Phenotypes associated with this allele

• Allele Symbol: Mchr1^tm1Sqn
• Allele Name: targeted mutation 1, Su Qian
• Allele ID: MGI:2451034
• Summary: 1 genotype

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Mchr1^tm1Sqn/Mchr1^tm1Sqn	involves: 129S7/SvEvBrd * C57BL/6	MGI:4456167

Genotype
MGI:4456167

hm1

• Allelic Composition: Mchr1^tm1Sqn/Mchr1^tm1Sqn
• Genetic Background: involves: 129S7/SvEvBrd * C57BL/6

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

growth/size/body

increased lean body mass ( J:81787 )

• male and female mice show about 7% greater lean mass than wild-type controls at 5-7 months

decreased susceptibility to diet-induced obesity ( J:81787 )

• females maintained on a high-fat diet for 7 weeks gain significantly more weight than wild-type females maintained on regular chow, but weight gain is the same as mutant females fed regular chow for the same period

• resistance to diet-induced obesity is due to hyperactivity and increased energy expenditure

homeostasis/metabolism

homeostasis/metabolism phenotype ( J:81787 )

N • plasma glucose, insulin, and triglyceride level are not different from controls in 5-7 month old males

N • mice show normal responses to orexigenics (NPY, AgRP); chronic melanin-concentrating hormone administration (6 days) has no effect on mutants, whereas wild-type mice show significant increases in food intake, weight gains, and altered body compositions

decreased susceptibility to diet-induced obesity ( J:81787 )

• females maintained on a high-fat diet for 7 weeks gain significantly more weight than wild-type females maintained on regular chow, but weight gain is the same as mutant females fed regular chow for the same period

• resistance to diet-induced obesity is due to hyperactivity and increased energy expenditure

decreased respiratory quotient ( J:81787 )

• significantly lower in male mutants during light phase, whereas RQ is comparable to wild-type mice during light phase

abnormal hormone level ( J:81787 )

• corticotrophin-releasing factor (CRF) mRNA levels in the paraventricular nucleus of the hypothalamus are significantly lower in males relative to wild-type, but are normal in the central nucleus of the amygdala

increased circulating corticosterone level ( J:81787 )

• 6-7 month-old males have significantly greater plasma corticosterone levels than wild-type

decreased circulating leptin level ( J:81787 )

• levels are significantly lower in males compared to wild-type at 5-7 months; similar trend is observed in females

decreased thyroxine level ( J:81787 )

• levels are significantly lower in males compared to wild-type at 5-7 months; similar trend is observed in females

abnormal metabolism ( J:81787 )

• mice have significantly greater metabolic rate during part of the dark phase, correlating with the period of hyperactivity

behavior/neurological

increased fluid intake ( J:81787 )

• hyperphagia is accompanied by increased drinking behavior (increased duration)

polyphagia ( J:81787 )

• animals exhibit hyperphagia (15.8% and 12.3% greater food intake by males and females, respectively) on regular mouse chow and when group- or individually-housed; hyperphagia in the range of 12-24% is consistently observed

• hyperphagia is result of significantly increased eating duration; behavior is restricted entirely to dark phase of light-dark cycle

increased locomotor activity ( J:81787 )

• mice are 2x more active during dark phase compared to controls, but show normal levels of ambulatory activity during light phase; mice exhibit significantly more fine motor movements during dark phase relative to wild-type

adipose tissue

decreased percent body fat/body weight ( J:81787 )

• male and female mice have about 50% less fat mass than wild-type at 5-7 months