Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Mouse”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 901 records · Page 50Linked to original sources

Molecular cloning of cDNAs of mouse peptidylarginine deiminase type I, type III and type IV, and the expression pattern of type I in mouse.

Peptidylarginine deiminases (PADs), a group of post-translational enzymes, catalyze the conversion of protein-bound arginine residues to citrulline residues in a calcium ion-dependent manner and are widely distributed in various organs of vertebrates. Although the existence of four isoforms of PAD (types I, II, III, and IV) is reported in rodents, the relative functions of the isoforms with respect to their colocation in the tissues have yet to be explored. In this study, we cloned the full-length cDNA encoding mouse PAD type I by screening a uterine cDNA library and using the RACE method. This cDNA consists of an open reading frame of 1989 bases encoding 662 amino acids (73,823 Da), a 5'-untranslated region of 127 bases and a 3'-untranslated region of 1639 bases. Comparative reverse transcription-PCR and Northern-blot analyses detected PAD type I mRNA only in the epidermis and uterus. Administration of estrogen to adult ovariectomized mice increased the content of PAD type I mRNA in the uterus, providing evidence that its expression is under the control of the sex steroid hormone. We also cloned the full-length cDNAs of mouse PAD type III and type IV by the reverse transcription-PCR and RACE methods. The primary structure of PAD type III contains 664 amino acids (75,098 Da) deduced from the coding region of 1995 bases, and the primary structure of PAD type IV consists of 666 amino acids (74,475 Da) deduced from the coding region of 2001 bases. Comparison of the deduced amino acid sequences of all four isoforms of PAD showed about 50% identity with each other, the 3' regions being highly homologous compared with the 5' regions.

Amino Acid Sequence↗

Mdes, a mouse homolog of the Drosophila degenerative spermatocyte gene is expressed during mouse spermatogenesis.

A new mouse gene Mdes has been identified, which has a significant sequence homology with a Drosophila gene degenerative spermatocyte (des) that is required for the initiation of meiosis in spermatogenesis. The expression pattern of the Mdes transcript during mouse spermatogenesis is similar to that of the des transcript curing Drosophila spermatogenesis. Based on these results, it is proposed that the products of Mdes and des have a phylogenetically conserved role in vertebrate and invertebrate spermatogenesis.

Amino Acid Sequence↗

[Prenatal eyelid development in the hl-mouse--a hairless mutant of the colored wild mouse].

BACKGROUND: A decisive condition for the clarification of malformations and degenerations is knowledge of the pre- and postnatal development. Therefore investigations were undertaken to determine the plan and lay-out of the eye-lids in an hairloss mutant of mouse. MATERIALS AND METHODS: Biomicroscopical and histological investigations were carried out in 51 hl-mice from the 10th day of gestation unto the birth. This particular mouse is a spontaneous hairloss mutant, in which corneal degenerations also occur. RESULTS: On the 11th day of gestation the ectodermal dips may be distinguished, as well as the shoe-lace-like furrows around the eye-ball, which indicate the development of the eyelids. The upper and lower lid are formed by proliferation. The fusion of the eyelids is completed around the 16th day of gestation. DISCUSSION: The eyelid development starts in mice between the 11th and 14th day of gestation. The fusion is completed on day 15-17. The morphogenesis of the eyelid development will be discussed.

Animals↗

Elimination of mouse allergens in the working environment: assessment of individually ventilated cage systems and ventilated cabinets in the containment of mouse allergens.

BACKGROUND: Laboratory animal allergy is an important occupational disease that is preventable by reduction of exposure to mammalian allergens. OBJECTIVE: The purpose of this investigation was to assess the efficacy of safety equipment in containing mouse urinary protein (MUP)--specifically, individually ventilated cage (IVC) systems and class I--type and class II ventilated cabinets. METHODS: Six IVC systems (which are used to house rodents) were operated at positive and negative pressure. Air samples (2 L/min) were collected at the cage front, cage back, air inlet, and air outlet, and the MUP was quantified by immunoassay. The background MUP of the IVC study room was compared with that of rooms where mice were housed conventionally or in isolators. Class I--type cabinets (n = 2) were tested during the disposal of soiled litter. Air samples were positioned on and behind the operator and inside the cabinet (n = 2). Personal samples were collected while scientific procedures were performed in a class II cabinet and in the open. RESULTS: All of the IVC systems contained MUP effectively (>250-fold) when operated at negative pressure. At positive pressure, the "unsealed" IVC racks leaked MUP (1- to 25-fold reduction) but the "sealed" IVC system did not. Class I--type cabinets reduced (10-fold) but did not eliminate exposure during "cleaning out." No MUP was detected when procedures were performed in class II cabinets (protection factor, >10-fold). CONCLUSION: Safety equipment can substantially reduce exposure to mouse allergen. Allergen exposure in holding rooms will be minimized if mice are housed in IVC systems operated at negative pressure or in "sealed" IVC systems at positive pressure. Respiratory protection should be used whenever "unsealed" IVC systems are operated at positive pressure or during "cleaning out" in class I--type cabinets.

Allergens↗

Identification and molecular cloning of Moloney mouse sarcoma virus-specific sequences from uninfected mouse cells.

When uninfected mouse cell DNA is cleaved with restriction endonuclease EcoRI, a DNA fragment of 14.0 kilobases can be identified by hybridization to cloned DNA containing sarcoma specific sequences of Moloney mouse sarcoma virus (M-MSVsrc). The cellular DNA fragment contains the entire M-MSVsrc specific sequences. The 14.0-kilobase EcoRI DNA fragment was cloned in bacteriophage lambda. The sequence organization of a recombinant clone, lambda . MTX-1, was analyzed by restriction endonuclease mapping, nuclease S1 mapping, and electron microscopy. The results indicate that lambda . MTX-1 contains an uninterrupted stretch of 1.0 kilobase similar to that found in the M-MSV genome.

Animals↗

Exogenous expression of mouse interferon gamma cDNA in mouse neuroblastoma C1300 cells results in reduced tumorigenicity by augmented anti-tumor immunity.

To examine the influence of interferon gamma (IFN-gamma) on tumorigenicity, we established constitutively IFN-gamma-producing cell lines from a malignant mouse neuroblastoma, C1300, by retroviral transfer of a mouse IFN-gamma cDNA. The gene-transferred cells generally showed an enhanced high-level expression of the major histocompatibility complex class I antigens at the cell surface and the transcription levels, irrespective of their IFN-gamma-producing potential. Although in vitro cell growth of these cells was unaffected by the IFN-gamma production, their s.c. tumor growth in syngeneic A/J mice was dependent upon levels of IFN-gamma production; tumors induced by a low-producer line grew well at a rate similar to those induced by the parental one, but tumor growth of a high-producer line was strongly suppressed. This apparent tumor suppression was abolished by simultaneous i.p. injection of anti-Lyt2.2 and/or anti-IFN-gamma monoclonal antibodies, and subsequently large tumors of the high producer were generated. Anti-asialoganglioside GM1 antibodies allowed the high-producer line to induce a substantial but only transient tumor growth, whereas other antibodies, such as anti-Lyt2.1, anti-IFN-beta, and anti-activated macrophage, had no such effect. The mice immunized with the high-producer line were resistant to tumor growth of the parental cells but permitted another kind of A/J tumor line, Sa-1, to induce remarkable tumors. These results indicate that the reduced tumorigenicity of the IFN-gamma high-producer line was due to the augmented specific anti-tumor immunity, in which cytotoxic T lymphocytes seemed to play a decisive role, probably as a result of the immunomodulatory effects of the IFN-gamma derived from the tumor.

Animals↗

Epidermal growth factor stimulates mouse placental lactogen I but inhibits mouse placental lactogen II secretion in vitro.

This study was undertaken to determine whether epidermal growth factor (EGF) regulates the secretion of mouse placental lactogen (mPL)-I and mPL-II. Primary cell cultures were prepared from placentas from days 7, 9, and 11 of pregnancy and cultured for up to 5 days. Addition of EGF (20 ng/ml) to the medium resulted in significant stimulation of mPL-I secretion by the second day of culture in cells from days 7 and 9 of pregnancy and significant inhibition of mPL-II secretion by the third or fourth day of culture in cells from days 7, 9, and 11. Dose-response studies carried out with cells from day 7 of pregnancy demonstrated that the minimum concentration of EGF that stimulated mPL-I secretion and inhibited mPL-II secretion was 1.0 ng/ml. EGF did not affect the DNA content of the cells or cell viability, assessed by trypan blue exclusion, nor did it have a general effect on protein synthesis. There are three types of PL-containing giant cells in mouse placental cell cultures: cells that contain either mPL-I or mPL-II and cells that contain both hormones. Immunocytochemical analysis and the reverse hemolytic plaque assay indicated that EGF treatment was accompanied by a significant increase in the number of cells that produce mPL-I, but among the PL cells that contained mPL-I, there was no change in the fraction of cells that contained only mPL-I or the fraction that contained both mPL-I and mPL-II. In contrast, EGF treatment did affect the distribution of mPL-II among PL cells. In control cultures, about 75% of the cells that contained mPL-II also contained mPL-I, but in EGF-treated cultures, all of the cells that contained mPL-II also contained mPL-I. These data suggest that EGF regulates mPL-I and mPL-II secretion at least partly by regulating PL cell differentiation.

Animals↗

A mammalian model for Laron syndrome produced by targeted disruption of the mouse growth hormone receptor/binding protein gene (the Laron mouse).

Laron syndrome [growth hormone (GH) insensitivity syndrome] is a hereditary dwarfism resulting from defects in the GH receptor (GHR) gene. GHR deficiency has not been reported in mammals other than humans. Many aspects of GHR dysfunction remain unknown because of ethical and practical limitations in studying humans. To create a mammalian model for this disease, we generated mice bearing a disrupted GHR/binding protein (GHR/BP) gene through a homologous gene targeting approach. Homozygous GHR/BP knockout mice showed severe postnatal growth retardation, proportionate dwarfism, absence of the GHR and GH binding protein, greatly decreased serum insulin-like growth factor I and elevated serum GH concentrations. These characteristics represent the phenotype typical of individuals with Laron syndrome. Animals heterozygous for the GHR/BP defect show only minimal growth impairment but have an intermediate biochemical phenotype, with decreased GHR and GH binding protein expression and slightly diminished insulin-like growth factor I levels. These findings indicate that the GHR/BP-deficient mouse (Laron mouse) is a suitable model for human Laron syndrome that will prove useful for the elucidation of many aspects of GHR/BP function that cannot be obtained in humans.

Animals↗

Transcriptional regulation of mouse delta-opioid receptor gene. Role of Ikaros in the stimulated transcription of mouse delta-opioid receptor gene in activated T cells.

Delta-opioid receptors (DOR) present on T cells have been shown to mediate the immunomodulatory effects of endogenous and synthetic DOR agonists on T cells. Considerable evidence indicates that there is stimulated transcription of DOR gene in activated T cells, which is correlated with augmented expression of DOR and enhanced capacity of DOR agonists to affect the T-cell's functions. However, the molecular mechanism underlying the stimulated transcription of the DOR gene in activated T cells is still unclear. In the present study, we analyzed a 1.3-kb DNA fragment immediately upstream of the translation start site (-1300 to +1 bp, with the translation start site designated as +1) of the mouse DOR gene in EL-4 cells, a mouse lymphoma T cell line that exhibits enhanced expression of DOR transcripts when activated by phytohemagglutinin. Through both in vivo and in vitro experiments, we have demonstrated that increased binding activity of Ikaros at the Ikaros-binding site (-378 to -374) in the DOR promoter is required for the stimulated transcription of DOR gene in phytohemagglutinin-activated T cells.

Animals↗

The effect of several different anaesthetics on the blood pressure and heart rate of the mouse and on the radiation response of the mouse sarcoma RIF-1.

Several anaesthetics were tested with mice to study: (a) their ability to immobilize the animal; (b) their effect on blood pressure and heart rate; and (c) their effect on the response to X-irradiation of the mouse sarcoma RIF-1. All anaesthetics which produced adequate immobilization also caused a fall in blood pressure and some radioprotection of tumour cells. Physical restraint of the tumour-bearing leg of an unanaesthetized mouse also caused radioprotection of the tumour cells.

Anesthetics↗

The effect of relative humidity on mouse allergen levels in an environmentally controlled mouse room.

To determine the effect of humidity on the levels of the mouse allergen Mus m 1, an experimental animal room was constructed to control environmental variables. The sex, strain, age, and number of mice was constant in the room, so that the average daily production of Mus m 1 would not vary greatly. Six different levels of relative humidity from 15% to 65% were maintained for a minimum of a week each. Daily collections of airborne particulates were eluted from filters and Mus m 1 content measured by immunological assay. Increasing relative humidity caused a decrease in Mus m 1 levels from a high of 3 ng/m3 at 15% humidity to a low of 0.5 ng/m3 at 65% humidity. Thus, reduction of airborne allergen levels can be achieved by careful attention to humidity control, especially during the winter heating season when humidity levels may be low. This experimental room can be used to measure the effect of other variables such as ventilation rate, caging, bedding, and work practices on the levels of mouse allergen in an animal facility.

Allergens↗

Immune responses in vitro. IV. Suppression of primary M, G, and A plaque-forming cell responses in mouse spleen cell cultures by class-specific antibody to mouse immunoglobulins.

The suppressive effects of monospecific goat anti-mouse globulins on primary immunoglobulin class-specific plaque-forming cell responses in mouse spleen cell cultures were investigated. Anti-micro suppressed responses in all immunoglobulin classes, whereas anti-gamma(1) and anti-gamma(2) suppressed the gamma(1) and gamma(2) responses but not gammaM or gammaA responses, and anti-gammaA suppressed only gammaA responses. The mechanism of action of the anti-micro was studied in detail because of its suppression of responses in all immunoglobulin classes. The anti-micro was specific for micro-chain determinants; its activity was dose dependent, but was not mediated by killing cells with surface micro-chain determinants. Free gammaM but not gammaG myeloma proteins in solution effectively competed with micro-bearing cells for the anti-micro. An excess of anti-micro was necessary in the cultures for 48 hr to insure complete suppression of 5-day responses. However, after removal of excess anti-micro at 48 hr, responses could be stimulated by newly added antigen in cultures where incubation was prolonged to 7 days. Anti-micro was most effective when added at the initiation of cultures and had no suppressive effect when added at 48 hr. Excess antigen did not effectively compete with anti-micro for antigen receptors. Precursors of antibody-forming cells were shown to be the cell population where the suppressive activity of anti-micro was mediated. The experiments suggest that anti-micro combines with micro-chain determinants in antigen-specific receptors on the surfaces of antibody-forming cell precursors, prevents effective stimulation by antigen and subsequent antibody production. To explain suppression of responses in all Ig classes by anti-micro, several models were proposed. It is not possible to determine from the data whether stimulation of precursor cells with gammaG or gammaA receptors requires concommitant stimulation of separate cells with only gammaM receptors, or whether cells bearing gammaM receptors are precommitted to or differentiate into cells capable of synthesis of other Ig classes, or whether receptors of gammaM and another Ig class are present on some virgin precursors or the second Ig receptor appears after antigenic stimulation.

Animals↗

T lymphomagenesis is determined by a dominant host gene thymic lymphoma susceptible mouse-1 (TLSM-1) in mouse models.

Susceptibility to T lymphomas in mice is determined by a number of viral and host genetic factors. We analyzed the types and latent period of lymphomas spontaneously occurring in crosses between AKR/Ms, a T lymphoma-prone mouse strain, and SL/Kh, a pre-B lymphoma-prone strain. The incidence of T lymphomas in the F1 hybrids backcross to SL/Kh as well as F2 generation mice indicated that a dominant host gene thymic lymphoma susceptible mouse-1 (Tlsm-1) of AKR/Ms determined the type of lymphomas to be thymic. Linkage analysis with microsatellite markers assigned Tlsm-1 to the map position 61 cM from centromere of the chromosome 7. Close scrutiny of this region of AKXD recombinant inbred strains for spontaneous T lymphomas revealed the presence of Tlsm-1-like gene most likely between D7MIT71 (map position 62) and D7MIT13 (map position 70). On the other hand, a SL/Kh-derived recessive allele at a major histocompatibility complex (MHC)-linked locus accelerated development of both T and B lymphomas.

Animals↗

The chymase, mouse mast cell protease 4, constitutes the major chymotrypsin-like activity in peritoneum and ear tissue. A role for mouse mast cell protease 4 in thrombin regulation and fibronectin turnover.

To gain insight into the biological role of mast cell chymase we have generated a mouse strain with a targeted deletion in the gene for mast cell protease 4 (mMCP-4), the mouse chymase that has the closest relationship to the human chymase in terms of tissue localization and functional properties. The inactivation of mMCP-4 did not affect the storage of other mast cell proteases and did not affect the number of mast cells or the mast cell morphology. However, mMCP-4 inactivation resulted in complete loss of chymotryptic activity in the peritoneum and in ear tissue, indicating that mMCP-4 is the main source of stored chymotrypsin-like protease activity at these sites. The mMCP-4 null cells showed markedly impaired ability to perform inactivating cleavages of thrombin, indicating a role for mMCP-4 in regulating the extravascular coagulation system. Further, a role for mMCP-4 in connective tissue remodeling was suggested by the inability of mMCP-4 null peritoneal cells to process endogenous fibronectin.

Animals↗

Stable expression of mouse Cyp1a1 and human CYP1A2 cDNAs transfected into mouse hepatoma cells lacking detectable P450 enzyme activity.

Using the mouse hepatoma Hepa-1c1c7 c37 mutant cell line that exhibits negligible benzo[a]pyrene hydroxylase (Cyp1a1) and acetanilide 4-hydroxylase (Cyp1a2) enzyme activities, we developed stable transfectants of plasmids containing the murine Cyp1a1 (cytochrome P(1)450) and the human CYP1A2 (P(3)450) cDNAs. We show that the assay measuring metabolism of ethoxyfluorescein ethyl ester (EFEE) was invaluable in screening large numbers of individual cell lines for high Cyp1a1 enzyme activity. Nine different plasmid constructs containing various combinations of promoter and enhancer sequences were compared, including: the Drosophila heat shock promoter, the mouse mammary tumor virus long terminal repeat (MMTV LTR) carrying the glucocorticoid-responsive element (GRE), enhancer sequences from simian virus 40 (SV40) and herpes simplex virus type 1 (HSV-1), and the aromatic hydrocarbon-responsive domain (AhRD) of the murine Cyp1a1 gene. Interestingly, only those constructs containing the AhRD produced high levels of Cyp1a1 enzyme activity. In contrast, high levels of CYP1A2 activity were obtained with plasmids carrying the HSV-1 enhancer, as well as the AhRD. These studies suggest that the AhRD, which responds to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), provides a post-transcriptional signal necessary for the induction of functional Cyp1a1 enzyme activity. Although untransfected c37 cells exhibit markedly elevated levels of endogenous Cyp1a1 mRNA, the expression of exogenous Cyp1a1 or CYP1A2 enzyme activity in these cells decreases the concentration of this endogenous Cyp1a1 mRNA to negligible levels and restores Cyp1a1 mRNA inducibility by TCDD; these data indicate that the functional product of either the Cyp1a1 gene or the CYP1A2 gene might have a role in an autoregulatory loop controlling the constitutive expression of the Cyp1a1 gene. The cell lines described herein should be valuable in assessing the contribution of these two P450 enzymes to the processes of cytotoxicity, mutagenesis, and carcinogenesis.

Animals↗

Mouse ubiquitous mitochondrial creatine kinase: gene organization and consequences from inactivation in mouse embryonic stem cells.

Individual members of the creatine kinase isoenzyme family (CK; EC 2.7.3.2), which play a prominent role in energy homeostasis, are encoded by four separate nuclear genes. We have isolated and characterized the complete mouse UbCKmit gene, the product of which is ubiquitously expressed and is located in the intermembrane space of mitochondria. Transcription of this gene is initiated at multiple adjacent positions and the region immediately upstream of these sites shares many features with genes encoding housekeeping proteins. These include a high G/C content, absence of TATA and CCAAT motifs, and presence of SP1 and AP2 recognition sequences. In addition, a binding site for HIP1, hormone-responsive elements, and three Mt-motifs, known as boxes shared between nuclear genes encoding mitochondrial proteins, were identified. To study the functional role of the UbCKmit protein, we have inactivated both UbCKmit alleles in mouse embryonic stem (ES) cells. UbCKmit-deficient cells, obtained by consecutive rounds of gene targeting using homologous recombination and drug selection-driven gene conversion events, show no obvious growth disadvantage or abnormal differentiation potential. Activities of mitochondrial cytochrome c oxidase and citrate synthase, as well as the rate of pyruvate oxidation, showed values equal to wild-type cells, indicating a normal aerobic metabolism. Mitochondria of in vivo differentiated knock-out cells were structurally intact, as demonstrated by electron microscopy. Approaches to study the role of the UbCKmit gene further are discussed.

Animals↗

Characterization of an established mouse-human heterohybridoma and its application for production of (mouse-human)-human triple hybridoma secreting human immunoglobulin.

We report the construction of a mouse-human (M-H) heterohybridoma by fusion of the murine myeloma cell line NS-1 and human spleen cells from a 17 week old fetus. The nonsecreting, cloned hybridoma cell line II was resistant to 8-azaguanine (8-AG) and sensitive to hypoxanthine, aminopterin and thymidine (HAT) medium. It grew rapidly in 8-AG containing medium (doubling time 20 hrs.), but did not grow in HAT medium or in non-serum medium. It had a high fusion frequency with human lymphocytes from regional lymph nodes. Five human chromosomes were retained stably for over 6 months by this cell line II. Nine (mouse-human)-human ((M-H)-H) triple hybridomas secreting human IgG 1 or IgM were established by the fusion of this parental cell line II and human lymphocytes from regional lymph nodes. Immunoglobulin secretion was stable and has been maintained for over 8-10 months without recloning in these hybridomas. Secretion of immunoglobulin varies from 2.1-3.0 micrograms/10(6) cells/day, and these hybridomas contain from 3 to 16 human chromosomes, including No. 14. So, this M-H heterohybridoma II is an excellent useful parental cell line for the production of hybridomas secreting human immunoglobulin.

Animals↗