Phenotypes Associated with This Genotype

Genotype
MGI:5752579

• Allelic Composition: Gars1^Nmf249/Gars1⁺; Tg(Thy1-YFP)16Jrs/?
• Genetic Background: involves: C57BL/6J * CAST/Ei * CBA/J

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

nervous system

abnormal neuromuscular synapse morphology ( J:229590 )

• nearly all terminals assessed in the levator auris longus show more diffuse postsynaptic staining, less distinct gutters, thinner axons and presynaptic nerves, synapses that are smaller than in wild-type controls, fewer mitochondria at the synaptic terminals, and the average quantal content is significantly lower than normal

• at high magnification, but not evident at low magnification, approximately half of the junctions assesed in the levator auris longus at 2 months of age are found to be only partially innervated, even in the mildly affected mice, and there are more than 3 times as many denervated junctions at 2 months of age as are found in carriers of the C201R allele at 4 months of age

abnormal synaptic transmission ( J:229590 )

abnormal PNS synaptic transmission ( J:229590 )

• at 2 months of age 25% decrease in amplitude of evoked endplate currents, and quantal content in neuromuscular synapses the levator auris longus muscle

• at 2 months of age the frequency of spontaneous release is consistently lower than normal although the quantal amplitude at synapses is normal, and no differences are found in the miniature endplate current amplitude

abnormal endplate potential ( J:229590 )

behavior/neurological

decreased grip strength ( J:229590 )

• compared with wild-type controls, heterozygotes have impaired grip strength and this is improved by treatment with physostigmine