Abstract
We present a study of intramuscular motion during contraction of skeletal muscle myofibrils. Myofibrillar actin was labeled with fluorescent dye so that the ratio of fluorescently labeled to unlabeled protein was 1:105. Such sparse labeling assured that there was on average only one actin-marker present in the focus at a given time. From the intensity signal in the two orthogonal detection channels, significant fluctuations, similar to fluorescent burst in diffusion-based single-molecule detection schemes, were identified via a threshold algorithm and analyzed with respect to their intensity and polarization. When only rigor complexes were formed, the fluctuations of polarized intensity were characterized by unimodal Gaussian photon distributions. During contraction, in contrast, bimodal Gaussian photon distributions were observed above the rigor background threshold. This suggests that the bimodal Gaussian photon distributions represent pre- and post-power stroke conformations. Clusters of polarized photons indicated an anisotropy decay of single actomyosin motors of ~9s during muscle contraction. This article is part of a Special Issue entitled: 11th European Symposium on Calcium.
| Original language | English |
|---|---|
| Pages (from-to) | 858-866 |
| Number of pages | 9 |
| Journal | Biochimica et Biophysica Acta - Molecular Cell Research |
| Volume | 1813 |
| Issue number | 5 |
| DOIs | |
| State | Published - 1 May 2011 |
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Keywords
- Live skeletal muscle cell
- Molecular orientations
- Polarization dependent fluorescence fluctuations
- Single actomyosin
- Time-dependent photon distributions
Cite this
}
Single actomyosin motor interactions in skeletal muscle. / Földes-Papp, Zeno; Liao, Shih Chu Jeff; Barbieri, Ben; Gryczynski, Karol; Luchowski, Rafal; Gryczynski, Zygmunt; Gryczynski, Ignacy; Borejdo, Julian; You, Tiefeng.
In: Biochimica et Biophysica Acta - Molecular Cell Research, Vol. 1813, No. 5, 01.05.2011, p. 858-866.Research output: Contribution to journal › Article
TY - JOUR
T1 - Single actomyosin motor interactions in skeletal muscle
AU - Földes-Papp, Zeno
AU - Liao, Shih Chu Jeff
AU - Barbieri, Ben
AU - Gryczynski, Karol
AU - Luchowski, Rafal
AU - Gryczynski, Zygmunt
AU - Gryczynski, Ignacy
AU - Borejdo, Julian
AU - You, Tiefeng
PY - 2011/5/1
Y1 - 2011/5/1
N2 - We present a study of intramuscular motion during contraction of skeletal muscle myofibrils. Myofibrillar actin was labeled with fluorescent dye so that the ratio of fluorescently labeled to unlabeled protein was 1:105. Such sparse labeling assured that there was on average only one actin-marker present in the focus at a given time. From the intensity signal in the two orthogonal detection channels, significant fluctuations, similar to fluorescent burst in diffusion-based single-molecule detection schemes, were identified via a threshold algorithm and analyzed with respect to their intensity and polarization. When only rigor complexes were formed, the fluctuations of polarized intensity were characterized by unimodal Gaussian photon distributions. During contraction, in contrast, bimodal Gaussian photon distributions were observed above the rigor background threshold. This suggests that the bimodal Gaussian photon distributions represent pre- and post-power stroke conformations. Clusters of polarized photons indicated an anisotropy decay of single actomyosin motors of ~9s during muscle contraction. This article is part of a Special Issue entitled: 11th European Symposium on Calcium.
AB - We present a study of intramuscular motion during contraction of skeletal muscle myofibrils. Myofibrillar actin was labeled with fluorescent dye so that the ratio of fluorescently labeled to unlabeled protein was 1:105. Such sparse labeling assured that there was on average only one actin-marker present in the focus at a given time. From the intensity signal in the two orthogonal detection channels, significant fluctuations, similar to fluorescent burst in diffusion-based single-molecule detection schemes, were identified via a threshold algorithm and analyzed with respect to their intensity and polarization. When only rigor complexes were formed, the fluctuations of polarized intensity were characterized by unimodal Gaussian photon distributions. During contraction, in contrast, bimodal Gaussian photon distributions were observed above the rigor background threshold. This suggests that the bimodal Gaussian photon distributions represent pre- and post-power stroke conformations. Clusters of polarized photons indicated an anisotropy decay of single actomyosin motors of ~9s during muscle contraction. This article is part of a Special Issue entitled: 11th European Symposium on Calcium.
KW - Live skeletal muscle cell
KW - Molecular orientations
KW - Polarization dependent fluorescence fluctuations
KW - Single actomyosin
KW - Time-dependent photon distributions
UR - http://www.scopus.com/inward/record.url?scp=79955664446&partnerID=8YFLogxK
U2 - 10.1016/j.bbamcr.2011.02.001
DO - 10.1016/j.bbamcr.2011.02.001
M3 - Article
C2 - 21315775
AN - SCOPUS:79955664446
VL - 1813
SP - 858
EP - 866
JO - BBA - Molecular Cell Research
JF - BBA - Molecular Cell Research
SN - 0167-4889
IS - 5
ER -