mortality/aging
• seen in the second year of life
|
cellular
• in double heterozygous MEFs after 5 passages aneuploid cells are increased by 32% compared to wild-type cells and a wider range of nonmodal chromosome numbers is seen compared to single heterozygous or wild-type MEFs
(J:81546)
• at 5 months of age, 37% of splenocytes are aneuploid compared to 9% in single heterozygotes
(J:81546)
• the number of aneuploid splenocytes increases from 37% at 5 months to 47% at 24 months compared to only 3% in wild-type mice at 35 months
(J:105717)
|
• after nocodazole treatment the time for 50% of cells to exit prometaphase arrest is reduced to 2.2 hours compared to 7.2 hours for wild-type MEFs
|
• prematurely separated sister chromatids are seen in 19% and 13% of mitotic figures from MEFs and splenocytes (at 5 months of age), respectively
(J:81546)
• lagging chromosomes are seen in 15% of anaphase figures compared to 5% of single heterozygous and 2% of wild-type figures
(J:81546)
• in splenocytes prematurely separated sister chromatids increase from 14% at 5 months to being present in 24% of metaphases at 24 months compared to 0 at 27 months and only 4% at 35 months in wild-type
(J:105717)
• however, no chromosome breaks or fusions are seen at 24 months of age
(J:105717)
• 47% of anaphases have multiple lagging chromosomes compared to 0% in wild-type MEFs
(J:105717)
|
• double heterozygous MEFs grow slower than single heterozygous or wild-type MEFs
|
• at passage 5 and 7 increased expression of senescence related genes in MEFs is seen
• at passage 7 but not passage 3, double heterozygous MEFs grow slower than single heterozygous or wild-type MEFs
|
adipose tissue
• decreased thickness of the subcutaneous adipose tissue
|
• at 27 months of age a dramatic decrease in body fat is seen
|
growth/size/body
weight loss
(
J:105717
)
• body weight is similar to wild-type at 5 months of age but significantly lower by 24 months of age
|
muscle
• clear signs of skeletal muscle degeneration and atrophy are seen in mice with lordokyphosis
|
• clear signs of skeletal muscle degeneration and atrophy are seen in mice with lordokyphosis
|
skeleton
• lordokyphosis is seen at an earlier age and with increased severity compared to single heterozygous or wild-type mice
|
vision/eye
• incidence of cataract formation is increased and the latency is decreased compared to single heterozygotes
|
neoplasm
• a single application of 50 ul of 0.5% DMBA at P5 results in an increased incidence of lung tumors and more tumors per animal in double heterozygotes compared to wild-type mice
• however, no difference in spontaneous tumor incidence is seen compared to wild-type mice
|
homeostasis/metabolism
• a single application of 50 ul of 0.5% DMBA at P5 results in an increased incidence of lung tumors and more tumors per animal in double heterozygotes compared to wild-type mice
• however, no difference in spontaneous tumor incidence is seen compared to wild-type mice
|
integument
• decreased thickness of the subcutaneous adipose tissue
|
• from 5 to 27 months of age dermal thickness decreases by 21% lower compared a decrease of 9% in wild-type mice
|