Phenotypes associated with this allele

• Allele Symbol: Dnajb4^em1Sngi
• Allele Name: endonuclease-mediated mutation 1, Satoru Noguchi
• Allele ID: MGI:7444110
• Summary: 2 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Dnajb4^em1Sngi/Dnajb4^em1Sngi	involves: C57BL/6J	MGI:7444382
ht2	Dnajb4^em1Sngi/Dnajb4^+	involves: C57BL/6J	MGI:7444383

Genotype
MGI:7444382

hm1

• Allelic Composition: Dnajb4^em1Sngi/Dnajb4^em1Sngi
• Genetic Background: involves: C57BL/6J

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

muscle

abnormal sarcomere morphology ( J:333950 )

• soleus muscle shows degenerated sarcomeres with sequestered filaments, with relatively spared Z-discs seen in the vicinity of lesions

abnormal skeletal muscle morphology ( J:333950 )

• muscles accumulate aggregated and insoluble myofibrillar proteins at 28 months of age

• Z-disc components and HSP70 accumulate in muscle at 13 months of age

abnormal skeletal muscle fiber morphology ( J:333950 )

• soleus muscle myofibrils from 13-month-old mice show a wide range of characteristic lesions showing disrupted myofibrils and electron-dense material along the longitudinal axis in myofibers, some spanning 40 sarcomeres

• low-density lesions contain amorphous material

• electron dense structures composed of wooly and sand-like pleomorphic structures are seen

• diaphragm shows variation in fiber size, cytoplasmic inclusions, and widespread lesions with disorganized myofibrils and wooly sand-like material

• muscles accumulate aggregated and insoluble myofibrillar proteins at 28 months of age

• Z-disc components and HSP70 accumulate in muscle at 13 months of age

abnormal diaphragm morphology ( J:333950 )

• 13-month-old diaphragm shows variation in fiber size and cytoplasmic inclusions; fibers with cytoplasmic inclusions are predominantly type I fibers

• diaphragm shows widespread lesions showing disorganized myofibrils and wooly sand-like material

Genotype
MGI:7444383

ht2

• Allelic Composition: Dnajb4^em1Sngi/Dnajb4⁺
• Genetic Background: involves: C57BL/6J

muscle

abnormal skeletal muscle morphology ( J:333950 )

• muscles accumulate aggregated and insoluble myofibrillar proteins at 28 months of age

• Z-disc components and HSP70 accumulate in muscle at 28 months of age

abnormal skeletal muscle fiber morphology ( J:333950 )

• 28-month-old soleus shows variation in fiber size, increase in fibers with internal nuclei, and cytoplasmic inclusions

• soleus of 28-month-old mice shows an increase in fibers with p62+ inclusions

decreased skeletal muscle fiber size ( J:333950 )

• soleus muscle fiber size is decreased at 11 months of age

increased variability of skeletal muscle fiber size ( J:333950 )

• soleus muscle shows greater variation in fiber size at 28 months of age

skeletal muscle atrophy ( J:333950 )

• mice develop myofiber atrophy

skeletal muscle fibrosis ( J:333950 )

• muscle fibrosis is seen in soleus of 28-month-old mice

impaired skeletal muscle contractility ( J:333950 )

• absolute isometric force and cross-sectional area-normalized isometric force of the soleus muscle are lower in 11- and 28-month old mice

• twitch-tetanic ratio and valley-to-peak slope of isometric force are lower in soleus suggesting muscles slowly contract on electric stimuli

muscle weakness ( J:333950 )

• mice develop muscle weakness

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
distal myopathy		DOID:11720	OMIM:PS160500	J:333950