Phenotypes associated with this allele

• Allele Symbol: Ryr1^em1Zor
• Allele Name: endonuclease-mediated mutation 1, Francesco Zorzato
• Allele ID: MGI:7339039
• Summary: 2 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
ht1	Ryr1^em1Zor/Ryr1^+	C57BL/6J-Ryr1^em1Zor	MGI:7626249
ht2	Ryr1^em1Zor/Ryr1^em2Zor	C57BL/6J-Ryr1^em1Zor Ryr1^em2Zor	MGI:7626241

Genotype
MGI:7626249

ht1

• Allelic Composition: Ryr1^em1Zor/Ryr1⁺
• Genetic Background: C57BL/6J-Ryr1^em1Zor

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

muscle

muscle phenotype ( J:275501 , J:291685 )

N • normal fast to slow fiber ratio in extensor digitorum longus (EDL) and soleus muscles (J:275501)

N • normal wet weight of extensor digitorum longus (EDL) and soleus muscles (J:275501)

N • normal single electrical-pulse-induced mean force in extraocular muscle (J:291685)

N • normal extraocular muscle length, weight and cross section (J:291685)

abnormal skeletal muscle fiber triad morphology ( J:275501 )

• fewer calcium release units (CRUs) in extensor digitorum longus (EDL) fibers; greater percentage of dyads and CRUs absent from some EDL muscle fiber cores

skeletal muscle fiber degeneration ( J:275501 )

• atrophy of fast fibers in extensor digitorum longus (EDL) muscle as indicated by reduction of minimal Ferets fiber diameter

• normal in soleus muscle

muscle weakness ( J:275501 )

• 20% and 30% decrease of specific twitch peak force in extensor digitorum longus (EDL) and soleus muscles, respectively, after application of single action potential

• 23% reduction in maximal specific tetanic force in extensor digitorum longus (EDL) and soleus muscles after application of 50/100/120/150 Hz train of action potentials

vision/eye

vision/eye phenotype ( J:291685 )

N • normal visual acuity

behavior/neurological

decreased locomotor activity ( J:275501 )

• 25% decrease in voluntary activity (running distance) and lower median cruise speed on running wheel

homeostasis/metabolism

abnormal calcium ion homeostasis ( J:275501 )

• 15% reduction in peak Ca2+ transients induced by single action potential in extensor digitorum longus (EDL) muscle fibers

• 20% reduction in peak Ca2+ transients induced by 100 Hz action potential train in extensor digitorum longus (EDL) and soleus muscle fibers

• normal resting Ca2+ concentrations in extensor digitorum longus (EDL) and soleus muscle fibers

• normal peak Ca2+ transients induced by single action potential in soleus muscle fibers

growth/size/body

growth/size/body region phenotype ( J:275501 , J:292405 )

N • normal body weight and growth after birth (J:275501)

N • normal body weight and growth after birth (J:292405)

embryo

embryo phenotype ( J:275501 , J:292405 )

N • normal embryonic development (J:275501)

N • normal embryonic development (J:292405)

Genotype
MGI:7626241

ht2

• Allelic Composition: Ryr1^em1Zor/Ryr1^em2Zor
• Genetic Background: C57BL/6J-Ryr1^em1Zor Ryr1^em2Zor

muscle

abnormal extraocular muscle morphology ( J:291685 )

• less than 90% reduced single electrical-pulse-induced mean force

• longer half relaxation after activation by single action potential

• normal length, weight and cross section

abnormal muscle fiber morphology ( J:291685 )

• fewer calcium release units (CRUs) and mitochondria in extraocular muscle; greater percentage of dyads

• misalignment of Z-discs in 80% of extraocular muscle fibers

• swelling of terminal cisternae in EOM fibers

abnormal skeletal muscle fiber morphology ( J:292405 )

• cores of disorganized morphology in extensor digitorum longus (EDL) muscles

• mitochondria and calcium release units (CRUs) absent from some EDL muscle fiber cores

abnormal skeletal muscle fiber mitochondrial morphology ( J:292405 )

• fewer mitochondria in extensor digitorum longus (EDL) fibers; mitochondria absent from some fiber cores

• normal number of mitochondria in flexor digitorum brevis (FDB) and soleus fibers

abnormal skeletal muscle fiber triad morphology ( J:292405 )

• fewer calcium release units (CRUs) in extensor digitorum longus (EDL) fibers; greater percentage of dyads and CRUs absent from some EDL muscle fiber cores

skeletal muscle fiber degeneration ( J:292405 )

• atrophy of fast fibers in extensor digitorum longus (EDL) muscle as indicated by reduction of minimal Ferets fiber diameter

• normal in soleus muscle

decreased skeletal muscle weight ( J:292405 )

• 10% reduction in extensor digitorum longus (EDL) and soleus muscle weight

muscle weakness ( J:292405 )

• 60% and 50% decrease of specific twitch peak force in extensor digitorum longus (EDL) and soleus muscles, respectively, after application of single action potential

• shorter time to peak and half relaxation time in extensor digitorum longus (EDL) and soleus muscles after application of single action potential

• 30% reduction in maximal specific tetanic force in extensor digitorum longus (EDL) and soleus muscles after application of 150 Hz train of action potentials

cellular

abnormal skeletal muscle fiber mitochondrial morphology ( J:292405 )

• fewer mitochondria in extensor digitorum longus (EDL) fibers; mitochondria absent from some fiber cores

• normal number of mitochondria in flexor digitorum brevis (FDB) and soleus fibers

behavior/neurological

decreased locomotor activity ( J:292405 )

• 40% decrease in voluntary activity (running distance) and lower median cruise speed on running wheel

growth/size/body

slow postnatal weight gain ( J:292405 )

• 20% lower weight after weaning

• normal between birth and weaning

homeostasis/metabolism

abnormal calcium ion homeostasis ( J:291685 , J:292405 )

• 50% reduction in peak Ca2+ transients induced by single action potential in extraocular muscle (J:291685)

• longer half relaxation time after activation by single action potential in extraocular muscle (J:291685)

• normal half time to peak and time to peak Ca2+ transients induced by single action potential in extraocular muscle (J:291685)

• 40-50% reduction in peak Ca2+ transients induced by single action potential in extensor digitorum longus (EDL), flexor digitorum brevis (FDB) and soleus muscle fibers (J:292405)

• 40-50% reduction in peak Ca2+ transients induced by 100 Hz action potential train in extensor digitorum longus (EDL) and flexor digitorum brevis (FDB) muscle fibers (J:292405)

• 13% reduction in peak Ca2+ transients induced by 100 Hz action potential train in soleus muscle fibers (J:292405)

• 15% faster rising phase of peak Ca2+ transients induced by single action potential in EDL muscle fibers (J:292405)

• longer half relaxation time in FDB and soleus muscle fibers activated by single action potential (J:292405)

• shorter half relaxation time in EDL muscle fibers activated by single action potential (J:292405)

• normal resting Ca2+ concentrations in extensor digitorum longus (EDL), flexor digitorum brevis (FDB) and soleus muscle fibers (J:292405)

• normal rising phase of peak Ca2+ transients induced by single action potential in FDB and soleus muscle fibers (J:292405)

embryo

embryo phenotype ( J:292405 )

N • normal embryonic development

vision/eye

vision/eye phenotype ( J:291685 )

N • normal visual acuity

abnormal extraocular muscle morphology ( J:291685 )

• less than 90% reduced single electrical-pulse-induced mean force

• longer half relaxation after activation by single action potential

• normal length, weight and cross section

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
congenital myopathy 1B		DOID:0080991	OMIM:255320	J:291685 , J:292405