About   Help   FAQ
Phenotypes Associated with This Genotype
Genotype
MGI:5810083
Allelic
Composition
Skiltm2Spw/Skiltm2Spw
Genetic
Background
involves: 129S1/Sv * 129X1/SvJ
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Skiltm2Spw mutation (1 available); any Skil mutation (38 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
endocrine/exocrine glands
• females show impaired mammary gland structural differentiation, secretory activation, tight junction formation and milk production at the onset of lactation
• females show impaired mammary gland structural and functional differentiation at day 18.5 of pregnancy
• mammary glands show a markedly reduced epithelial content at both day 18.5 of pregnancy and day 0.5 of lactation
• primary mammary epithelial cells (MECs) fail to differentiate properly in 3D culture and show early growth arrest, unlike wild-type MECs; acini are much smaller and show abnormal morphology and disrupted basal polarity while the number of cells per acinus is significantly lower than that in wild-type acini at days 3 and 5 of 3D culture
• large cytoplasmic lipid droplets are present in the luminal epithelial layer at day 0.5 and day 1 of lactation, suggesting that secretory activation fails to occur
• mammary glands exhibit significantly fewer alveoli at both day 18.5 of pregnancy and day 0.5 of lactation
• alveoli are small and poorly differentiated, with small lumens containing very few milk droplets at day 18.5 of pregnancy
• all secretory alveolar cells show loss or mislocalization of tight junctions at day 0.5 and day 1 of lactation, as shown by ZO-1 (zonula occludens 1) staining, unlike wild-type cells which show intense ZO-1 apical staining
• however, no differences are detected in cadherin junction structure, as shown by the normal level and basal localization of E-cadherin
• at day 18.5 of pregnancy, alveolar cells exhibit a much lower rate of proliferation than that observed in wild-type cells, as shown by Pcna staining
• however, no differences in apoptosis are detected at day 18.5 of pregnancy by TUNEL staining
• alveoli exhibit small lumens containing very few milk droplets at day 18.5 of pregnancy
• expression of beta-casein is reduced at late pregnancy
• whey acidic protein (Wap) mRNA levels are reduced by at least a 90% at early lactation
• no pups derived from mutant females survive beyond 3 days after birth following the first pregnancy, and newborn pups contain very little gastric milk
• however, mutant females are able to overcome the lactation defects during their second pregnancies and nurse their pups

reproductive system
• females show impaired mammary gland structural and functional differentiation at day 18.5 of pregnancy

integument
• females show impaired mammary gland structural differentiation, secretory activation, tight junction formation and milk production at the onset of lactation
• females show impaired mammary gland structural and functional differentiation at day 18.5 of pregnancy
• mammary glands show a markedly reduced epithelial content at both day 18.5 of pregnancy and day 0.5 of lactation
• primary mammary epithelial cells (MECs) fail to differentiate properly in 3D culture and show early growth arrest, unlike wild-type MECs; acini are much smaller and show abnormal morphology and disrupted basal polarity while the number of cells per acinus is significantly lower than that in wild-type acini at days 3 and 5 of 3D culture
• large cytoplasmic lipid droplets are present in the luminal epithelial layer at day 0.5 and day 1 of lactation, suggesting that secretory activation fails to occur
• mammary glands exhibit significantly fewer alveoli at both day 18.5 of pregnancy and day 0.5 of lactation
• alveoli are small and poorly differentiated, with small lumens containing very few milk droplets at day 18.5 of pregnancy
• all secretory alveolar cells show loss or mislocalization of tight junctions at day 0.5 and day 1 of lactation, as shown by ZO-1 (zonula occludens 1) staining, unlike wild-type cells which show intense ZO-1 apical staining
• however, no differences are detected in cadherin junction structure, as shown by the normal level and basal localization of E-cadherin
• at day 18.5 of pregnancy, alveolar cells exhibit a much lower rate of proliferation than that observed in wild-type cells, as shown by Pcna staining
• however, no differences in apoptosis are detected at day 18.5 of pregnancy by TUNEL staining
• alveoli exhibit small lumens containing very few milk droplets at day 18.5 of pregnancy
• expression of beta-casein is reduced at late pregnancy
• whey acidic protein (Wap) mRNA levels are reduced by at least a 90% at early lactation
• no pups derived from mutant females survive beyond 3 days after birth following the first pregnancy, and newborn pups contain very little gastric milk
• however, mutant females are able to overcome the lactation defects during their second pregnancies and nurse their pups


Contributing Projects:
Mouse Genome Database (MGD), Gene Expression Database (GXD), Mouse Models of Human Cancer database (MMHCdb) (formerly Mouse Tumor Biology (MTB)), Gene Ontology (GO)
Citing These Resources
Funding Information
Warranty Disclaimer, Privacy Notice, Licensing, & Copyright
Send questions and comments to User Support.
last database update
05/07/2024
MGI 6.23
The Jackson Laboratory