Phenotypes associated with this allele

• Allele Symbol: Tg(Myh7-Pln)2Egk
• Allele Name: transgene insertion 2, Evangelia G Kranias
• Allele ID: MGI:3834218
• Summary: 2 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
tg1	Tg(Myh7-Pln)2Egk/0	FVB/N-Tg(Myh7-Pln)2Egk	MGI:5052046
tg2	Tg(Myh7-Pln)2Egk/?	involves: FVB/N	MGI:6108871

Genotype
MGI:5052046

tg1

• Allelic Composition: Tg(Myh7-Pln)2Egk/0
• Genetic Background: FVB/N-Tg(Myh7-Pln)2Egk

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

behavior/neurological

impaired exercise endurance ( J:224766 )

• mice reach exhaustion much sooner than wild-type mice during a treadmill exercise test

muscle

decreased soleus weight ( J:224766 )

• soleus:body-weight ratio at 1 month, 4-6 months and 10-12 months of age shows a 21%, 43%, and 41% reduction, respectively

abnormal skeletal muscle fiber morphology ( J:224766 )

• soleus muscle exhibits type I fiber hypotrophy as early as 1 month of age and type II fiber hypertrophy

• muscle fibers show radiating sarcoplasmic reticulum strands

centrally nucleated skeletal muscle fibers ( J:224766 )

• central nucleation of muscle fibers with low regeneration, progressive fibrosis and a small elevation in plasma creatine kinase indicate centronuclear myopathy

• both soleus and gluteus minimus muscle show signs of centronuclear myopathy

abnormal skeletal muscle fiber type ratio ( J:224766 )

• type I fiber predominance is established at 4-6 months of age

skeletal muscle atrophy ( J:94077 , J:224766 )

• soleus muscle atrophy (J:224766)

skeletal muscle fibrosis ( J:224766 )

• soleus muscles show progressive fibrosis

skeletal muscle endomysial fibrosis ( J:224766 )

• endomysial fibrosis in postural gluteus minimus muscle

abnormal muscle physiology ( J:224766 )

• maximal rates of sarco(endo)plasmic reticulum calcium-ATPase activity and rates of calcium uptake are reduced in soleus muscle

• gluteus minimus muscle shows a 20% reduction in the rates of calcium uptake

impaired skeletal muscle contractility ( J:94077 )

• soleus muscle exhibits slow rates of contraction and relaxation

muscle weakness ( J:224766 )

• mice generate lower normalized force at both submaximal and maximal stimulation frequencies (30-100 Hz)

• twitch kinetics are slower in soleus muscle

• however, normalized twitch force generation is not different

myopathy ( J:224766 )

• soleus muscles show greater central nucleation of fibers, fiber splitting, atrophy and progressive fibrosis, which becomes evident at 4-6 months of age indicating myopathy

cellular

oxidative stress ( J:224766 )

• mice show greater whole muscle oxidative stress

• soleus muscle exhibits central aggregation of oxidative activity

homeostasis/metabolism

impaired exercise endurance ( J:224766 )

• mice reach exhaustion much sooner than wild-type mice during a treadmill exercise test

increased creatine kinase activity ( J:224766 )

• small elevation of plasma creatine kinase levels in 4-6 month old mice

limbs/digits/tail

decreased soleus weight ( J:224766 )

• soleus:body-weight ratio at 1 month, 4-6 months and 10-12 months of age shows a 21%, 43%, and 41% reduction, respectively

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
centronuclear myopathy		DOID:14717		J:224766

Genotype
MGI:6108871

tg2

• Allelic Composition: Tg(Myh7-Pln)2Egk/?
• Genetic Background: involves: FVB/N

muscle

abnormal soleus morphology ( J:127873 )

• soleus exhibits smaller muscle size, mass, and cross-sectional area

abnormal skeletal muscle fiber type ratio ( J:127873 )

• percentage of slow type I fibers is 25% higher in soleus muscle than in wild-type mice

impaired skeletal muscle contractility ( J:127873 )

• maximal twitch rate of contraction (+dF/dt) is reduced by 40% and the maximal twitch rate of relaxation (-dF/dt) is decreased by 45%, which are associated with a 2-fold prolongation of the contraction time and half-relaxation time

• beta-adrenergic stimulation of soleus with isoproterenol partially reverses the depressed contraction time and completely reverses the half-relaxation time

• soleus shows altered isometric twitch contractions, with the force developed by soleus reduced

• however, after normalization to the cross-sectional area of the muscle, the developed force is similar to controls

impaired muscle relaxation ( J:127873 )

• maximal twitch rate of contraction (+dF/dt) is reduced by 40% and the maximal twitch rate of relaxation (-dF/dt) is decreased by 45%, which are associated with a 2-fold prolongation of the contraction time and half-relaxation time

• beta-adrenergic stimulation of soleus with isoproterenol partially reverses the depressed contraction time and completely reverses the half-relaxation time

limbs/digits/tail

abnormal soleus morphology ( J:127873 )

• soleus exhibits smaller muscle size, mass, and cross-sectional area