Space Environment Impacts Homeostasis: Exposure to Spaceflight Alters Mammary Gland Transportome Genes.

Membrane transporters and ion channels that play an indispensable role in metabolite trafficking have evolved to operate in Earth's gravity. Dysregulation of the transportome expression profile at normogravity not only affects homeostasis along with drug uptake and distribution but also plays a key role in the pathogenesis of diverse localized to systemic diseases including cancer. The profound physiological and biochemical perturbations experienced by astronauts during space expeditions are well-documented.

Profiling solute-carrier transporters in key metabolic tissues during the postpartum evolution of mammary epithelial cells from nonsecretory to secretory.

Modifications in the abundance of solute-carrier (SLC) transcripts in tandem with adjustments in genes-associated with energy homeostasis during the postpartum transition of the mammary epithelial cells (MEC) from nonsecretory to secretory is pivotal for supporting milk synthesis. The goal of this study was to identify differentially expressed SLC genes across key metabolic tissues between late pregnancy and onset of lactation. Total RNA was isolated from the mammary, liver, and adipose tissues collected from rat dams on of pregnancy (P20) and of lactation (L1) and gene expression was measured with Rat 230 2.

Transcriptomes reveal alterations in gravity impact circadian clocks and activate mechanotransduction pathways with adaptation through epigenetic change.

Few studies have investigated the impact of alterations in gravity on mammalian transcriptomes. Here, we describe the impact of spaceflight on mammary transcriptome of late pregnant rats and the effect of hypergravity exposure on mammary, liver, and adipose transcriptomes in late pregnancy and at the onset of lactation. RNA was isolated from mammary collected on pregnancy day 20 from rats exposed to spaceflight from days 11 to 20 of gestation.

Homeorhetic adaptation to lactation: comparative transcriptome analysis of mammary, liver, and adipose tissue during the transition from pregnancy to lactation in rats.

Tissue-specific shifts in a dam's metabolism to support fetal and neonatal growth during pregnancy and lactation are controlled by differential expression of regulatory genes. The goal of this study was to identify a more detailed cohort of genes in mammary, liver, and adipose tissue that are transcriptionally controlled during the pregnancy to lactation evolution and explore the relationship of these genes to core clock genes. Total RNA was isolated from mammary, liver and adipose tissues collected from rat dams on day 20 of pregnancy (P20) and day 1 of lactation (L1) and gene expression was measured using Rat 230 2.

The characterization of DNA methylation-mediated regulation of bovine placental lactogen and bovine prolactin-related protein-1 genes.

Background: Bovine trophoblast binucleate cells (BNC) express a plethora of molecules including bovine placental lactogen (bPL, gene name is bCSH1) and bovine prolactin-related protein-1 (bPRP1). BCSH1 and bPRP1 are members of the growth hormone (GH)/prolactin (PRL) gene family, which are expressed simultaneously in BNC and are central to placentation and the progression of pregnancy in cattle. However, there is a paucity of information on the transcriptional regulatory mechanisms of both the bCSH1 and bPRP1 genes.

Lipogenesis impaired in periparturient rats exposed to altered gravity is independent of prolactin and glucocorticoid secretion.

Perturbed prolactin (PRL) secretion and concomitant downregulation of PRL receptor (PRLR) in periparturient dams exposed to altered gravity are linked to aberrant lipogenesis and reduced neonatal survival. PRL and glucocorticoids (GC) are known to modulate PRLR expression. We hypothesized that improving levels of PRLR would mitigate the increased gravity [hypergravity (HG)]-induced effects of impaired mammary lipogenesis and increase neonatal survival.

Identification of novel bovine cumulus cell molecular markers predictive of oocyte competence: functional and diagnostic implications.

The present study was undertaken to discover molecular markers in bovine cumulus cells predictive of oocyte competence and to elucidate their functional significance. Differences in RNA transcript abundance in cumulus cells harvested from oocytes of adult versus prepubertal animals (a model of poor oocyte quality) were identified by microarray analysis. Four genes of interest encoding for the lysosomal cysteine proteinases cathepsins B, S, K, and Z and displaying greater transcript abundance in cumulus cells surrounding oocytes harvested from prepubertal animals were chosen for further investigation.

Tissue-specific variation in expression of prolactin receptor gene subtypes in hypergravity-exposed rats.

Prolactin (PRL) effects are mediated by membrane receptors (PRLR) of which the long (PRLR-L) and short form (PRLR-S) predominate. Our objective was to compare the distribution pattern of PRLR-L and PRLR-S transcripts and their ratio in adipose (AD), liver (LV), mammary (MG) and pituitary (PG) tissues of stationary (SC, n = 8) and hypergravity (HG, n = 8) exposed periparturient rats. Pregnant rats were exposed to 2 g force from day 11 of gestation (G11) through post partum day 1 (P1).

JY-1, an oocyte-specific gene, regulates granulosa cell function and early embryonic development in cattle.

Oocyte-specific gene products play a key role in regulation of fertility in mammals. Here, we describe the discovery, molecular characterization, and function of JY-1, a bovine oocyte-expressed gene shown to regulate both function of ovarian granulosa cells and early embryogenesis in cattle and characteristics of JY-1 loci in other species. The JY-1 gene encodes for a secreted protein with multiple mRNA transcripts containing an identical ORF but differing lengths of 3' UTR.

Gene expression and maintenance of pregnancy in bovine: roles of trophoblastic binucleate cell-specific molecules.

Cell to cell interaction plays a pivotal role in the regulation of placentogenesis and exchange of stage-specific developmental signals between the fetal and maternal units. Specifically, these interactions are paramount for programmed fetal growth, maternal adaptation to pregnancy and coordination of parturition. However, little is known about the precise regulation of placentation and maintenance of gestation in cattle.

Functional genomics studies of oocyte competence: evidence that reduced transcript abundance for follistatin is associated with poor developmental competence of bovine oocytes.

Poor oocyte competence contributes to infertility in humans and livestock species. The molecular characteristics of such oocytes are generally unknown. Objectives of the present studies were to identify differences in RNA transcript abundance in oocytes and early embryos associated with reduced oocyte competence and development to the blastocyst stage.

Novel algorithm for transcriptome analysis.

A growing body of evidence implicates the oocyte as a key regulator of ovarian folliculogenesis and early embryonic development. We have screened bovine cDNA microarrays (containing expressed sequence tags representing >15,000 unique genes) with Cy3- and Cy5-labeled cDNA derived from bovine oocyte samples collected at two different stages of meiotic maturation (germinal vesicle vs. metaphase II; n = 3 samples per group).

Quantitative analysis of messenger RNA abundance for ribosomal protein L-15, cyclophilin-A, phosphoglycerokinase, beta-glucuronidase, glyceraldehyde 3-phosphate dehydrogenase, beta-actin, and histone H2A during bovine oocyte maturation and early embryogenesis in vitro.

Real-time reverse transcription PCR has greatly improved the ease and sensitivity of quantitative gene expression studies. However, measurement of gene expression generally requires selection of a valid reference (housekeeping gene) for data normalization to compensate for inherent variations. Given the dynamic nature of early embryonic development, application of this technology to studies of oocyte and early embryonic development is further complicated due to limited amounts of starting material and a paucity of information on constitutively expressed genes for data normalization.

Validation and application of a high fidelity mRNA linear amplification procedure for profiling gene expression.

The need for microgram quantities of RNA for microarray experiments has hindered application of this novel technology in cell types/tissue samples with limited abundance of RNA. In this study, potential application of T7-based linear RNA amplification was investigated for use in gene expression profiling experiments where starting material is limited. Yield and integrity of amplified antisense RNA (aaRNA), microarray hybridization intensities, and fidelity of differential gene expression detected were determined for arrays generated for unamplified versus amplified RNA from the same homogenous starting pools.

Quantitative analysis throughout pregnancy of placentomal and interplacentomal expression of pregnancy-associated glycoproteins-1 and -9 in the cow.

The multigenic pregnancy-associated glycoproteins (PAG) exhibit spatially and temporally distinct pattern across gestation in the bovine. The majority of the bovine bPAG are localized to the binucleate cells (BNC) while some are expressed throughout the trophectoderm. Bovine (b)PAG-1 and -9 are both localized to the BNC but are differentially transcribed.

Expression of trophoblast cell-specific pregnancy-related genes in somatic cell-cloned bovine pregnancies.

We compared the expression of bovine prolactin-related protein-1 (bPRP-1), placental lactogen (bPL), and pregnancy-associated glycoproteins-1 (bPAG-1) and -9 (bPAG-9) genes in artificially inseminated (AI) and nuclear transferred (NT) cows during the first trimester of gestation using real-time reverse transcription-polymerase chain reaction and in situ hybridization. Placentomal (cotyledonary, caruncular) and interplacentomal (intercotyledonary, intercaruncular) tissues of AI and NT cows carrying either motile (M) or immotile (IM) fetuses were examined. Transcripts for bPL and bPAG-9 were lower (P < 0.

Characterization of gene expression profiles in early bovine pregnancy using a custom cDNA microarray.

Gene expression analysis comparing nonpregnant with pregnant bovine uteri, including placenta, was performed with a custom cDNA microarray containing 1,933 independent genes. These genes were classified into six categories according to biological function, as follows: cell and tissue structural dynamics (108 genes), intercellular communication (221), intracellular metabolism (265), cell cycle and apoptosis (26), regulation of gene expression (113), expressed sequence tag (EST) and function unknown (617), and uncomplemented genes (583 clones). This array possessed bovine placental/endometrial specificity, as it included many pregnancy-specific molecules, such as pregnancy-associated glycoprotein-1 (PAGs), placental lactogen (PLs), and prolactin-related protein-1 (PRPs).

Implantation and placental development in somatic cell clone recipient cows.

Successful somatic cloned animal production has been reported in various domesticated species, including cattle; however, it is associated with a high rate of pregnancy failure. The low cloning yield could possibly arise from either an abnormal and/or poorly developed placenta. In comparison to control cows, fewer placentomes were found in somatic cell nuclear recipient (NT) cows at day 60 of gestation, suggesting a retardation of fetal/placental growth in these animals.

Plasma steroid profiles following follicle-stimulating hormone or equine chorionic gonadotropin injection in cows chronically treated with gonadotropin-releasing hormone agonist.

Plasma steroid profiles following follicle-stimulating hormone (FSH) or equine chorionic gonadotropin (eCG) injection were studied in chronically gonadotropin releasing hormone agonist (GnRH-A)-treated cows. Follicular development and irINH secretion were stimulated by FSH or eCG injection. The plasma concentrations of estradiol-17 beta (E(2)) and testosterone (T) were markedly increased following eCG injection.