Project description:Akt1, a serine-threonine protein kinase member of the PKB/Akt gene family, plays a critical role in the regulation of several cellular processes including cell proliferation and apoptosis. In this study, we utilized Akt1+/+ and Akt1¬-/- C57/Bl6 female mice to demonstrate that Akt1 is required for normal mammary gland postnatal development and homeostasis. Akt1 deficiency resulted in severely delayed postnatal mammary gland growth as well as a significant decrease in the number of terminal end buds during puberty. Adult Akt1-/- mammary glands exhibited significantly fewer alveolar buds coupled with a significant increase in epithelial cell apoptosis compared to their wild-type counterparts. Microarray analysis revealed that Akt1 deficiency resulted in several altered gene expression changes and biological processes in adult mammary glands, including organismal development, cell death, and tissue morphology. Of particular importance, a significant decrease in expression of Btn1a1, a gene involved in milk lipid secretion, was observed in Akt1-/- mammary glands by both microarray and RT-PCR validation. Transcriptome analysis of Akt1 wild type and akt1-homozygous mouse mammary glands wild type mammary glands from 3 mice and Akt1-deficient mammary glands from 3 mice were analyzed for differences in gene expression at postnatal day 70
Project description:Akt1, a serine-threonine protein kinase member of the PKB/Akt gene family, plays a critical role in the regulation of several cellular processes including cell proliferation and apoptosis. In this study, we utilized Akt1+/+ and Akt1¬-/- C57/Bl6 female mice to demonstrate that Akt1 is required for normal mammary gland postnatal development and homeostasis. Akt1 deficiency resulted in severely delayed postnatal mammary gland growth as well as a significant decrease in the number of terminal end buds during puberty. Adult Akt1-/- mammary glands exhibited significantly fewer alveolar buds coupled with a significant increase in epithelial cell apoptosis compared to their wild-type counterparts. Microarray analysis revealed that Akt1 deficiency resulted in several altered gene expression changes and biological processes in adult mammary glands, including organismal development, cell death, and tissue morphology. Of particular importance, a significant decrease in expression of Btn1a1, a gene involved in milk lipid secretion, was observed in Akt1-/- mammary glands by both microarray and RT-PCR validation. Transcriptome analysis of Akt1 wild type and akt1-homozygous mouse mammary glands
Project description:This study determines pineal gland gene expression levels in the NeuroD1 knockout mouse at postnatal day zero. Comparison was performed against pineal gland gene expression levels in 129 wildtype mice also disected at P0. Keywords: Comparison of wildtype versus transgenic pineal gland gene expression
Project description:To investigate the dynamic changes in gene expression during mammary gland development and lactation in sows, mammary tissue samples were collected from 30 multiparous crossbred half-sibling sows (Danish Landrace × Yorkshire) housed under standardized conditions. Samples were obtained at five critical physiological stages: mid-gestation (Day 70), late gestation (Day 110), early lactation (Day 2 postpartum), peak lactation (Day 10 postpartum), and early involution (Day 2 post-weaning), with six biological replicates per stage. Parenchymal mammary tissue (0.5–1 cm³) was excised from a defined location below the third pair of teats and rapidly snap-frozen in liquid nitrogen for RNA preservation. All instruments were treated with RNase inhibitors to ensure RNA integrity. The collected samples were stored at –80°C for subsequent total RNA extraction and transcriptome sequencing, providing a valuable resource for elucidating molecular mechanisms underlying mammary gland remodeling and lactation regulation in sows.
Project description:AKT1 is a serine/threonine kinase implicated in fetal, placental, and postnatal growth. In this study, we investigated roles for AKT1 in placental development using a genome-edited/loss-of-function rat model. Both heterozygous and homozygous Akt1 mutant rats were viable and fertile. Disruption of AKT1 resulted in placental, fetal, and postnatal growth restriction. Akt1 null placentas showed deficits in both junctional zone and labyrinth zone size and their ability to adapt to a physiological stressor. Robust differences in the transcriptome of wild type versus Akt1 null junctional zones were identified. Among the differentially expressed junctional zone transcripts was forkhead box O4 (Foxo4), which encodes a transcription factor and known AKT substrate. FOXO4 expression was prominent in the junctional zone and invasive trophoblast cells of the rat placentation site and enhanced following rat TS cell differentiation. Foxo4 gene disruption using genome-editing resulted in placentomegaly, including an enlarged junctional zone. AKT1 and FOXO4 regulate the expression of many of the same transcripts expressed by trophoblast cells; however, in opposite directions. In summary, we have identified AKT1 and FOXO4 as part of a regulatory network controlling hemochorial placenta development.
Project description:AKT1 is a serine/threonine kinase implicated in fetal, placental, and postnatal growth. In this study, we investigated roles for AKT1 in placental development using a genome-edited/loss-of-function rat model. Both heterozygous and homozygous Akt1 mutant rats were viable and fertile. Disruption of AKT1 resulted in placental, fetal, and postnatal growth restriction. Akt1 null placentas showed deficits in both junctional zone and labyrinth zone size and their ability to adapt to a physiological stressor. Robust differences in the transcriptome of wild type versus Akt1 null junctional zones were identified. Among the differentially expressed junctional zone transcripts was forkhead box O4 (Foxo4), which encodes a transcription factor and known AKT substrate. FOXO4 expression was prominent in the junctional zone and invasive trophoblast cells of the rat placentation site and enhanced following rat TS cell differentiation. Foxo4 gene disruption using genome-editing resulted in placentomegaly, including an enlarged junctional zone. AKT1 and FOXO4 regulate the expression of many of the same transcripts expressed by trophoblast cells; however, in opposite directions. In summary, we have identified AKT1 and FOXO4 as part of a regulatory network controlling hemochorial placenta development.
Project description:Mammary gland branching morphogenesis is thought to relie on the mobilization of the membrane-anchored matrix metalloproteinase, Mmp14/MT1-MMP, to drive mammary epithelial invasion by remodeling the extracellular matrix and triggering associated signaling cascades. However, the roles that this proteinase plays during postnatal mammary gland development in vivo remain undefined. A mammary gland branching program that occurs during the first 4 weeks of postnatal mouse development, in tandem with recently developed Mmp14-floxed mice and MMTV-Cre transgenics that express Cre recombinase throughout the mammary epithelial cell compartment, were used to characterize the impact of deleting epithelial cell Mmp14 on mammary gland morphogenesis. Transcriptome profiling of mammary epithelial cells was used to investigate the effects of MMTV-Cre expression on the postnatal mammary epithelial cell compartment in an unbiased fashion
Project description:Mammary gland branching morphogenesis is thought to relie on the mobilization of the membrane-anchored matrix metalloproteinase, Mmp14/MT1-MMP, to drive mammary epithelial invasion by remodeling the extracellular matrix and triggering associated signaling cascades. However, the roles that this proteinase plays during postnatal mammary gland development in vivo remain undefined. A mammary gland branching program that occurs during the first 4 weeks of postnatal mouse development, in tandem with recently developed Mmp14-floxed mice and MMTV-Cre transgenics that express Cre recombinase throughout the mammary epithelial cell compartment, were used to characterize the impact of deleting epithelial cell Mmp14 on mammary gland morphogenesis. Transcriptome profiling of mammary epithelial cells was used to investigate the functional roles of MT1-MMP in the postnatal mammary epithelial cell compartment in an unbiased fashion