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81.
Capping of Viral RNA in Cultured Spodoptera frugiperda Cells Infected with Autographa californica Nuclear Polyhedrosis Virus 总被引:4,自引:2,他引:2
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Viral RNA from fall armyworm (Spodoptera frugiperda) cells infected with Autographa californica nuclear polyhedrosis virus contains cap structures. Most of the cap labeled in vivo with [3H]methionine or 32Pi cochromatographed on DEAE-cellulose with the −5 charge marker; a minor component appeared at −4 net charge. The former is probably a cap 1 structure (m7GpppXmpYp), and the latter is probably a cap 0 (m7GpppXp). On the basis of relative labeling of the two caps with [3H]adenosine and [3H]guanosine, we concluded that each cap contained at least one adenosine residue in addition to guanosine and, therefore, that cap 0 contained m7GpppAp. Cleavage of [3H]methionine-labeled viral RNA with tobacco acid pyrophosphatase released a labeled component that cochromatographed on polyethyleneimine-cellulose with m7Gp, confirming the m7GpppX linkage in the cap. These results were also seen with host polyadenylated RNA. The caps appeared in nearly equal abundance in viral polyadenylated and non-polyadenylated RNAs. The ratio of 32Pi incorporated into the cap to that incorporated into mononucleotides suggested average lengths for the polyadenylated and non-polyadenylated RNAs of 1,800 and 1,200 nucleotides, respectively. 相似文献
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Internuclear Genetic Transfer in Dikaryons of SCHIZOPHYLLUM COMMUNE. II. Direct Recovery and Analysis of Recombinant Nuclei
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The recessive gene, mound (mnd), allows the appearance of globose masses of compacted hyphae. Dikaryons of Schizophyllum commune that are heteroallelic for mnd [(mosaic dikaryons: (mnd + mnd(+))] have been successfully dedikaryotized in cholate-containing medium in order to recover the component nuclear types directly. The relative proportion of the two recovered monokaryotic types shows in all cases a marked deviation from 1:1. Hyphae from nonmound mycelial regions yield monokaryotic types identical to those originally used to form the dikaryons. In hyphae from mound-forming regions, however, homoallelism of the mnd allele has been demonstrated; the nuclear type that formerly contained the mnd(+) allele acquired a mnd allele.-The process of internuclear transfer or recombination is unaccompanied by the simultaneous alteration of any additional genetic markers carried by the recipient nucleus. The newly acquired mnd allele segregates in Mendelian fashion in subsequent outcrosses and appears to be chromosomally located. A novel process of somatic recombination, with several features distinct from classical parasexual mitotic recombination, appears to be in operation. 相似文献
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Rooney RF 《California State Journal of Medicine》1922,20(10):354-356
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徐丽娜及本文作者曾报告利血平对正常狗的食物唾液条件反射和血压有明显的影响,而对非条件反射的影响很小。以前作者和同事們研究小量利血平对腎型高血压狗的降压疗效时,曾观察到每天口服0.003及0.005毫克/公斤的利血平大都能使血压明显下降,其下降程度比正常狗显著。和及报告在高血压时中樞神經系統的功能状态有明显的改变。利血平对高血压狗及正常狗条 相似文献
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KAISER RF 《Public Health Reports》1951,66(24):757-761
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