Phenotypes associated with this allele
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| Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Myh6tm2Jse mutation
(0 available);
any
Myh6 mutation
(206 available)
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growth/size/body
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• heart ventricles show upregulation of hypertrophy markers shortly before death
• hearts show hypertrophy of all cardiac chambers at 1 week of age
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mortality/aging
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• 100% of mice die within 9 days after birth
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cardiovascular system
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• myocyte disarray at 1 week of age
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• hearts show areas in the myocardium with calcifications
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• atria are enlarged in 1 week old mice
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• heart ventricles show upregulation of hypertrophy markers shortly before death
• hearts show hypertrophy of all cardiac chambers at 1 week of age
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• hearts show patches of dying myocardial cells
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cellular
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• hearts show patches of dying myocardial cells
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muscle
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• myocyte disarray at 1 week of age
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• hearts show areas in the myocardium with calcifications
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• hearts show patches of dying myocardial cells
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Allelic
Composition |
Myh6tm2Jse/Myh6+
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Genetic
Background |
involves: 129 |
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| Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Myh6tm2Jse mutation
(0 available);
any
Myh6 mutation
(206 available)
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cardiovascular system
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• myofiber disarray at 26 weeks of age
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• progressive concentric hypertrophy
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• left ventricular wall thickness is more than 20% greater than in wild-type mice at 26 weeks of age
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• interstitial fibrosis at 26 weeks of age
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• % ejection fraction is increased
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• echocardiography indicates increased left ventricular anterior wall thickness, left ventricular posterior wall thickness, and increased % ejection fraction
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growth/size/body
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• progressive concentric hypertrophy
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muscle
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• myofiber disarray at 26 weeks of age
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• % ejection fraction is increased
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cellular
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• interstitial fibrosis at 26 weeks of age
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Allelic
Composition |
Myh6tm2Jse/Myh6+
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Genetic
Background |
involves: 129S1/Sv |
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| Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Myh6tm2Jse mutation
(0 available);
any
Myh6 mutation
(206 available)
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cardiovascular system
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• slight myocyte disarray is noticeable in tissue from apex of mutant hearts at 10-20 weeks of age
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• mutants show marked differences in cross-bridge kinetics of isolated myosin and skinned strips of myocardium
• maximal velocity (V) of regulated thin filament (RTF) in an in vitro motility assay is not changed compared to wild-type
• myosin concentration at half-maximal VRTF is not different from wild-type
• characteristic frequency for oscillatory work production in skinned strips is 18% higher in mutants vs wild-type
• calcium sensitivity for isometric tension in skinned strips (pCa50=5.82) is significantly enhanced compared to wild-type (pCa50=5.58)
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muscle
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• slight myocyte disarray is noticeable in tissue from apex of mutant hearts at 10-20 weeks of age
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homeostasis/metabolism
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| Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Myh6tm1.1Jpsc mutation
(0 available);
any
Myh6 mutation
(206 available)
Myh6tm2Jse mutation
(0 available);
any
Myh6 mutation
(206 available)
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mortality/aging
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• mice live to adulthood but die prematurely at a mean age of 62 +/- 8 weeks
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cardiovascular system
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• heart myocytes are enlarged
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• heart-to-body weight ratio is increased compared to wild-type mice or Myh6tm1.1Jpsc heterozygotes
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• hypertrophy of hearts rapidly progresses and exceeds the wall thickness of Myh6tm1.1Jpsc heterozygotes by more than 50% at 26 weeks of age
• markers of hypertrophy are elevated already at 6-8 weeks of age
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• left ventricular wall thickness is almost doubled compared to Myh6tm1.1Jpsc heterozygotes
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• myocardium shows massive fibrosis that is detectable at 10 weeks of age and progresses over time
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• left atrial tissue generates only 46% of the force produced by Myh6tm1.1Jpsc heterozygous tissue and the speed of force generation and speed of force decay are reduced
• beta-adrenergic stimulation fails to enhance slow contraction and relaxation of hearts indicating a loss of cardiac reserve
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• ventricular stroke volume is depressed in 26 week old mice
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• end-diastolic volumes are low and ventricular stroke volume is depressed in 26 week old mice and left ventricles show depressed velocities of pressure rise and low maximal left ventricular pressures at 6-8 weeks of age, indicating impaired systolic function
• however, fractional shortening is conserved at 26 weeks of age
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• left ventricular relaxation is impaired in 6-8 week old mice, with reduced left ventricular end-diastolic volume and reduced maximum speed of pressure decay, indicating diastolic dysfunction before the development of hypertrophy and fibrosis
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• echocardiography indicates increased left ventricular anterior wall thickness and posterior wall thickness in systole and in diastole, decreased left ventricle diameter, and decreased stroke volume
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muscle
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• heart myocytes are enlarged
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• end-diastolic volumes are low and ventricular stroke volume is depressed in 26 week old mice and left ventricles show depressed velocities of pressure rise and low maximal left ventricular pressures at 6-8 weeks of age, indicating impaired systolic function
• however, fractional shortening is conserved at 26 weeks of age
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• left ventricular relaxation is impaired in 6-8 week old mice, with reduced left ventricular end-diastolic volume and reduced maximum speed of pressure decay, indicating diastolic dysfunction before the development of hypertrophy and fibrosis
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growth/size/body
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• heart-to-body weight ratio is increased compared to wild-type mice or Myh6tm1.1Jpsc heterozygotes
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• hypertrophy of hearts rapidly progresses and exceeds the wall thickness of Myh6tm1.1Jpsc heterozygotes by more than 50% at 26 weeks of age
• markers of hypertrophy are elevated already at 6-8 weeks of age
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Analysis Tools