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We have isolated and sequenced cDNA clones of bovine and murine p11 mRNAs. The nonpolyadenylated mRNAs are predicted to be 614 and 600 nucleotides, respectively. The p11 mRNAs both contain a 291 nucleotide open reading frame, preceded by a 5'-untranslated region of 73 nucleotides in bovine p11 mRNA and of 68 nucleotides in murine p11 mRNA. The deduced bovine p11 amino acid sequence is identical to the previously published partial bovine and complete porcine p11 protein sequence except for an additional COOH-terminal lysine residue. The bovine and murine p11 proteins are 92% homologous, whereas at the nucleotide level the conservation is 89% in the coding region and 75% in the 3'-untranslated region. Southern analysis of murine genomic DNA detected a single p11 gene, less than 10 kilobase pairs in size, containing as many as three introns. The p11 gene has been assigned to mouse chromosome 3 by analysis of interspecific hybrid cell panels and recombinant inbred mouse strains. The p11 gene is closely linked to the Xmmv-65 endogenous leukemia virus env gene and the guanylate binding protein-1 gene. Northern analyses of RNAs from mouse tissues and cell lines indicated that p11 mRNA levels vary widely. They are very low in liver, heart, and testes, moderate in brain, spleen, and thymus, and high in kidney, intestine, and lung. Analysis of the same RNA samples for p36 mRNA levels showed that expression of p11 and p36 mRNAs is not always coordinated. Brain and the mouse embryonal carcinoma cell line F9 contain moderate to high levels of p11 mRNA with very low levels of p36 mRNA. Sequence homology between p11 and the S100 proteins, and the serum-induced 2A9 gene product, as well as possible functions of p11 are discussed.  相似文献   
76.
Woodchuck hepatitis virus (WHV), like the related hepatitis B virus, induces in its natural host hepatocellular carcinomas that contain integrated viral sequences. As a first step in determining whether and how the integrated sequences contribute to formation of the tumors in which they are found, we have cloned two such integrations of WHV and have determined their structure by restriction mapping and heteroduplex electron microscopy. The identity of the cloned sequences was confirmed by comparison of restriction sites in the clones with those located by Southern blot analysis of tumor DNA. Viral sequences in both integrations are extensively rearranged, and in neither were all parts of the viral genome represented. In this respect, the behavior of WHV in vivo is similar to that of other DNA tumor viruses that have been studied in vitro. We discuss the implications of these results in relation to possible mechanisms for tumor induction by WHV.  相似文献   
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Summary Three mosquito cell cultures designated as Suitor's clone ofAedes aegypti, Culiseta inornata andAedes vexans were shown to be moth by immunological, karyological, and isozyme analyses. The cells reacted with rabbit antimoth serum but not rabbit antimosquito serum. Chromosome analyses indicated Lepidopteran rather than Dipteran morphology, and three isozyme systems were confirmative. Any one of these assays would be sufficient to indicate that contamination had occurred and could be used as a periodic check for identity of cell cultures. Morphology and growth characteristics are also valid criteria to distinguish between these particular orders of insect cells. These studies were supported by Grant CA-04953-12 from the National Cancer Institute; General Research Support Grant FR-5582 from the National Institues of Health; and Grant-in-Aid Contract M-43 from the State of New Jersey. Recipient of Research Career Award 5-K3-16,749. from the National Institutes of Health.  相似文献   
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Summary Three mosquito cell cultures designated as Suitor's clone ofAedes aegypti, Culiseta inornata, andAedes vexans were shown to be moth by immunological, karyological, and isozyme analyses. The cells reacted with rabbit antimoth serum but not rabbit antimosquito serum. Chromosome analyses indicated Lepidopteran rather than Dipteran morphology, and three isozyme systems were confirmative. Any one of these assays would be sufficient to indicate that contamination had occurred and could be used as a periodic check for identity of cell cultures. Morphology and growth characteristics are also valid criteria to distinguish between these particular orders of insect cells. These studies were supported by Grant CA-04953-12 from the National Cancer Institute; General Research Support Grant FR-5582 from the National Institutes of Health; and Grant-in-Aid Contract M-43 from the State of New Jersey. Recipient of Research Career Award 5-K3-16,749 from the National Institutes of Health.  相似文献   
79.
C Bolotin  S Morris  B Tack  J Prahl 《Biochemistry》1977,16(9):2008-2015
The fourth component of human complement (C4) has been purified in 20% yield from fresh plasma using as starting material the 5-12% poly(ethylene glycol) precipitate which had been depleted of plasminogen by an affinity adsorbent. Sequential ion-exchange chromatography on diethylaminoethylcellulose, QAE-Sephadex, and DEAE-Bio-Gel A resulted in C4 homogeneous by immunological criteria and by polyacrylamide gel electrophoresis, the last chromatographic step achieving separation of native from inactivated C4. Reduction with 20 mM dithiothreitol for 2 h at 37 degrees C in 0.25 M 2-amino-2-hydroxymethyl-1,3-propanediol hydrochloride, pH 8.6, effected cleavage of the interchain disulfide bonds. A three-chain structure for C4 was confirmed, and molecular weight estimates of 93 000 +/- 9300, 75 000 +/- 7500, and 30 000 +/- 3000 determined for the alpha, beta, and gamma chains, respectively. The effects of known inactivators of C4 upon the chains of C4 were investigated, confirming that the inactivations by C1s and trypsin were accompanied by the fragmentation of the alpha chain. Inactivation of C4 by hydrazine, on the other hand, produced no detectable change in chain size. Separation of the chains was accomplished by gel filtration in the presence of 1 M acetic acid. Amino acid compositions of native C4 and the constitutive chains have been performed, and N-terminal sequences of the latter established by automated Edman degradation.  相似文献   
80.
The contamination of soils by trace metals has been an unfortunate sideeffect of industrialization. Some of these contaminants can interfere with vulnerable enduses of soil, such as agriculture or nature, already at relatively low levels of contamination. Reversely, conventional civil–technical soil-remediation techniques are too expensive to remediate extended areas of moderately contaminated soil. Phytoextraction has been proposed as a more economic complementary approach to deal with this specific niche of soil contamination. However, phytoextraction has been shown to be a slow-working process due to the low amounts of metals that can be annually removed from the soil under normal agronomic conditions. Therefore, extensive research has been conducted on process optimization by means of chemically improving plant availability and the uptake of heavy metals. A wide range of potential amendments has been proposed in the literature, with considerable attention being spent on aminopolycarboxylic acids such as ethylenediaminetetraacetic acid (EDTA). However, these compounds have received increasing criticism due to their environmental persistence and associated risks for leaching. This review presents an overview of potential soil amendments that can be employed for enhancing metal uptake by phytoextraction crops, with a distinct focus on more degradable alternatives to persistent compounds such as EDTA.  相似文献   
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