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31.
Improving foreign protein accumulation is crucial for enhancing the commercial success of plant-based production systems since product yields have a major influence on process economics. Cereal grain evolved to store large amounts of proteins in tightly organized aggregates. In maize, γ-Zein is the major storage protein synthesized by the rough endoplasmic reticulum (ER) and stored in specialized organelles called protein bodies (PB). Zera® (γ-Zein ER-accumulating domain) is the N-terminal proline-rich domain of γ-zein that is sufficient to induce the assembly of PB formation. Fusion of the Zera® domain to proteins of interest results in assembly of dense PB-like, ER-derived organelles, containing high concentration of recombinant protein. Our main goal was to increase recombinant protein accumulation in plants in order to enhance the efficiency of orally-delivered plant-made vaccines. It is well known that oral vaccination requires substantially higher doses than parental formulations. As a part of a project to develop a plant-made plague vaccine, we expressed our model antigen, the Yersinia pestis F1-V antigen fusion protein, with and without a fused Zera® domain. We demonstrated that Zera®-F1-V protein accumulation was at least 3× higher than F1-V alone when expressed in three different host plant systems: Ncotiana benthamiana, Medicago sativa (alfalfa) and Nicotiana tabacum NT1 cells. We confirmed the feasibility of using Zera® technology to induce protein body formation in non-seed tissues. Zera® expression and accumulation did not affect plant development and growth. These results confirmed the potential exploitation of Zera® technology to substantially increase the accumulation of value-added proteins in plants.  相似文献   
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33.
Composition of the urogenital system, oocyte development, gamete morphology, and features of embryonic development are described in Scorpaenopsis possi and Sebastapistes cyanostigma (Scorpaenidae) from the Nha Trang Bay, the South China Sea (Vietnam). In males of both species, paired spermiducts enter into the anterior dorsal part of the hypertrophied urinary bladder containing mature sperm. The duration of progressive movements of spermatozoa obtained from the testes and urinary bladder is 5–6 and 12–15 min after activation, respectively. Ovulated oocytes possess oval shapes, they are transparent and without oil droplets. The oocytes are embedded into the floating gelatinous matrix. Insemination of the eggs in nature is apparently external. The embryos of S. cyanostigma hatch at a more advanced morphological condition in comparison to the embryos of Sc. possi. The features of reproductive biology are discussed in the context of the evolution of viviparity within the family.  相似文献   
34.
The human gamma-herpesviruses, EBV and Kaposi's sarcoma-associated herpesvirus, are widely disseminated and are associated with the onset of a variety of malignancies. Thus, the development of prophylactic and therapeutic vaccination strategies is an important goal. The experimental mouse gamma-herpesvirus, gammaHV68 (or MHV-68), has provided an in vivo model for studying immune control of these persistent viruses. In the current studies, we have examined infectivity, immunogenicity, and protective efficacy following infection with a replication-deficient gammaHV68 blocked in late viral gene expression, ORF31STOP. The data show that ORF31STOP was able to latently infect B cells. However, the anatomical site and persistence of the infection depended on the route of inoculation, implicating a role for viral replication in viral spread but not the infectivity per se. Furthermore, i.p. infection with ORF31STOP elicited strong cellular immunity but a non-neutralizing Ab response. In contrast, intranasal infection was poorly immunogenic. Consistent with this, mice infected i.p. had enhanced control of both the lytic and latent viral loads following challenge with wild-type gammaHV68, whereas intranasal infected mice were not protected. These data provide important insight into mechanisms of infection and protective immunity for the gamma-herpesviruses and demonstrate the utility of replication-deficient mutant viruses in direct testing of "proof of principal" vaccination strategies.  相似文献   
35.
Basbag S  Ekinci R  Gencer O 《Hereditas》2007,144(5):185-190
The objective of this study was to estimate the general combining ability of the parents and specific combining ability of hybrids for earliness traits for line selection. Inheritance and interrelationships of earliness characters were evaluated in a line x tester design. Three intermediate-early-maturing female (lines) which are grown regionally and four early-maturing males (testers) cotton varieties were crossed in 2003. The twelve F(1) and seven parents were planted randomized block design with three replications in 2004. For each earliness trait, general combining ability (GCA) and specific combining ability and gene effects were estimated using the line x tester method of analysis and also were determined heterosis and narrow sense heritability. Parents and their hybrids (except the monopodial branch) were significant for all the earliness traits studied. Estimates of variance due to GCA and SCA and their ratio revealed predominantly non-additive gene effects for date of first square, date of first flowers and harvested rate of first picking. Among the lines, Ersan 92 and Maras 92 and among the testers Acala Royal was found to be the best general combiners for most of the earliness characters. Four out of twelve crosses namely Ersan 92 x Chirpan 603, Ersan 92 x Acala Maxa, Maras 92 x Acala Royal and Nazilli 87 x Acala Royal were found to be the best crosses for investigated earliness characters.  相似文献   
36.
The species composition and relative abundance of predatory arthropod fauna were studied in organic strawberry fields in northwestern Turkey using sweep net sampling and pitfall trapping (activity density). Arachnida constituted 13.1 and 11.5% of the sweep net and pitfall trap catches, respectively. Among the predatory insects, the most abundant groups were Heteroptera (26.7%), Diptera (25.9%), Coleoptera (16.9%) and Orthoptera (10.8%) in sweep net samples. Coleoptera (84.2%) dominated the pitfall trap catches. Many aphid specific and polyphagous predators reached peak abundance during June and July. Pearson's two-tailed correlations showed a significant and positive relationship between syrphid, coccinellid or chrysopid predator numbers and strawberry aphid density. Aphid density was not significantly correlated with carabid or with nabid abundance. Examination of spatial distribution patterns of all predatory arthropod groups using Taylor's Power Law indicated that most arthropod predators, except carabids, exhibited aggregated dispersion patterns. Coccinellids changed their spatial patterns from a uniform to an aggregated distribution through the season. There was also a significant linear correlation between Anterastes sp. abundance (larvae+adults) and Isophya rectipennis+Poecilimon ricteri (larvae+adults) density at both locations. We observed, for the first time, Anterastes preying on Isophya and Poecilimon species. The seasonal abundance of the major predatory groups were described, and their potential importance in controlling strawberry aphid and other pests is discussed.  相似文献   
37.
In this study we assessed the effectiveness of fluid viscosities placed in the peritoneal cavity to prevent postoperative peritoneal adhesions. Thirty-six Wistar albino female rats (average weight: 160 +/- 30 g, average age: 6.5 months) were divided into three groups of equal number. A standard adhesion pattern was formed in each group. Then, 3 ml isotonic sodium chloride solution (relative viscosity value: 1) was added into the peritoneal cavity of group 1; 3 ml standard 6% hydroxy ethyl starch solution (HES) (relative viscosity value: 2.9) was added into the peritoneal cavity of group 2; and a standard HES solution that was concentrated by dehydration (relative viscosity value: 249.7) was added into the peritoneal cavity of group 3. All rats were sacrificed on postoperative day 10 and the adhesions that formed were graded. In group 1, grade-3 adhesions developed in 9 (75%) rats, and grade-2 developed in 3 (25%) rats. In group 2, grade-3 adhesions developed in 1 (8.3%) rat, grade-2 developed in 6 (50%) rats, and grade-1 developed in 5 (41.6%) rats; in group 3, grade-3 adhesions developed in 9 (75%) rats, and grade-2 developed in 3 (25%) rats. The adhesion scores of group 3 and group 1 were equal to each other (P=1), while the adhesion score of group 2 was significantly less (chi(2): 18.23, P<0.001). Increasing the viscosity of fluids that are inserted in the peritoneal cavity may reduce the formation of postoperative peritoneal adhesions till a critical value of unknown viscosity is achieved. The mechanism behind this process remains unclear.  相似文献   
38.
Mukhopadhyay P  Basak S  Ghosh TC 《Gene》2007,400(1-2):71-81
Synonymous codon usage and cellular tRNA abundance are thought to be co-evolved in optimizing translational efficiencies in highly expressed genes. Here in this communication by taking the advantage of publicly available gene expression data of rice and Arabidopsis we demonstrated that tRNA gene copy number is not the only driving force favoring translational selection in all highly expressed genes of rice. We found that forces favoring translational selection differ between GC-rich and GC-poor classes of genes. Supporting our results we also showed that, in highly expressed genes of GC-poor class there is a perfect correspondence between majority of preferred codons and tRNA gene copy number that confers translational efficiencies to this group of genes. However, tRNA gene copy number is not fully consistent with models of translational selection in GC-rich group of genes, where constraints on mRNA secondary structure play a role to optimize codon usage in highly expressed genes.  相似文献   
39.
We determined the effects of immobilization stress on antioxidant status, protein oxidation and lipid peroxidation in brain, liver, kidney, heart and stomach of rats. Sixteen male Wistar rats (3 months old) were divided into controls (C) and immobilization stress group (IS). IS rats were immobilized for 180 min/day for 15 days. Plasma corticosterone levels were increased in IS group. Copper,zinc-superoxide dismutase activities were increased in brain, liver and kidney, but decreased in the heart and stomach after immobilization. Catalase activities were increased in brain, kidney and heart, and decreased in liver and stomach. Selenium-dependent glutathione peroxidase activities were decreased in brain and kidney, but increased in heart and stomach. Reduced glutathione levels were decreased, while protein carbonyl, conjugated dienes and thiobarbituric acid-reactive substances levels were increased in all tissues. Our results showed that the response of antioxidant defense system to stress differs for each tissue, and protein oxidation and lipid peroxidation is induced by immobilization stress in peripheral tissues.  相似文献   
40.
Hritcu  Lucian  Bagci  Eyup  Aydin  Emel  Mihasan  Marius 《Neurochemical research》2015,40(9):1799-1809
Neurochemical Research - Ferulago angulata (Apiaceae) is a shrub indigenous to western Iran, Turkey and Iraq. In traditional medicine, F. angulata is recommended for treating digestive pains,...  相似文献   
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