The Postnatal Development of Sarcoplasmic Reticulum Ca2+Transport Activity in Skeletal Muscle of the Rat is Critically Dependent on Thyroid Hormone

Cellular development requires the integrated assembly of intracellular structures into functionally specialized regions supporting overall cellular performance. However, it remains unclear how coordination of organelle interactions contributes to development of functional specificity across cell types. Here, we utilize a subcellular connectomics approach to define the cell-scale reorganization of the mitochondria-organelle interactome across postnatal development in skeletal muscle. We show that while mitochondrial networks are disorganized and loosely associated with the contractile apparatus at birth, contact sites among mitochondria, lipid droplets, and the sarcoplasmic reticulum are highly abundant in neonatal muscles. The maturation process is characterized by a transition to highly organized mitochondrial networks wrapped tightly around the muscle sarcomere but also to less frequent interactions with both lipid droplets and the sarcoplasmic reticulum. These data demonstrate a developmental redesign reflecting a functional shift from muscle cell assembly supported by inter-organelle communication toward a muscle fiber highly specialized for contractile function.

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Thyroid hormone regulates Ca2+-ATPase mRNA levels of sarcoplasmic reticulum during neonatal development of fast skeletal muscle

Molecular and Cellular Endocrinology ◽

10.1016/0303-7207(92)90110-r ◽

1992 ◽

Vol 90 (1) ◽

pp. 125-131 ◽

Cited By ~ 13

Author(s):

Gerard C. van der Linden ◽

Warner S. Simonides ◽

Cornells van Hardeveld

Keyword(s):

Skeletal Muscle ◽

Thyroid Hormone ◽

Sarcoplasmic Reticulum ◽

Mrna Levels ◽

Fast Skeletal Muscle ◽

Neonatal Development

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Ultra-Rapid Freezing of Isolated Skeletal Muscle Fibers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100080316 ◽

1977 ◽

Vol 35 ◽

pp. 576-577

Author(s):

Joachim R. Sommer ◽

Nancy R. Wallace

Keyword(s):

Skeletal Muscle ◽

Sarcoplasmic Reticulum ◽

Granular Material ◽

Nuclear Envelope ◽

Intracellular Calcium ◽

Ruthenium Red ◽

Threshold Concentration ◽

Rapid Freezing ◽

Frog Skeletal Muscle ◽

Electrical Isolation

After Howell (1) had shown that ruthenium red treatment of fixed frog skeletal muscle caused collapse of the intermediate cisternae of the sarcoplasmic reticulum (SR), forming a pentalaminate structure by obi iterating the SR lumen, we demonstrated that the phenomenon involves the entire SR including the nuclear envelope and that it also occurs after treatment with other cations, including calcium (2,3,4).From these observations we have formulated a hypothesis which states that intracellular calcium taken up by the SR at the end of contraction causes the M rete to collapse at a certain threshold concentration as the first step in a subsequent centrifugal zippering of the free SR toward the junctional SR (JSR). This would cause a) bulk transport of SR contents, such as calcium and granular material (4) into the JSR and, b) electrical isolation of the free SR from the JSR.

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Electron Probe Analysis of Muscle

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100054583 ◽

1982 ◽

Vol 40 ◽

pp. 398-401

Author(s):

A. V. Somlyo ◽

H. Shuman ◽

A. P. Somlyo

Keyword(s):

Skeletal Muscle ◽

Smooth Muscle ◽

Sarcoplasmic Reticulum ◽

Resting State ◽

Binding Sites ◽

Electron Probe ◽

Frog Skeletal Muscle ◽

Electron Probe Analysis ◽

Probe Analysis

Electron probe analysis of frozen dried cryosections of frog skeletal muscle, rabbit vascular smooth muscle and of isolated, hyperpermeab1 e rabbit cardiac myocytes has been used to determine the composition of the cytoplasm and organelles in the resting state as well as during contraction. The concentration of elements within the organelles reflects the permeabilities of the organelle membranes to the cytoplasmic ions as well as binding sites. The measurements of [Ca] in the sarcoplasmic reticulum (SR) and mitochondria at rest and during contraction, have direct bearing on their role as release and/or storage sites for Ca in situ.

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