Phenotypes associated with this allele

• Allele Symbol: Kcnh7^em2Hhtg
• Allele Name: endonuclease-mediated mutation 2, Irm Hermans-Borgmeyer
• Allele ID: MGI:7778467
• Summary: 1 genotype

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Kcnh7^em2Hhtg/Kcnh7^em2Hhtg	C57BL/6J-Kcnh7^em2Hhtg	MGI:8435039

Genotype
MGI:8435039

hm1

• Allelic Composition: Kcnh7^em2Hhtg/Kcnh7^em2Hhtg
• Genetic Background: C57BL/6J-Kcnh7^em2Hhtg

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

behavior/neurological

increased depression-related behavior ( J:358013 )

• in the marble burying test, mice show less digging across the test period and bury fewer marbles over time indicating depressive-like behavior

impaired coordination ( J:358013 )

• mice exhibit reduced performance on the accelerating rod: with increasing speed and shorter time intervals between trials, mice remain on the accelerating rod for shorter times

• however, mice perform similarly to wild-type mice at low constant speed during the first two trials

decreased vertical activity ( J:358013 )

• number of rearing events is decreased

decreased locomotor activity ( J:358013 )

• mice move similar distances as wild-type mice during the first half of the test period in the open field test, but move shorter distances during the second half of the observation time

• the mean velocity of mice in the open field test is decreased over time, however the mean distance to the walls remains the same as in wild-type mice

• mice move significantly less during day 3 of the novel recognition test

• however, mice exhibit similar behavior to wild-type mice in the elevated plus maze, in social recognition, and in the novel object recognition test

nervous system

nervous system phenotype ( J:358013 )

N • mice show no gross anatomical abnormalities of the brain regarding foliation or organization of cellular layers in the cortex, hippocampus, and cerebellum

abnormal nervous system electrophysiology ( J:358013 )

• Purkinje cells, but not CA1 neurons, are hyperexcitable

• resting potential of Purkinje cells (PCs) from adolescent mice is initially depolarized (-57.8+/-0.4 mV) and different from the resting potential of wild-type Purkinje cells (-59.4+/-0.6 mV) and the resting potential remains unaltered after application of the sulfonanilide E-4031 which blocks erg K⁺ channels

• PCs from adult mice exhibit an increased resting frequency of action potential firing, with values significantly higher than the resting activity of wild-type mice and upon application of E-4031, a further increase in frequency of action potential firing is seen which is not observed in adolescent mice

• while wild-type PCs elicited with low stimuli show increased repetitive activity in response to E-4031, mutant PCs already have higher control repetitive activity which does not increase further after application of E-4031

• the increase in spontaneous and repetitive activity is accompanied by a decrease in the threshold potential and a higher membrane resistance

• however, the resting potential of CA1 neurons is not different from wild-type and remains unchanged in the presence of E-403, CA1 neurons do not show any increase in the resting spontaneous activity and E-4031 application has no effect on the low spontaneous activity of CA1 neurons, repetitive activity is not altered by synaptic blockers in CA1 neurons similarly to wild-type neurons and the M current is unchanged

abnormal action potential ( J:358013 )

• mice exhibit hyperexcitability with increased action potential firing in Purkinje cells but not CA1 neurons