, Pradeep K.},
	month = nov,
	year = {2015},
	pmid = {26362007},
	pmcid = {PMC4641244},
	keywords = {Actin Cytoskeleton, Actinin, Animals, Connectin, Cytoskeleton, Microscopy, Electron, Models, Molecular, Muscle Proteins, Myocardium, Rats, Sarcomeres, Z-disc, Z-line, electron microscopy, electron tomography, α-actinin},
	pages = {3527--3537}
}

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