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1.
Extraction of Carnegiea gigantea yielded a new 3,4-dihydroisoquinoline alkaloid, dehydroheliamine; the structure was confirmed by synthesis. 相似文献
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Tracey C. Bourner Enrique Vargas‐Osuna Trevor Williams Candido Santiago‐Alvarez Jenny S. Cory 《Biocontrol Science and Technology》1992,2(4):315-326
Agrotis segetum nuclear polyhedrosis virus (AsNPV) and granulosis virus (AsGV), propagated in laboratory cultures of A. segetum in England and A. ipsilon in Spain, respectively, were applied to plots of maize plants at the one‐ to four‐leaf stage of growth. Plots were arranged in a 6 x 6 Latin square design and infested with second‐instar A. segetum larvae (the common cutworm). Each virus was applied in separate treatments by two application methods; as an aqueous spray containing 0.1% Agral as a wetting agent, and as a bran bait. The NPV was applied at a rate of 4 X 1012 polyhedra/ha, and the GV at 4 X 1013 granules/ha. Soil and plants were sampled for larvae on three occasions following virus treatment: 24 h, 4 days and 11 days. The larvae were reared on diet in the laboratory, until death or pupation, to examine the rate and level of viral infection. Infection data showed 87.5% and 91% NPV infection and 12.5% and 55% GV infection in spray and bait treatments, respectively, in larvae sampled 24 h after treatment. In larvae sampled 4 days after treatment, the results were 78% and 100% NPV infection, and 13% and 6% GV infection. A total of only six larvae were retrieved on day 11. In both treatments larvae infected with AsNPV died significantly more rapidly and at an earlier instar than those infected with AsGV, indicating that AsNPV appears to have better potential as a control agent for A. segetum. 相似文献
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Cloning and analysis of cDNA sequences coding for two 16 kilodalton heat shock proteins (hsps) in Caenorhabditis elegans: homology with the small hsps of Drosophila. 总被引:13,自引:0,他引:13 下载免费PDF全文
The nucleotide sequences of two different cDNAs, CEHS48 and CEHS41, coding for the 16,000 dalton heat shock proteins (hsps) of Caenorhabditis elegans have been determined. CEHS48 codes for a polypeptide of 135 amino acids, approximately 15 fewer than the complete protein while CEHS41 is missing approximately 46 amino acids. From nucleotide 113 to the TAA termination signal the extent of homology between the sequences is 91%. Toward the 5' ends, the homology drops to 20% and results in completely divergent amino acid sequences. The 3' noncoding regions are only 30% homologous. Only CEHS48 contains a poly(A) signal and a poly(A) tail, suggesting that CEHS41 has an incomplete 3' end. The region from amino acid 43 to amino acid 115 shows extensive homology with corresponding regions in the four small hsps of Drosophila melanogaster and in mammalian alpha-crystallin. Two-dimensional gel analysis of in vitro synthesized hsp16 reveals the existence of five distinct components of identical molecular weights, but with different isoelectric points. 相似文献
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Estaras Matias Ortiz-Placin Candido Castillejo-Rufo Alba Fernandez-Bermejo Miguel Blanco Gerardo Mateos Jose M. Vara Daniel Gonzalez-Cordero Pedro L. Chamizo Sandra Lopez Diego Rojas Adela Jaen Isabel de Armas Noelia Salido Gines M. Iovanna Juan L. Santofimia-Castaño Patricia Gonzalez Antonio 《Journal of physiology and biochemistry》2023,79(1):235-249
Journal of Physiology and Biochemistry - We have investigated the effects of melatonin on major pathways related with cellular proliferation and energetic metabolism in pancreatic stellate cells.... 相似文献
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A Caenorhabditis elegans lambda ZAP cDNA library was screened using a fragment amplified from highly conserved regions of the mammalian and Drosophila elongation factor 2 (EF-2). Two types of cDNA clones were obtained, corresponding to two mRNA species with 3'-untranslated regions of 60 and 115 nucleotides, both encoding identical polypeptides. Sequence analysis of these clones and comparisons with hamster and Drosophila EF-2 sequences suggests that they encode C. elegans EF-2. Clone pCef6A, encoding the entire C. elegans EF-2 mRNA sequence including 45 nucleotides of 5'-untranslated region, contains a 2,556-bp open reading frame which predicts a polypeptide of 852 amino acid residues (Mr 94,564). The deduced amino acid sequence is greater than 80% identical to that of mammalian and Drosophila EF-2. Conserved sequence segments shared among a variety of GTP-binding proteins are found in the amino-terminal region. The carboxy-terminal half contains segments unique to EF-2 and its prokaryotic homolog, EF-G, as well as the histidyl residue which is ADP-ribosylated by diphtheria toxin. The C. elegans protein contains a 12-amino-acid insertion between positions 90 and 100, and a 13-amino-acid deletion between positions 237 and 260, relative to hamster EF-2. Partial sequencing of a genomic clone encoding the entire C. elegans EF-2 gene (named eft-2) has so far revealed two introns of 48 and 44 bp following codons Gln-191 and Gln-250, respectively. Southern and Northern blot analyses indicate that eft-2 is a single-copy gene and encodes a 3-kb mRNA species which is present throughout nematode development. 相似文献
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Organization of the Rosy Locus in DROSOPHILA MELANOGASTER: Further Evidence in Support of a CIS-Acting Control Element Adjacent to the Xanthine Dehydrogenase Structural Element 下载免费PDF全文
M. McCarron J. O''Donnell A. Chovnick B. S. Bhullar J. Hewitt E. P. M. Candido 《Genetics》1979,91(2):275-293
The present report summarizes our recent progress in the genetic dissection of an elementary genetic unit in a higher organism, the rosy locus (ry:3--52.0) in Drosophila melanogaster. Pursuing the hypothesis that the rosy locus includes a noncoding control region, as well as a structural element coding for the xanthine dehydrogenase (XDH) peptide, experiments are described that characterize and map a rosy locus variant associated with much lower than normal levels of XDH activity. Experiments are described that fail to relate this phenotype to alteration in the structure of the XDH peptide, but clearly associate this character with variation in number of molecules of XDH per fly. Large-scale fine-structure recombination experiments locate the genetic basis for this variation in the number of molecules of XDH per fly to a site immediately to the left of the XDH structural element within a region previously designated as the XDH control element. Moreover, experiments clearly separate this "underproducer" variant site from a previously described "overproducer" site within the control region. Examination of enzyme activity in electrophoretic gels of appropriate heterozygous genotypes demonstrates the cis-acting nature of this variation in the number of molecules of XDH. A revision of the map of the rosy locus, structural and control elements is presented in the light of the additional mapping data now available. 相似文献