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51.
Abstract A purification procedure (Z ee et al. 1987) for closterovirus-like particles associated with grapevine leafroll disease was improved after various sources of plant tissues, extraction buffers, pH values, and centrifugation techniques had been examined. An antiserum against the CA-4 isolate was produced and used in ELISA. The virus-like particles of the NY-1 isolate measured in crude plant preparations were about 1,800 to 1,900 nm long. The molecular weight of coat protein of the NY-1and NY-2 isolates were ca. 43 × 103 daltons in SDS-PAGE analysis; and bands having this molecular weight reacted in Western blotting tests with specific polyclonal and monoclonal antibodies. A large dsRNA molecule (ca. 10 × 106 Mr) along, with lower molecular weight species were isolated from leafroll diseased grapevines, but not from healthy grapevines. Seven leafroll isolates were tested for their serological relatedness in a protein A-gold labelling immunosorbent electron microscopy, assay. Results indicated that serologically distinct serotypes existed, and mixed infection of grapevines with different scrotypes was common. A grouping of isolates into serotype I, II, III, IV is proposed.  相似文献   
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Certain parameters of wound healing were investigated in mouse skin given 950 rads and 3325 rads of X-irradiation at various times relative to wounding. Increased inflammation, delayed dermal regeneration, and delayed contraction were noted in all irradiated groups. The activation of surrounding hair follicles, a process that usually accompanies wounding in mouse skin, occurred earlier, over a shorter elapsed time, and over a greater area of skin in animals irradiated prior to wounding than in the controls or in those irradiated and wounded simultaneously. Epidermal mitotic activity in wounds made at the time of irradiation was initially depressed but recovered by the second postoperative day. Wounds in pre-irradiated animals gave an unexpected result. They responded with an immediate burst of mitotic activity without the usual 24-hr lag that was seen in controls. In the pre-irradiated specimens a substantial number of cells appeared to die after dividing.  相似文献   
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Aspergillus penicillioides is a true halophile, present in diverse econiches from the hypersaline athalassohaline Dead Sea and the thalassohaline solar salterns, to the polyhaline estuaries and mangroves of Goa-India. Thirty-nine isolates from these environments were seen to be moderate halophiles, stenohaline or euryhaline in nature, with comparable salt tolerance indices. They had an obligate need for a low water activity and were unable to grow on a regular defined medium such as Czapek Dox Agar, or on various nutrient rich agar media such as Malt Extract, Potato Dextrose and Sabouraud Agar; however, growth was obtained on all these media when amended with 10 % solar salt. In the absence of added salt, the conidia either did not germinate, or when germinated, distortions and lysis were seen in the short mycelial forms; on media with salt, the mycelia and vesicles appeared normal.  相似文献   
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Summary Plum hypocotyl slices were transformed with the coat protein (CP) gene of plum pox virus (PPV-CP) following cocultivation with Agrobacterium tumefaciens containing the plasmid pGA482GG/PPVCP-33. This binary vector carries the PPV-CP gene construct, as well as the chimeric neomycin phosphotransferase and -glucuronidase genes. Integration and expression of the transferred genes into regenerated plum plants was verified through kan resistance, GUS assays, and PCR amplification of the PPV-CP gene. Twenty-two transgenic clones were identified from approximately 1800 hypocotyl slices. DNA, mRNA, and protein analyses of five transgenic plants confirmed the integration of the engineered CP gene, the accumulation of CP mRNA and of PPV-CP-immunoreactive protein. CP mRNA levels ranged from high to undetectable levels, apparently correlated with gene structure, as indicated by DNA blot analysis. Western analysis showed that transgenic plants produced amounts of CP which generally correlated with amounts of detected mRNA.  相似文献   
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Screening promoters for Anthurium transformation using transient expression   总被引:1,自引:0,他引:1  

Key message

There are multiple publications on Anthurium transformation, yet a commercial product has not been achieved. This may be due to use of non-optimum promoters here we address this problem.

Abstract

Different promoters and tissue types were evaluated for transient β-glucuronidase (GUS) expression in Anthurium andraeanum Hort. ‘Marian Seefurth’ following microprojectile bombardment. Plasmids containing the Ubiquitin 2, Actin 1, Cytochrome C1 from rice, Ubiquitin 1 from maize and 35S promoter from Cauliflower Mosaic Virus fused to a GUS reporter gene were bombarded into in vitro grown anthurium lamina, somatic embryos and roots. The number of GUS foci and the intensity of GUS expression were evaluated for each construct. Ubiquitin promoters from rice and maize resulted in the highest number of expressing cells in all tissues examined. Due to the slow growth of anthurium plants, development of transgenic anthurium plants takes years. This research has rapidly identified multiple promoters that express in various anthurium tissues facilitating the development of transformation vectors for the expression of desirable traits in anthurium plants.  相似文献   
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