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21.
Rachel Baltz Jean-Luc Evrard Val/'erie Bourdon Andr/'e Steinmetz 《Sexual plant reproduction》1996,9(5):264-268
The protein PLIM-1 (formerly SF3) from sunflower is expressed exclusively in mature, free pollen. It contains two LIM domains associated with an acidic C-terminus comprising six copies of the pentapeptide motif (A,T,S) (E,D) TQN. We have expressed the pollen protein as well as some of its mutant forms inEscherichia coli and have used the bacterially produced proteins to study interactions with nucleic acids. Our studies show that the protein binds DNA and RNA in vitro to form large complexes, while mutant polypeptides containing either a single LIM domain or a destabilized first or second LIM domain do not. Although these data suggest that the biological function of PLIM-1 involves interactions with nucleic acids, its role in pollen development remains unclear. 相似文献
22.
Peter J. Robinson Michael Steinmetz Kazuo Moriwaki Kirsten Fischer Lindahl 《Immunogenetics》1984,20(6):655-665
To determine the distribution of beta-2 microglobulin (B2m) alleles in wild mice we have typed mice derived from natural populations in Europe, North Africa, South America, and East Asia. Mus musculus domesticus mice from Germany, France, Italy, and Peru were all B2m
a
as were most from the United Kingdom. M.m. musculus mice from Denmark and Czechoslovakia, several stocks of M.m. molossinus from Japan, and M.m. castaneus from China, Thailand, and the Philippines were of B2m
b
type. This is consistent with the notion that C57BL/6 may have obtained some of its genes, including B2m, from Eastern mice. A BgII restriction site characteristic of B2m
b
was also found in mice from Czechoslovakia and Japan, confirming that B2m
b
is a naturally occurring allele of B2m. A new type of
2m (
2mw1) was found in four stocks of M. spretus from Portugal, Spain, and Morocco. This molecule differs in apparent size and charge from the a and b types.
2mw2 was found together with
2 ma in one stock of M.m. domesticus (brevirostris) from Morocco.
2mw3 and
2mw4 were found in a few M. m. bactrianus from Pakistan. In all cases tested, these new
2m molecules associate with class I histocompatibility antigens.Abbreviations used in this paper
2m
beta-2 microglobulin
-
B2m
gene for beta-2 microglobulin
- IEF
isoelectric focusing
- SDS-PAGE
polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate
- MHC
major histocompatibility complex
- T. E.
Tris-EDTA buffer 相似文献
23.
Apolipoprotein A-IGiessen (Pro143----Arg). A mutant that is defective in activating lecithin:cholesterol acyltransferase 总被引:2,自引:0,他引:2
G Utermann J Haas A Steinmetz R Paetzold S C Rall K H Weisgraber R W Mahley 《European journal of biochemistry》1984,144(2):325-331
Apolipoprotein A-IGiessen is a variant form of apo A-I that is displaced from the corresponding normal A-I isoforms on isoelectric focusing gels by a single charge unit towards the cathode [Utermann et al. (1982) J. Biol. Chem. 257, 501-507]. Three subjects heterozygous for the variant were detected in one family. The percentage of the total A-I in plasma represented by the A-IGiessen in these subjects ranged over 25-30%. The variant and normal major A-I isoforms from the proband (Y.J.) were purified by preparative isoelectric focusing and cleaved with CNBr. Analytical focusing of CNBr fragments demonstrated a charge difference between CB3Giessen and normal CB3. Sequence analysis of CB3Giessen revealed that a proline existing in normal A-I was replaced by an arginine in the variant A-I at residue 143. The ability of the mutant A-I to activate purified lecithin:cholesterol acyltransferase was determined in vitro. The cofactor activity of [Arg143]apolipoprotein A-I was about 60-70% of that demonstrated by control A-I. Residue 143 is in a putative beta-turn between two of the repeating amphiphilic helices in apolipoprotein A-I and may be a critical determinant of the protein's structure and function. 相似文献
24.
Summary The antitumor and antimetastatic activities of the water-soluble peptidoglycan monomer GlnNAc-Mur-NAc-L-Ala-D-iso-Gln-meso-diamminopimelic acid (-NH2)-D-Ala-D-Ala (PGM), which has immunostimulant effects, have been evaluated in CBA mice bearing MCa mammary carcinoma. The antineoplastic effects of PGM depend strictly on the dosage and treatment schedule used. Though a significant inhibition of the primary tumor growth is observed over a wide range of dosage, only the IV administration of daily doses of 50 mg/kg/day on days 1, 5, 10, 15 inhibits spontaneous lung metastasis formation and in parallel prolongs the survival time of the treated mice. The magnitude of the antimetastatic effects of PGM depends on the degree of dissemination of the tumor, and is greater when the number of metastatic foci is low. Examination of the therapeutic potential of PGM in combination with surgery has further indicated that the timing of administration plays an important role in the overall effectiveness of this substance. A 5-day interval is necessary between two consecutive injections for the induction of significant increases of the survival times. 相似文献
25.
R A Dedonder J A Lepesant J Lepesant-Kejzlarová A Billault M Steinmetz F Kunst 《Applied and environmental microbiology》1977,33(4):989-993
A set of nine reference strains bringing convenient markers in the genetic background of Bacillus subtilis Marburg 168 has been prepared to allow rapid mapping of new markers. 相似文献
26.
J M Bard L Candelier G Agnani V Clavey G Torpier A Steinmetz J C Fruchart 《Biochimica et biophysica acta》1991,1082(2):170-176
A sequential immunoaffinity chromatography procedure was developed to isolate from whole normolipidemic human plasma a subpopulation of apoB containing particles (Lp-B) which is virtually free of non apoB protein. The absence of non apoB protein in Lp-B was assessed by enzyme immunoassay against apolipoproteins A-I, A-II, A-IV, E, C-III and (a). Electron microscopy and fractionation of the isolated particles by gel filtration demonstrated that these particles were heterogeneous in size. However, most of them had diameters between 18 and 26 nm. These particles were found to be rich in cholesterol (molar ratio cholesterol/apoB = 2246 +/- 995) poor in triacylglycerol (molar ratio triacylglycerol/apoB = 555 +/- 518) and had a phospholipids/apoB molar ratio of 713 +/- 348. Most of the cholesterol was esterified (66% +/- 5%). Lp-B particles bound to the apoB, E receptor of HeLa cells with a lower affinity than LDL prepared by ultracentrifugation (1.030 kg/l less than d less than 1.053 kg/l). (KD = 18.9 vs 10.5 nmol/l). 相似文献
27.
Genetic control of human apolipoprotein E polymorphism: Comparison of one-and two-dimensional techniques of isoprotein analysis 总被引:16,自引:0,他引:16
Summary Genetic polymorphism of human apolipoprotein E (apo E) has previously been demonstrated by one-dimensional isoelectric focusing (Utermann et al. 1977b) and by two-dimensional electrophoresis of apolipoproteins (Zannis et al. 1981), but the relationship between the results obtained by these methods remained unclear. We therefore performed comparative phenotyping by one-dimensional and two-dimensional electrophoresis. Apoproteins from very low-density lipoproteins (apo VLDL) prepared by ultracentrifugation or from an apo Erich lipoprotein fraction prepared by heparin/Mg++ precipitation, were used as a source of apo E. Six common phenotypes designated apo E-4/4, apo E-N/N, apo E-D/D, apo E-4/N, apo E-4/D, and apo E-N/D were differentiated irrespective of the technique used or the source of apolipoproteins, but the two-dimensional electrophoresis of apo VLDL and apo VLDL which had been treated with neuraminidase was the key for the correct genetic interpretation of those phenotypes exhibiting the E4 isoform of the protein. Each phenotype is characterized by the presence of either one or two of three major isoforms E2, E3, and E4 and by the presence of several minor sialylated forms of these proteins (apo Es) that have higher apparent molecular weights. The unsialylated major isoform apo E2 does not only differ in charge but also has a higher apparent mol.wt. (about 34,500) than the major isoforms apo E3 and apo E4 (mol. wt. about 33,000). Family studies including 90 matings with a total of 203 offspring confirmed the genetic one locus model of Zannis et al. (1981). Apo E phenotypes are controlled by three autosomal codominant alleles apo Ed, apo En, and apo E4 that specify for the E2, E3, and E4 isoforms respectively. Phenotypes apo E-D/D,-N/N, and-4/4 represent homozygotes and phenotypes apo E-4/N,-4/D, and-N/D heterozygotes for these alleles.The frequencies of apo E alleles in 1031 blood donors were apo E4=0.150, apo En=0.773, and apo Ed=0.077. Homozygosity for the allele apo Ed is associated with hyperlipoproteinemia type III. Hence a large number of the population (about 1%) are at risk for this specific lipoprotein disorder that is associated with premature atherosclerosis and xanthomatosis. 相似文献
28.
Cloning of V region fragments from mouse liver DNA and localization of repetitive DNA sequences in the vicinity of immunoglobulin gene segments. 总被引:12,自引:4,他引:8 下载免费PDF全文
Two different kappa light chain genes have previously been isolated from one mouse myeloma. The V (variable, abbreviations in ref. 2) gene segments of the two genes were now used to identify their germline counterparts in EcoRI digests of mouse liver DNA. In addition two sets of related V gene segments were found which hybridize with either of the two DNA probes. Five of the V region fragments of one set were cloned in a lambda phage vector and partially characterized by restriction mapping and Southern blot hybridization. Repetitive DNA sequences were found on each of the five fragments as well as on other cloned immunoglobulin gene containing fragments. Cross-hybridization between some but not all of the regions containing repetitive DNA sequences was observed. 相似文献
29.
Vittorio Baroncelli Gianfranco Boccalon Ivo Giannini Pierluigi Renzi 《Molecular and cellular biochemistry》1979,28(1-3):3-6
Summary In this work the terminal oxidase system of C. lipolytica grown on n-alkanes was identified, and partially purified. Spectral characteristics typical of cytochrome O are obtained, inhibition and photodissociation of CO are reported. 相似文献
30.
Jan Klein Christophe Benoist Chella S. David Peter Demant Kirsten Fischer Lindahl Lorraine Flaherty Richard A. Flavell Ulrich Hämmerling Leroy E. Hood Stephen W. Hunt III Patricia P. Jones Philippe Kourilsky Hugh O. McDevitt Daniel Meruelo Donal B. Murphy Stanley G. Nathenson David H. Sachs Michael Steinmetz Susumu Tonegawa Edward K. Wakeland Elizabeth H. Weiss 《Immunogenetics》1990,32(3):147-149