Phenotypes associated with this allele

• Allele Symbol: Tg(Myh6-Actg2)1Jll
• Allele Name: transgene insertion 1, James L Lessard
• Allele ID: MGI:3583998
• Summary: 1 genotype

Jump to	Allelic Composition	Genetic Background	Genotype ID
cx1	Actc1^tm1Jll/Actc1^tm1Jll Tg(Myh6-Actg2)1Jll/0	involves: 129P2/OlaHsd * Black Swiss * FVB/N	MGI:3584000

Genotype
MGI:3584000

cx1

• Allelic Composition: Actc1^tm1Jll/Actc1^tm1Jll; Tg(Myh6-Actg2)1Jll/0
• Genetic Background: involves: 129P2/OlaHsd * Black Swiss * FVB/N

• ♀: phenotype observed in females
• ♂: phenotype observed in males
• N: normal phenotype

Cardiac hypertrophy in Actc1^tm1Jll/Actc1^tm1Jll Tg(Myh6-Actg2)1Jll mice

cardiovascular system

enlarged heart ( J:40165 )

• enlarged, rounded hearts

heart left ventricle hypertrophy ( J:40165 )

• hypertrophy of left ventricular septum and free wall

• thickening of endothelium of the left ventricle with fibrous tissue

• myocyte hypertrophy

dilated heart right ventricle ( J:40165 )

• dilation of right ventricular free wall

cardiac fibrosis ( J:40165 )

• mild

decreased cardiac muscle contractility ( J:40165 , J:107848 )

• hypodynamic; maximal rates of contraction and relaxation are reduced to 40% of the values obtained for controls (J:40165)

• skinned fiber bundles from transgenic mouse hearts ectopically expressing enteric smooth muscle gamma-actin show no differences in maximum Ca²⁺ activated tension or maximum rate of tension redevelopment after a quick release and rapid restretch protocol (J:107848)

• however, transgenic fiber bundles exhibit a reduced sensitivity to Ca²⁺ tension and an increased economy of force development (~35% less ATP hydrolysis) relative to nontransgenic fiber bundles (J:107848)

• reduced sensitivity to Ca²⁺ tension coupled with slower cross-bridge cycling rates are likely to account for the slow rate of contraction noted in the intact heart (J:107848)

decreased heart ventricle muscle contractility ( J:40165 )

• significantly reduced rate of ventricular contraction and relaxation

abnormal cardiac muscle relaxation ( J:40165 )

• reduction in the rate of ventricular relaxation

decreased systemic arterial blood pressure ( J:40165 )

homeostasis/metabolism

abnormal cardiac thrombosis ( J:40165 )

• thrombi evident in left ventricular wall and occluding the highly dilated right atrium

muscle

heart left ventricle hypertrophy ( J:40165 )

• hypertrophy of left ventricular septum and free wall

• thickening of endothelium of the left ventricle with fibrous tissue

• myocyte hypertrophy

decreased cardiac muscle contractility ( J:40165 , J:107848 )

• hypodynamic; maximal rates of contraction and relaxation are reduced to 40% of the values obtained for controls (J:40165)

• skinned fiber bundles from transgenic mouse hearts ectopically expressing enteric smooth muscle gamma-actin show no differences in maximum Ca²⁺ activated tension or maximum rate of tension redevelopment after a quick release and rapid restretch protocol (J:107848)

• however, transgenic fiber bundles exhibit a reduced sensitivity to Ca²⁺ tension and an increased economy of force development (~35% less ATP hydrolysis) relative to nontransgenic fiber bundles (J:107848)

• reduced sensitivity to Ca²⁺ tension coupled with slower cross-bridge cycling rates are likely to account for the slow rate of contraction noted in the intact heart (J:107848)

decreased heart ventricle muscle contractility ( J:40165 )

• significantly reduced rate of ventricular contraction and relaxation

abnormal cardiac muscle relaxation ( J:40165 )

• reduction in the rate of ventricular relaxation

growth/size/body

enlarged heart ( J:40165 )

• enlarged, rounded hearts

heart left ventricle hypertrophy ( J:40165 )

• hypertrophy of left ventricular septum and free wall

• thickening of endothelium of the left ventricle with fibrous tissue

• myocyte hypertrophy