Project description:PURPOSE: To provide a detailed gene expression profile of the normal postnatal mouse cornea. METHODS: Serial analysis of gene expression (SAGE) was performed on postnatal day (PN)9 and adult mouse (6 week) total corneas. The expression of selected genes was analyzed by in situ hybridization. RESULTS: A total of 64,272 PN9 and 62,206 adult tags were sequenced. Mouse corneal transcriptomes are composed of at least 19,544 and 18,509 unique mRNAs, respectively. One third of the unique tags were expressed at both stages, whereas a third was identified exclusively in PN9 or adult corneas. Three hundred thirty-four PN9 and 339 adult tags were enriched more than fivefold over other published nonocular libraries. Abundant transcripts were associated with metabolic functions, redox activities, and barrier integrity. Three members of the Ly-6/uPAR family whose functions are unknown in the cornea constitute more than 1% of the total mRNA. Aquaporin 5, epithelial membrane protein and glutathione-S-transferase (GST) omega-1, and GST alpha-4 mRNAs were preferentially expressed in distinct corneal epithelial layers, providing new markers for stratification. More than 200 tags were differentially expressed, of which 25 mediate transcription. CONCLUSIONS: In addition to providing a detailed profile of expressed genes in the PN9 and mature mouse cornea, the present SAGE data demonstrate dynamic changes in gene expression after eye opening and provide new probes for exploring corneal epithelial cell stratification, development, and function and for exploring the intricate relationship between programmed and environmentally induced gene expression in the cornea. Keywords: other
Project description:The functional status of the tumor repressor protein (TP53 or TRP53) is a defining feature of ovarian cancer. Mutant or null alleles of TP53 are expressed in greater than 90% of all high-grade serous adenocarcinomas. Wild type TP53 is elevated in low-grade serous adenocarcinomas in women and in our Pten/Kras/Amhr2-Cre mutant mouse model. Disruption of the Trp53 gene in this mouse model did not lead to high-grade ovarian cancer but did increase expression of estrogen receptor alpha (ERalpha; ESR1) and markedly enhanced the responsiveness of these cells to estrogen. Specifically, when Trp53 positive and Trp53 null mutant mice were treated with estradiol or vehicle, only the Trp53 null and Esr1 positive tumors respond vigorously to estradiol in vivo and exhibit features characteristic of high-grade type ovarian cancer: invasive growth into the ovarian stroma, rampant metastases to the peritoneal cavity and signs of genomic instability. Estrogen promoted and progesterone suppressed the growth of Trp53 null ovarian tumors and tumor cells injected intraperitoneally (IP), subcutaneously (SC) or when grown in matrigel. Exposure of the Trp53 depleted cells to estrogen also has a profound impact on the tumor microenvironment and immune-related events. These results led to the new paradigm that TRP53 status is related to the susceptibility of transformed ovarian surface epithelial (OSE) cells to estradiol-induced metastases and genomic instability. This novel finding is relevant not only for women during their reproductive years but also for women on hormone (estradiol) replacement therapies. A direct comparison of ovarian surface epithelia cells from two different genotype mice
Project description:We use single-cell RNA sequencing (scRNA-seq) to explore the transcriptional changes associated with estrogen-induced dysplasia in mouse ovarian surface epithelial cells
Project description:We have developed mouse models for serous epithelial ovarian cancer (SEOC) based on conditional inactivation of p53 and Rb tumor suppression (RB-TS) in combination with or without Brca1/2 following injection of adenovirus expressing Cre recombinase into the ovarian bursa. These models develop metastatic (Stage IV) disease with key histopathological features resembling human SEOC.To determine whether these mouse tumors resemble human SEOC at the molecular level, we conducted global gene expression analysis on 27 ovarian carcinomas and 3 pooled normal ovarian surface epithelium samples (single epithelial layer isolated from ovarian surface by laser capture).
Project description:We have developed mouse models for serous epithelial ovarian cancer (SEOC) based on conditional inactivation of p53 and Rb tumor suppression (RB-TS) in combination with or without Brca1/2 following injection of adenovirus expressing Cre recombinase into the ovarian bursa. These models develop metastatic (Stage IV) disease with key histopathological features resembling human SEOC.To determine whether these mouse tumors resemble human SEOC at the molecular level, we conducted global gene expression analysis on 27 ovarian carcinomas and 3 pooled normal ovarian surface epithelium samples (single epithelial layer isolated from ovarian surface by laser capture). RNA was isolated from flash frozen ovarian tumors or from ovarian surface epithelial cells microdissected from frozen sections using PixCell IIe laser capture microdissection instrument.
Project description:Introgressed variants from other species can be an important source of genetic variation because they may arise rapidly, can include multiple mutations on a single haplotype, and have often been pretested by selection in the species of origin. Although introgressed alleles are generally deleterious, several studies have reported introgression as the source of adaptive alleles-including the rodenticide-resistant variant of Vkorc1 that introgressed from Mus spretus into European populations of Mus musculus domesticus. Here, we conducted bidirectional genome scans to characterize introgressed regions into one wild population of M. spretus from Spain and three wild populations of M. m. domesticus from France, Germany, and Iran. Despite the fact that these species show considerable intrinsic postzygotic reproductive isolation, introgression was observed in all individuals, including in the M. musculus reference genome (GRCm38). Mus spretus individuals had a greater proportion of introgression compared with M. m. domesticus, and within M. m. domesticus, the proportion of introgression decreased with geographic distance from the area of sympatry. Introgression was observed on all autosomes for both species, but not on the X-chromosome in M. m. domesticus, consistent with known X-linked hybrid sterility and inviability genes that have been mapped to the M. spretus X-chromosome. Tract lengths were generally short with a few outliers of up to 2.7 Mb. Interestingly, the longest introgressed tracts were in olfactory receptor regions, and introgressed tracts were significantly enriched for olfactory receptor genes in both species, suggesting that introgression may be a source of functional novelty even between species with high barriers to gene flow.
Project description:The functional status of the tumor repressor protein (TP53 or TRP53) is a defining feature of ovarian cancer. Mutant or null alleles of TP53 are expressed in greater than 90% of all high-grade serous adenocarcinomas. Wild type TP53 is elevated in low-grade serous adenocarcinomas in women and in our Pten/Kras/Amhr2-Cre mutant mouse model. Disruption of the Trp53 gene in this mouse model did not lead to high-grade ovarian cancer but did increase expression of estrogen receptor alpha (ERalpha; ESR1) and markedly enhanced the responsiveness of these cells to estrogen. Specifically, when Trp53 positive and Trp53 null mutant mice were treated with estradiol or vehicle, only the Trp53 null and Esr1 positive tumors respond vigorously to estradiol in vivo and exhibit features characteristic of high-grade type ovarian cancer: invasive growth into the ovarian stroma, rampant metastases to the peritoneal cavity and signs of genomic instability. Estrogen promoted and progesterone suppressed the growth of Trp53 null ovarian tumors and tumor cells injected intraperitoneally (IP), subcutaneously (SC) or when grown in matrigel. Exposure of the Trp53 depleted cells to estrogen also has a profound impact on the tumor microenvironment and immune-related events. These results led to the new paradigm that TRP53 status is related to the susceptibility of transformed ovarian surface epithelial (OSE) cells to estradiol-induced metastases and genomic instability. This novel finding is relevant not only for women during their reproductive years but also for women on hormone (estradiol) replacement therapies.
Project description:In a mouse model of ovarian cancer, we have established that prolonged exposure to 17β-estradiol (E2) accelerates tumour onset and increases the incidence of morphologically dysplastic ovarian surface epithelium (OSE). OSE cell proliferation and morphology are tightly regulated by the asymmetrical distribution of polarity proteins that provide positional cues for surface localization and growth inhibition. We hypothesized that E2 causes OSE dysplasia by inhibiting a tumour suppressor gene called Disabled-2 (Dab2). Dab2 is critical in mediating the polarized distribution of cell surface proteins and is highly expressed in normal OSE, but is absent in the majority of ovarian cancers. In this study, Dab2 is shown to be suppressed by E2 and we investigated the possibility that this occurs through E2 up-regulation of microRNAs. microRNA microarray analysis comparing control vs. E2 treated mouse ovarian cancer cells (MASE) was used to identify candidate miRNAs that have a seeding sequence capable of targeting the 3-prime untranslated region (3’UTR) of both human and mouse Dab2 transcript.
Project description:Translational research is commonly performed in the C57B6/J mouse strain, chosen for its genetic homogeneity and phenotypic uniformity. Here, we evaluate the suitability of the white-footed deer mouse (Peromyscus leucopus) as a model organism for aging research, offering a comparative analysis against C57B6/J and diversity outbred (DO) Mus musculus strains. Our study includes comparisons of body composition, skeletal muscle function, and cardiovascular parameters, shedding light on potential applications and limitations of P. leucopus in aging studies. Notably, P. leucopus exhibits distinct body composition characteristics, emphasizing reduced muscle force exertion and a unique metabolism, particularly in fat mass. Cardiovascular assessments showed changes in arterial stiffness, challenging conventional assumptions and highlighting the need for a nuanced interpretation of aging-related phenotypes. Our study also highlights inherent challenges associated with maintaining and phenotyping P. leucopus cohorts. Behavioral considerations, including anxiety-induced responses during handling and phenotyping assessment, pose obstacles in acquiring meaningful data. Moreover, the unique anatomy of P. leucopus necessitates careful adaptation of protocols designed for Mus musculus. While showcasing potential benefits, further extensive analyses across broader age ranges and larger cohorts are necessary to establish the reliability of P. leucopus as a robust and translatable model for aging studies.