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941.
Cloning and sequencing of PYBP, a pyrimidine-rich specific single strand DNA-binding protein. 总被引:17,自引:10,他引:7
In the human transferrin gene promoter, PRI and DRI are positive cis-acting elements interacting respectively with two families of proteins, Tf-LF1 and Tf-LF2. In this paper, we report the purification from rat liver nuclei, of one of these factors, PYBP, as well as the cloning and the sequencing of its cDNA. PYBP is a DNA-binding protein, purified as a 58 kDa doublet which binds only to single strand pyrimidine-rich DNA present for example in PRI and DRI. The protein binds also to a similar polypyrimidine tract present in one of the two strands of a DNA regulatory element of the rat tyrosine aminotransferase gene enhancer. PYBP gene is transcribed ubiquitously as a roughly 2.8 kb RNA which is likely to be subject to an alternative splicing. PYBP is highly homologous to a mouse nuclear protein, as well as to PTB, its human version, which interacts specifically with the pyrimidine tracts of introns. Primary structure information and predicted secondary structure elements of the protein indicate that PYBP contains four sequence repeats. Each of these repeats appears to exhibit the typical RNA recognition motif found in several proteins interacting with RNA or single strand DNA. Finally several hypotheses concerning the biological function of PYBP are presented. 相似文献
942.
943.
Marcello Zambito Teresa Ferrara Cinzia Termini Salvatore Corrao Girolamo Passalacqua Antonino Salvia 《Aerobiologia》1992,8(3):341-344
Summary Epidemiological and aerobiological observations (1987;1989) have been carried out for three years in order to search the existing relationship between the Gramineae's daily pollen concentration in Palermo's atmosphere and the number of hay fever cases due to such pollen.The aerobiological data were obtained with a 2000 VPPS volumetric sampler. Clinical research was performed on 555 hay fever patients treated in our ambulatory over a three-year period (1987–1989).These data, elaborated by a seven day running mean method and correlated with epidemiological data, evidenced that three of the pollen families in our territory are clinically important: Urticaceae,Parietaria prevailing among them, Gramineae and Oleaceae,Olea europaea prevailing among them.The Gramineae are the second most important allergenic pollen (32,08% of all the pollinosis) whereas, as far as its concentration in the atmosphere is concerned; it ranks third followingParietaria and Oleaceae. 相似文献
944.
Biochemical analysis of a novel H-2 class I-like glycoprotein expressed in five AKR-(Gross virus) derived spontaneous T cell leukemias 总被引:1,自引:0,他引:1
M O Labeta N Fernandez A Reyes P Ferrara O Marelli E Le Roy J Houlihan H Festenstein 《Journal of immunology (Baltimore, Md. : 1950)》1989,143(4):1245-1253
The H-2 class I Ag profiles of five spontaneous AKR (H-2K) Gross virus leukemic cell lines were analyzed. A novel H-2 class I, "alloantigen"-like glycoprotein was immunoprecipitated and isolated from all the tumor cell lines using an H-2Dd-specific mAb 35-5-8. The novel Ag was also recognized in vitro by anti-H-2Dd-specific CTL. In addition, DNA from all the thymomas, but not the DNA from normal adult AKR thymic cells showed a transcribed gene detectable with an H-2Dd-specific oligonucleotide probe. The molecular profile of the novel antigen was further studied by two-dimensional gel electrophoresis and analyzed by a computer based image analyzer system and reverse-phase HPLC tryptic peptide mapping. Its molecular pattern was different from the syngeneic H-2Kk, H-2Dk, and the allogeneic H-2Dd gene products. The two-dimensional gel pattern of the novel H-2 class I molecule had a different overall structure reflected in isoelectric point, number, and distribution of polypeptide spots. The tryptic peptide map analysis showed six peaks exclusively identified with the novel Ag. The calculated degree of homology with the corresponding H-2Dd, H-Dk, and H-Kk peptides was 41, 56, and 51%, respectively. In addition, an unusual cell surface distribution of the novel Ag was observed in most of the leukemic lines. The removal of sialic acid residues by neuraminidase treatment facilitated the detection of the allodeterminants by anti-H-2Dd-specific mAb and CTL. Furthermore, we showed that in one AKR tumor line, 424, there is a close association of the novel Ag with the syngeneic class I molecules. Prior preclearance of the syngeneic class I molecules revealed the presence of the H-2Dd-like allospecificity. The genetic and molecular relationship between the expression of this novel class I-like glycoprotein and the recently sequenced Q5 gene is under current investigation. 相似文献
945.
A method of energy minimization for conformational energy calculations using the least-squares technique has been reported. The method has been tested in the simple case of a pair of alanyl peptide units using the non-bonded potential energy. Starting from any point in the (φ, ψ) energy map (not necessarily near a minimum), convergence to one of the energy minima is achieved rapidly, within a few cycles of iteration. 相似文献
946.
G B Ferrara A J Strelkauskas A Longo J McDowell E J Yunis S F Schlossman 《Journal of immunology (Baltimore, Md. : 1950)》1979,123(3):1272-1277
Analysis by the indirect fluorescence test followed by fluorescence-activated cell sorter (FACS) analysis has shown that antisera recognizing subsets of human T lymphocytes can be produced by planned immunizations involving HLA-A and HLA-B compatible donors. The reactivity of these antisera against some individuals of a population but not others shows that they recognize a polymorphic cell surface component. The reactive subpopulation largely overlaps with the JRA+ subset, which was previously shown to possess regulatory properties in functional assays. The specificity of the antisera for a T cell subset and the unrelatedness of the anti-B cell activity of the same antisera has been confirmed by two-color fluorescence tests. 相似文献
947.
J. de Pascual Teresa A.F. Barrero L. Muriel A. San Feliciano M. Grande 《Phytochemistry》1980,19(6):1153-1156
Three new diterpene acids have been isolated from the leaves of Juniperus communis and their structures, elucidated by spectroscopic methods, were identified as 7-oxo-13-epi- pimara-8,15-dien-18-oic acid, 7α-hydroxysandaracopimaric acid and (14 S)-14,15-dihydroxylabda- 8(17),13(16)-dien-19-oic acid. Biflavonyls, fatty acids and diterpenoids with known structures were also isolated. 相似文献
948.
beta-endorphin: synthesis of analogs with extension at the carboxyl terminus with high radioreceptor binding activity 总被引:3,自引:0,他引:3
D Yamashiro P Ferrara C H Li 《International journal of peptide and protein research》1980,16(1):70-74
Four analogs of human beta-endorphin (beta h-EP) have been synthesized: [Gly31]-Beta h-EP-Gly-NH2, [CH3(CH2)4NH231]-beta h-EP, [Gly31]-beta h-EP-Gly-Gly-NH2, and [Gln8, Gly31]-betah-EP-Gly-Gly-NH2. All are more active than beta h-EP in an opiate receptor binding assay. Stepwise extension at the COOH-terminus shows a progressive increase in binding activity. The last analog, which combines extension at the COOH-terminus with elimination of the remaining anionic charge in beta h-EP, is nine times more active than the parent molecule. 相似文献
949.
950.