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At least 523 records · Page 29Linked to original sources
PubMed1992

Protein kinase-C activation increases the quantity and poly(A) tail length of corticotropin-releasing hormone messenger RNA in NPLC cells.

We have studied the effect of protein kinase-C activation on the regulation of CRH gene expression in the human hepatoma cell line NPLC/PRF/5 (NPLC), the only cell line known to express the endogenous CRH gene. Incubation of NPLC cells with 100 nM 12-O-tetradecanoyl phorbol 13-acetate (TPA), a phorbol ester that activates protein kinase-C, resulted in a rapid (1-h) and prolonged (72-h) increase in CRH mRNA levels, with the maximum increase of 16-fold observed at 24 h. In addition, TPA treatment increased the size of CRH mRNA by approximately 100 nucleotides. This size increase, which was blocked by protein synthesis inhibitors, occurred within 1 h of TPA addition and lasted at least 8 h, with a return toward the baseline size by 24 h. Structural analysis of CRH mRNA revealed two poly(A) addition sites and, as found in human placenta, multiple transcription start sites. The increase in CRH mRNA size was not due to changes in the sites of either transcription initiation or poly(A) addition, but, rather, to a 3-fold increase in the length of the poly(A) tail itself. The ability of TPA to increase CRH mRNA levels in NPLC cells suggests that the protein kinase-C second messenger pathway may be involved in the physiological regulation of CRH gene expression. Increases in CRH mRNA poly(A) tail length potentially may influence CRH mRNA stability or translatability and, thus, may represent a general mechanism by which the protein kinase-C pathway can influence gene expression.

Anisomycin↗
PubMed2003

[Detection of hantaan virus from gamasid mite and chigger mite by molecular biological methods].

OBJECTIVE: To study the proliferation and location of hantaan virus (HV) in gamasid mites and chigger mites. METHODS: HV RNA in gamasid mites and chigger mites were detected by reverse transcription, polymerase chain reaction (RT- PCR) and in situ hybridization. RESULTS: The smallest quantity of mite from which HV RNA could be detected was 5 mites group. The titers of -and proliferated in mites HV RNA could be found in ovary cells and dug cells of gamasid mites and chigger mites by in situ hybridization. CONCLUSIONS: The results showed that HV could be trans-stadially transmitted and proliferated in mites, and HV always located in ovary and dug organs of mites. These results provide direct evidence at molecular level for the role of gamasid mites and chigger mites as vectors in transmission of HV.

Animals↗
PubMed1978

Changes in cellular concentration of DNA-dependent RNA polymerases A and B during regeneration of rat liver.

1. DNA-dependent RNA polymerases A and B were solubilized from rat liver nuclei at different intervals after partial hepatectomy, and chromatographed on DEAE-Sephadex A-25. Activity of the solubilized RNA polymerases remained unchanged till 6 h after hepatectomy, then started to increase reaching a maximum (350% and 150% of control for the A and B enzyme, respectively) at the 18th hour of regeneration, and was still high at the 36th hour of regeneration. 2. RNA polymerases A and B were extracted and extensively purified from the nuclei of normal and regenerating rat liver. No marked differences in the specific activities between the analogous purified enzymes from normal and regenerating liver were observed, thus the increase in RNA polymerase activities (especially marked in the case of enzyme A) observed after partial hepatectomy is probably due to a real increase in the quantities of enzymes. 3. Concentration of RNA polymerase A in hepatocyte increases from 1.3 x 10(4) (normal liver) to 7.5 x 10(4) (18 h after hepatectomy) molecules per haploid genome. The concentration of polymerase B increases from 3.4 x 10(4) to 5.5 x 10(4) molecules per haploid genome, respectively.

Ammonium Sulfate↗
PubMed1997

Proteome research: complementarity and limitations with respect to the RNA and DNA worlds.

A methodological overview of proteome analysis is provided along with details of efforts to achieve high-throughput screening (HTS) of protein samples derived from two-dimensional electrophoresis gels. For both previously sequenced organisms and those lacking significant DNA sequence information, mass spectrometry has a key role to play in achieving HTS. Prototype robotics designed to conduct appropriate chemistries and deliver 700-1000 protein (genes) per day to batteries of mass spectrometers or liquid chromatography (LC)-based analyses are well advanced, as are efforts to produce high density gridded arrays containing > 1000 proteins on a single matrix assisted laser desorption ionisation/time-of-flight (MALDI-TOF) sample stage. High sensitivity HTS of proteins is proposed by employing principally mass spectrometry in an hierarchical manner: (i) MALDI-TOF-mass spectrometry (MS) on at least 1000 proteins per day; (ii) electrospray ionisation (ESI)/MS/MS for analysis of peptides with respect to predicted fragmentation patterns or by sequence tagging; and (iii) ESI/MS/MS for peptide sequencing. Genomic sequences when complemented with information derived from hybridisation assays and proteome analysis may herald in a new era of holistic cellular biology. The current preoccupation with the absolute quantity of gene-product (RNA and/or protein) should move backstage with respect to more molecularly relevant parameters, such as: molecular half-life; synthesis rate; functional competence (presence or absence of mutations); reaction kinetics; the influence of individual gene-products on biochemical flux; the influence of the environment, cell-cycle, stress and disease on gene-products; and the collective roles of multigenic and epigenetic phenomena governing cellular processes. Proteome analysis is demonstrated as being capable of proceeding independently of DNA sequence information and aiding in genomic annotation. Its ability to confirm the existence of gene-products predicted from DNA sequence is a major contribution to genomic science. The workings of software engines necessary to achieve large-scale proteome analysis are outlined, along with trends towards miniaturisation, analyte concentration and protein detection independent of staining technologies. A challenge for proteome analysis into the future will be to reduce its dependence on two-dimensional (2-D) gel electrophoresis as the preferred method of separating complex mixtures of cellular proteins. Nonetheless, proteome analysis already represents a means of efficiently complementing differential display, high density expression arrays, expressed sequence tags, direct or subtractive hybridisation, chromosomal linkage studies and nucleic acid sequencing as a problem solving tool in molecular biology.

Animals↗
PubMed1973

Studies of nondefective adenovirus 2-simian virus 40 hybrid viruses. V. Isolation of additional hybrids which differ in their simian virus 40-specific biological properties.

Four new nondefective adenovirus 2 (Ad2)-simian virus 40 (SV40) hybrid viruses have been isolated. Although these viruses (designated Ad2(+)ND(2), Ad2(+)ND(3), Ad2(+)ND(4), and Ad2(+)ND(5)) were clonal derivatives of the same Ad2-SV40 hybrid population, they differ significantly from each other and from the previously isolated nondefective hybrid, Ad2(+)ND(1), in their biological properties or in the amount of SV40-specific RNA induced during lytic infection.Like Ad2(+)ND(1), Ad2(+)ND(2), and Ad2(+)ND(4) pass serially in both human embryonic kidney (HEK) and primary African green monkey kidney cells. In contrast, Ad2(+)ND(3) and Ad2(+)ND(5) pass serially only in HEK cells. Ad2(+)ND(2) is like Ad2(+)ND(1) in that it induces the SV40 U antigen, but not SV40 T antigen; however, in contrast to the perinuclear SV40 antigen induced by Ad2(+)ND(1), the SV40 antigen induced by Ad2(+)ND(2) is located peripherally in the cytoplasm as well as in the perinuclear region of infected cells. Ad2(+)ND(4) induces both the SV40 T and U antigens. Ad2(+)ND(3) and Ad2(+)ND(5) do not induce serologically detectable SV40 antigens and are distinguished from each other on the basis of the relative quantities of SV40-specific RNA which they induce. The induction of different SV40-specific functions suggests the incorporation of different segments of SV40 DNA within the genomes of the respective hybrid viruses.

Adenoviridae↗
PubMed1987

Regulation of the expression of tissue inhibitor of metalloproteinases and collagenase by retinoids and glucocorticoids in human fibroblasts.

The regulation of the expression of interstitial collagenase and tissue inhibitor of metalloproteinases (TIMP) was examined in response to both retinoid compounds and glucocorticoids. Effective retinoids induced a dose-dependent, specific increase in the production of TIMP of approximately two- to threefold by monolayer cultures of human fibroblasts derived from various tissues, while simultaneously causing a decrease in collagenase secretion of similar magnitude. These effects were apparent by 8-12 h in culture and disappeared within 24 h after the withdrawal of retinoid compounds. The retinoid effect on TIMP production was mediated via an increased biosynthesis of new inhibitor protein. Similarly, increased steady state levels of TIMP messenger RNA (mRNA) accompanied by decreased quantities of collagenase mRNA were demonstrated, suggesting transcriptional control of the retinoid action. The data suggest that retinoids co-regulate the expression of collagenase and TIMP, and do so in an inverse manner. Dexamethasone caused a dose-dependent, specific decrease in collagenase production without altering the biosynthesis of TIMP. These findings were paralleled by a marked reduction in collagenase mRNA, without any accompanying change in TIMP mRNA. Therefore, TIMP and collagenase expression appear to be independently modulated by glucocorticoids.

Cell Line↗
PubMed1994

Transfer RNA analysis during the reproductive cycle of a freshwater teleost, H. fossilis.

Transfer RNA was analyzed qualitatively as well as quantitatively from ovaries of the fresh water teleost Heteropneustes fossilis for twelve months. The tRNA samples were found to be pure and devoid of any high molecular weight RNA or DNA contaminations. The quantity of tRNA as well as its biological activity, assayed by in vitro aminoacylation using homologous aminoacyl tRNA synthetases, were found to be higher during resting and preparatory (pre-vitellogenic) phases, i.e. from November to March, as compared to vitellogenic and spawning phases of the fish, i.e. from April to October. The highest tRNA pool and its activity was found in the month of February, which coincides with the early preparatory phase. The results indicate that the accumulation of active tRNA starts in the resting phase. Such an accumulation of tRNA may be a part of the enrichment of mature eggs with complete translational machinery before ovulation in order to cope with the high rate of protein synthesis after fertilization.

Amino Acyl-tRNA Synthetases↗
PubMed1976

Polyadenylic acid content and electrophoretic behavior of in vitro released RNA's in chemical carcinogenesis.

Cytoplasmic RNA from control and thioacetamide-intoxicated rat livers was compared with regard to components separated by polyacrylamide electrophoresis and for the proportion containing polyadenylic acid segments. A further comparison was made with the RNA's released from rat liver nuclei in vitro. Exposure in vivo to thioacetamide was associated with more cytoplasmic RNA's with migrations of 9 to 16 S and with both an acute and prolonged increase in the relative quantity of polyadenylic acid-containing polyribonucleotides. Incubation of control nuclei in vitro was associated with a leakage of approximately 1 to 2% of nuclear RNA with a major migration band at 9 S. Addition of adenosine 5'-triphosphate increased the transport 20-fold, and 9 and 16 S species were transported as well as a 4 S group. Following exposure to thioacetamide, an enhanced "leakiness" released 9 S RNA. Addition of adenosine 5'-triphosphate doubled the quantity of released RNA, which consisted of 9 and 4 S species. Both leaked and adenosine 5'-triphosphate-transported RNA's contained polyadenylic acid segments in roughly 20% of the macromolecules. These studies extend the observation of less stringent control of RNA release and transport in carcinogen exposure and suggest the potential usefulness of the in vitro release system for assaying cellular regulatory phenomena.

Acetamides↗
PubMed2005

Expression cloning screening of a unique and full-length set of cDNA clones is an efficient method for identifying genes involved in Xenopus neurogenesis.

Functional screens, where a large numbers of cDNA clones are assayed for certain biological activity, are a useful tool in elucidating gene function. In Xenopus, gain of function screens are performed by pool screening, whereby RNA transcribed in vitro from groups of cDNA clones, ranging from thousands to a hundred, are injected into early embryos. Once an activity is detected in a pool, the active clone is identified by sib-selection. Such screens are intrinsically biased towards potent genes, whose RNA is active at low quantities. To improve the sensitivity and efficiency of a gain of function screen we have bioinformatically processed an arrayed and EST sequenced set of 100,000 gastrula and neurula cDNA clones, to create a unique and full-length set of approximately 2500 clones. Reducing the redundancy and excluding truncated clones from the starting clone set reduced the total number of clones to be screened, in turn allowing us to reduce the pool size to just eight clones per pool. We report that the efficiency of screening this clone set is five-fold higher compared to a redundant set derived from the same libraries. We have screened 960 cDNA clones from this set, for genes that are involved in neurogenesis. We describe the overexpression phenotypes of 18 single clones, the majority of which show a previously uncharacterised phenotype and some of which are completely novel. In situ hybridisation analysis shows that a large number of these genes are specifically expressed in neural tissue. These results demonstrate the effectiveness of a unique full-length set of cDNA clones for uncovering players in a developmental pathway.

Animals↗
PubMed1995

Comparison of base inclination of ribo-GC and deoxyribo-GC polymers, and synthesis of poly(rGrC)-poly(rGrC).

The inclination angle between the base normal and the helix axis, and the axes around which the bases incline, are measured for ribo-GC polymers in buffer by using flow linear dichroism (LD), and compared to measurements for deoxyribo-GC polymers in buffer and under dehydrating conditions. A new method is designed to synthesize poly(rGrC)-poly(rGrC), which is not available commercially, in large quantities. The LD of this RNA reveals inclination angles that are similar to the B-form DNA in buffer, although the axes are different. The CD of poly(dGdC)-poly(dGdC) under the dehydrating conditions is similar to poly(rGrC)-poly(rGrC), indicating it is in the A form, and the LD gives larger inclination angles than either the B form or the corresponding RNA. Poly(dG)-poly(dC) is in the A form in buffer. Comparison among poly(rG)-poly(rC) in buffer, and poly(dG)-poly(dC) in buffer under dehydrating conditions, reveals similar inclination angles and axes, although the LD shows that the DNA has the largest inclination angles. Except for poly(rGrC)-poly(rGrC), which has a unique reduced dichroism, all the axes for G are similar, as are the axes for C.

Circular Dichroism↗
PubMed1998

Characterization of the mevalonate kinase 5'-untranslated region provides evidence for coordinate regulation of cholesterol biosynthesis.

Using a probe derived from the 5'-untranslated region of the human mevalonate kinase (MK) cDNA, we screened a lambda gt 11 genomic library and obtained a single clone containing the 5' untranslated region of the gene. Nucleotide sequencing identified several putative regulatory elements, including two Sp1 (GC box) elements and a CCAAT box. A canonical TATA box was not detected. Directly adjacent to one Sp1 element was a sterol regulatory element (SRE), 5'-CACCCCAG-3', which was a 7/8 base pair match to the consensus sequences identified in the genes encoding 3-hydroxy-3-methyl-glutaryl-coenzyme A synthase and reductase, and the LDL receptor. There was no Sp1 element upstream of the SRE. Northern blot analysis in human CRL1508T cells revealed that quantities of MK poly A+ RNA increased for cells grown in the presence of lipid-deficient calf serum, and further increased upon addition of 1 microM lovastatin. Primer extension analysis with human poly A+ RNA suggested at least 4 transcription initiation sites downstream from the CCAAT box. To assess sterol responsiveness of transcription initiation, a 1.4 kb genomic fragment upstream of the translational start site was fused to the pSV2cat vector for transient expression in COS-7 cells, with chloramphenicol acetyltransferase (CAT) as the reporter gene. This construct demonstrated modest levels of CAT expression which was induced > 2-fold when cells were grown in lipoprotein-deficient calf serum. Our data provide further evidence for coordinate regulation of cholesterol biosynthesis in response to sterol.

Animals↗
PubMed1991

Epstein-Barr virus BHRF1 gene but not the cellular protooncogene bcl-2 is expressed in ataxia-telangiectasia lymphoblastoid lines.

The expression of both the Epstein-Barr virus (EBV) ORF BHRF1 and the cellular protooncogene bcl-2 was studied in EBV-transformed lymphoblastoid B cells from patients with the human genetic disorder ataxia-telangiectasia (A-T). Using the Northern blot technique, it was found that the pattern of transcription of the BHRF1 gene in A-T lymphoblastoids resembled that in EBV-transformed normal lymphoblastoid lines and Burkitt lymphoma (BL) lymphocytes. However, the 1.5-kb mature BHRF1 mRNA species present in normal lymphoblastoid cells and in BL cells was not found in the A-T lymphoblastoid cell lines. Treatment of the A-T lymphoblastoid lines with phorbol ester caused changes in the pattern of the synthesis and quantity of BHRF1-related RNA transcripts. The bcl-2 protooncogene probe did not detect bcl-2-related mRNA in the A-T lymphoblastoid lines.

Ataxia Telangiectasia↗
PubMed1994

PAF and TNF increase the precursor of NF-kappa B p50 mRNA in mouse intestine: quantitative analysis by competitive PCR.

NF-kappa B, a nuclear transcription factor, is involved in the regulation of inflammatory cytokines. We have previously reported that PAF and TNF induce intestinal injury in rats and mice and the interaction of TNF and PAF probably plays a central role in its pathogenesis. In the present study, we developed a competitive PCR method to quantitate the transcripts of NF-kappa B p50/p105 gene, and investigated the effects of PAF and TNF on p50/p105 gene expression in the small intestine of C3H/HeN mice - p105 is the precursor of the p50 subunit of NF-kB. We found that NF-kappa B p50/p105 gene is constitutively expressed in the normal small intestine in small quantities (7.05 +/- 1.04 attomol/micrograms total RNA). PAF at a dose (1 microgram/kg) causing no systemic changes (e.g., hypotension, hemoconcentration), markedly increased intestinal p50/p105 transcripts within 30 min. TNF, at dose (1 mg/kg) also insufficient to induce systemic changes, increased intestinal p50/p105 gene expression, although its effect was much slower than PAF. The effect of TNF was not blocked by WEB 2086, a PAF antagonist. Our results indicate that both PAF and TNF stimulate the expression of NF-kappa B p50/p105 in vivo. However, the mechanisms of their respective actions are probably different.

Animals↗
PubMed1996

Slow fluorescent indicators of membrane potential: a survey of different approaches to probe response analysis.

Basic tenets related to the use of three main classes of potentiometric redistribution fluorescent dyes (carbocyanines, oxonols, and rhodamines) are discussed in detail. They include the structure/function relationship, formation of nonfluorescent (H-type) and fluorescent (J-type) dimers and higher aggregates, probe partitioning between membranes and medium and binding to membranes and intracellular components (with attendant changes in absorption and emission spectra, fluorescence quantum yield and lifetime). The crucial importance of suitable probe-to-cell concentration ratio and selection of optimum monitored fluorescence wavelength is illustrated in schematic diagrams and possible artifacts or puzzling results stemming from faulty experimental protocol are pointed out. Special attention is paid to procedures used for probe-response calibration (potential clamping by potassium in the presence of valinomycin, use of gramicidin D in combination with N-methylglucamine, activation of Ca-dependent K-channels by A23187, the null-point technique). Among other problems treated are dye toxicity, interaction with mitochondria and other organelles, and possible effects of intracellular pH and the quantity of cytosolic proteins and/or RNA on probe response. Individual techniques using redistribution dyes (fluorescence measurements in cuvettes, flow cytometry and microfluorimetry of individual cells including fluorescence confocal microscopy) are discussed in terms of reliability, limitations and drawbacks, and selection of suitable probes. Up-to-date examples of application of slow dyes illustrate the broad range of problems in which these probes can be used.

Animals↗
PubMed2006

Expression of syndecan-1 (CD138) in nasopharyngeal carcinoma is correlated with advanced stage and poor prognosis.

Nasopharyngeal carcinoma (NPC) is an important Epstein-Barr virus-associated head and neck malignancy in Taiwan. Syndecan-1 (CD138) is involved in growth, differentiation, invasiveness, and metastatic potential of certain tumors, but its expression in NPC has never been studied. In this study, detection of expression of syndecan-1 protein and Epstein-Barr virus-encoded latent membrane protein-1 (LMP-1) in primary, recurrent, and metastatic NPC specimens in paraffin sections was performed by immunohistochemistry. The quantity of syndecan-1 messenger RNA in tumor cells was investigated by real-time reverse transcriptase polymerase chain reaction using laser capture microdissection. The results of immunohistochemical staining of syndecan-1 and LMP-1 correlated with clinicopathologic features of NPC. Eighteen (20.9%) of 86 primary, 9 (24.3%) of 37 recurrent, and 15 (44.1%) of 34 metastatic NPC samples were positive for syndecan-1, and 37 (43.0%) primary, 18 (48.6%) recurrent, and 12 (35.3%) metastatic samples were positive for LMP-1 expression. Primary NPCs with syndecan-1 protein expression were more frequently associated with advanced clinical stages and worse 5-year survival rates than those without (P = .015 and P = .0021, respectively). Conversely, the LMP-1 expression did not correlate with tumor stage or prognosis but occurred more often in nonkeratinizing carcinoma than keratinizing squamous cell carcinoma (unpublished observation). The inverse expression of syndecan-1 and LMP-1 was noted in primary NPC specimens (total 4/18 versus 35/68, P = .05). The reverse transcriptase polymerase chain reaction revealed low syndecan-1 messenger RNA levels in both primary and metastatic NPC. In conclusion, the protein expression of syndecan-1 in 21% of primary NPC was associated with advanced disease and poor prognosis, and the protein expression correlated with transcription levels.

Biomarkers, Tumor↗
PubMed1999

Quantitation of equine cytokine mRNA expression by reverse transcription-competitive polymerase chain reaction.

A reverse transcription-competitive polymerase chain reaction (RT-cPCR) method was developed to quantitate equine interleukin (IL)-1alpha, IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12 p35, IL-12 p40, interferon-gamma (INF-gamma), tumor necrosis factor-alpha (TNF-alpha), and beta-actin mRNA expression. Using primers based on equine-specific sequences, these cytokines could be detected in concanavalin A-stimulated peripheral blood mononuclear cells. The specificity of the amplified product was confirmed by sequencing. For each cytokine, the assay was made quantitative by generating competitor DNA fragments (mimic) containing the same primer template as a equine cytokine, but differing in size to make them distinguishable on an agarose gel. Serial dilutions of the mimic were added to PCR reactions containing constant amount of equine cDNA. Following gel electrophoresis and ethidium bromide staining, densitometric analysis of the bands corresponding to the target and mimic were used to construct a standard curve from which the amount of target cDNA was derived. Quantitation of IL-6 gene expression from a cDNA sample on four different days gave a coefficient of variation or 6.6%. Sample-to-sample variation in the efficiency of the reverse transcription as well as in the quantity of quality of starting RNA was considerably attenuated by normalizing the results to beta-actin mRNA expression used as a house-keeping gene. Small differences (2-fold) in cytokine mRNA expression were reliably detected. The sensitivity and reproducibility of this technique will make it valuable in following changes in equine cytokine gene expression in vitro and in vivo. In addition, the RT-cPCR technique described will have broad applicability for quantitation of cytokine gene expression in other animal species of veterinary interest.

Actins↗
PubMed2002

Effect of catechin on the activity and gene expression of superoxide dismutase in cultured rat brain astrocytes.

Stroke is one of the major causes of morbidity and mortality in recent. Oxygen free radicals produced during cerebral infarction increases the damage to neurons. Superoxide dismutase (SOD) is the endogenous antioxidant enzyme that can effectively scavenge superoxide radicals. Catechin is a hydrophilic antioxidant usually existed in tea, fruits and vegetables. In the cultured rat brain astrocytes (RBA), the activity of SOD (both Cu, Zn-SOD and Mn-SOD subtypes) was markedly increased by incubation with catechin at low concentration (0.1 microM) for 2 days (short-term) and 7 days (long-term). This stimulatory effect of catechin was not related to the incubating concentration. Similar changes were also observed in the gene expression of SOD in RBA. The increase in quantity of SOD-messenger RNA was remarkable and seemed to be more obvious than the other antioxidants such as vitamin E. This result shows that catechin is an effective antioxidant to increase the activity of SOD in RBA which would be beneficial to neurons subjected to oxygen free radical damage.

Animals↗
PubMedDate not supplied

Production of transgenic rabbits, sheep and pigs by microinjection.

Direct microinjection has been used to introduce foreign DNA into a number of terminally differentiated cell types as well as embryos of several species including sea urchin, Candida elegans, Xenopus, Drosophila and mice. Various genes have been successfully introduced into mice including constructs consisting of the mouse metallothionein-I (MT) promoter/regulator region fused to either the rat or human growth hormone (hGH) structural genes. Transgenic mice harbouring such genes commonly exhibit high, metal-inducible levels of the fusion messenger RNA in several organs, substantial quantities of the foreign growth hormone in serum and enhanced growth. In addition, the gene is stably incorporated into the germ line, making the phenotype heritable. Because of the scientific importance and potential economic value of transgenic livestock containing foreign genes, we initiated studies on large animals by microinjecting the fusion gene, MT-hGH, into the pronuclei or nuclei of eggs from superovulated rabbits, sheep and pigs. We report here integration of the gene in all three species and expression of the gene in transgenic rabbits and pigs.

Animals↗