Phenotype Image Detail

Image

Caption

Ultrastructural analysis of the left ventricle of Tg(Myh6-Myl2*)21Rbns/0 mice. Shown are electron micrographs from sections taken of adult line 21 hearts. A, longitudinal section from a 4.5 month old nontransgenic (NTG) mouse. The myocytes show normal sarcomeric organization with rows of mitochondria and regular invaginations of the sarcolemma at the intercalated disc (ID). Perivascular areas contain some collagen fibers (arrowhead). V, blood vessel. B: A section from a 4.5 month old Tg(Myh6-Myl2*)21Rbns/0 mouse. Wide interstitial areas with numerous processes (probably fibroblasts) are apparent. A degenerating myocyte is adjacent to two normal cells. The degenerating myocyte has no sarcomeric organization, few mitochondria, and little sarcoplasmic reticulum. The visible intercalated disc (ID) appears to be highly convoluted. Several myelin figures (+) are present, not only in the degenerated cell but also in the surrounding myocytes, suggesting that these cells are in early stages of degeneration as well. The interstitium contains collagen and basal lamina-like material (arrowheads). V, blood vessel. C and D, high magnification of myocytes from mutant mice in various stages of degeneration. C, a small portion of this cell is completely devoid of sarcomeric organization and contains scattered electron-dense material. Other parts of the myocyte show irregular accumulations of Z-band-like material (arrows), distended T-tubules, and small myelin figures (+). Note the collagen fibers in the interstitium (arrowheads). D, a fragment of a partially degenerated myocyte showing normal looking sarcomeres adjacent to an area with scattered amorphous material of various electron density, remnants of sarcoplasmic reticulum, and no mitochondria. The interstitium contains collagen (arrowheads). The abnormalities are representative of multiple grids obtained from sections derived from 10-week old mice.

Copyright

This image is from Sanbe A, J Biol Chem 1999 Jul 23;274(30):21085-94 and is displayed with the permission of the American Society for Biochemistry and Molecular Biology who owns the Copyright. Full text from JBC. J:114298

Associated Alleles

Symbol	Name
Tg(Myh6-Myl2*)21Rbns	transgene insertion 21, Jeffrey Robbins

Associated Genotypes

Allelic Composition	Genetic Background
Tg(Myh6-Myl2*)21Rbns/0	Not Specified