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101.
QTL analysis of leaf morphology in tetraploid Gossypium (cotton) 总被引:13,自引:0,他引:13
C. Jiang R. J. Wright S. S. Woo T. A. DelMonte A. H. Paterson 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2000,100(3-4):409-418
Molecular markers were used to map and characterize quantitative trait loci (QTLs) determining cotton leaf morphology and
other traits, in 180 F2 plants from an interspecific cross between a Gossypium hirsutum genotype carrying four morphological mutants, and a wild-type Gossypium barbadense. The prominent effects of a single region of chromosome 15, presumably the classical ”Okra-leaf” locus, were modified by
QTLs on several other chromosomes affecting leaf size and shape. For most traits, each parent contained some alleles with
positive effects and others with negative effects, suggesting a large potential for adapting leaf size and shape to the needs
of particular production regimes. Twenty one QTLs/loci were found for the morphological traits at LOD≥3.0 and P≤0.001, among which 14 (63.6%) mapped to D-subgenome chromosomes. Forty one more possible QTLs/loci were suggested with 2.0≤LOD<3.0
and 0.001<P≤0.01. Among all of the 62 possible QTLs (found at LOD≥2.0 and P≤0.01) for the 14 morphological traits in this study, 38 (61.3%) mapped to D-subgenome chromosomes. This reinforces the findings
of several other studies in suggesting that the D-subgenome of tetraploid cotton has been subject to a relatively greater
rate of evolution than the A-subgenome, subsequent to polyploid formation.
Received: 26 April 1999 / Accepted: 30 July 1999 相似文献
102.
103.
Jeong BY Jeong WG Moon SK Ohshima T 《Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology》2002,131(2):251-259
The effect of dietary lipid on the fatty acid composition of muscle, testis and ovary of cultured sweet smelt, Plecoglossus altivelis, was investigated and compared with that of wild sweet smelt. Cultured fish were fed three different diets for 12 weeks: a control diet rich in docosahexaenoic acid (DHA, 22:6n-3) and eicosapentaenoic acid (EPA, 20:5n-3) (CO group); a diet deficient in DHA and EPA (DP group); and a diet rich in alpha-linolenic acid (ALA, 18:3n-3), but deficient in DHA and EPA (LP group). The fatty acid composition of muscle and gonad lipids was related with dietary fatty acids. Despite the difference in DHA and EPA content in the diets, muscles and gonads, respectively, contained almost equal levels of DHA and EPA in each CO and DP group. However, the muscle and gonad of the LP group showed a lower level of DHA than other groups, due to having the highest level of ALA. In the wild fish muscle, the DHA content was similar to that of CO and DP groups, but the EPA content showed the highest level in all groups. There was no difference in the muscle fatty acid proportions between male and female. On the other hand, the testes of cultured and wild fish were rich in DHA, EPA, docosapentaenoic acid and arachidonic acid, while ovaries were rich in oleic, palmitoleic, linoleic acids and ALA. Moreover, of all the groups, the fish fatty acid composition of the LP group was closest to that of wild fish. These results indicate that in the sweet smelt, tissue n-3 polyunsaturated fatty acids (PUFAs) greater than C20 can be synthesized from dietary precursors and special fatty acids are preferentially accumulated to the testis or ovary, respectively, to play different physiological functions. 相似文献
104.
The silencing of specific oncogenes via RNA interference (RNAi) holds great promise for the future of cancer therapy. RNAi
is commonly carried out using small interfering RNA (siRNA) composed of a 19 bp duplex region with a 2-nucleotide overhang
at each 3′ end. This classical siRNA structure, however, can trigger non-specific effects, which has hampered the development
of specific and safe RNAi therapeutics. Previously, we developed a novel siRNA structure, called asymmetric shorter-duplex
siRNA (asiRNA), which did not cause the non-specific effects triggered by conventional siRNA, such as off-target gene silencing
mediated by the sense strand. In this study, we first screened potent asiRNA molecules targeting the human c-MET gene, a promising
anticancer target. Next, the activity of a selected asiRNA was further optimized by introducing a locked nucleic acid (LNA)
to maximize the gene silencing potency. The optimized asiRNA targeted to c-MET may have potential as a specific and safe anticancer
RNAi therapeutic. 相似文献
105.
Nam Jin Noh Yowhan Son Jin Woo Koo Kyung Won Seo Rae Hyun Kim Yoon Young Lee Kyung Seun Yoo 《Journal of Plant Biology》2010,53(1):61-69
The nitrogenase activity, root nodule biomass, and rates of nitrogen (N) fixation were measured in 25-year-old pure north-
and south-facing Robinia pseudoacacia stands in an urban forest of Seoul (Kkachisan Mountain) in central Korea. The nitrogenase activity was estimated using an
acetylene reduction (AR) assay, which showed an increasing trend during the early growing season, with sustained high rates
from June through to September with a decrease thereafter. July had the highest nitrogenase activity rate (micromoles C2H4 per gram dry nodule per hour), averaging 95.8 and 115.1 for the north- and south-facing stands, respectively. The maximum
root nodule biomass (kilograms per hectare) was 45.7 and 9.1 for the north- and south-facing stands in July, respectively.
The AR rate appeared to be strongly correlated to the soil temperature (r
2 = 0.68, P < 0.001) and soil pH (r
2 = 0.59, P < 0.001) while root nodule biomass was correlated to the soil temperature (r
2 = 0.36, P < 0.01) and water content (r
2 = 0.35, P < 0.05). The soil temperature showed clear differences between seasons, while there was a significant difference in soil pH,
organic matter, total N concentrations, and available phosphorus between the north- and south-facing stands. The N2 fixation rates during the growing season varied from 0.1 to 37.5 kg N ha−1 month−1 depending on the sampling location and time. The annual N2 fixation rate (kg N per hectare per year) was 112.3 and 23.2 for the north- and south-facing stands, respectively. The differences
in N2 fixation rate between the two stands were due mainly to the differences in total nodule biomass. 相似文献
106.
107.
108.
It has been recently that particulate matter (PM) exposure increases the risk and exacerbation of allergic asthma. However, the underlying mechanisms and factors associated with increased allergic responses remain elusive. We evaluated IL‐23 and IL‐23R (receptor) expression, as well as changes in the asthmatic phenotype in mice administered PM and a low dose of house dust mite (HDM). Next, changes in the phenotype and immune responses were evaluated after intranasal administration of anti‐IL‐23 antibody during co‐exposure to PM and low‐dose HDM. We also performed in vitro experiments to investigate the effect of IL‐23. IL‐23 expression was significantly increased in Epcam+CD45− and CD11c+ cells, while that of IL‐23R was increased in Epcam+CD45− cells only in mice administered PM and low‐dose HDM. Administration of anti‐IL‐23 antibody led to decreased airway hyperresponsiveness, eosinophils, and activation of dendritic cells, reduced populations of Th2 Th17, ILC2, the level of IL‐33 and granulocyte‐macrophage colony‐stimulating factor (GM‐CSF). Inhibition of IL‐23 in PM and low‐dose HDM stimulated airway epithelial cell line resulted in decreased IL‐33, GM‐CSF and affected ILC2 and the activation of BMDCs. PM augmented the phenotypes and immunologic responses of asthma even at low doses of HDM. Interestingly, IL‐23 affected immunological changes in airway epithelial cells. 相似文献
109.
Kalaiselvi Duraisamy Areum Ha Jongmun Kim Ae Ran Park Bora Kim Chan Woo Song Hyohak Song Jin-Cheol Kim 《The Plant Pathology Journal》2022,38(3):182
Turfgrass, the most widely grown ornamental crop, is severely affected by fungal pathogens including Sclerotinia homoeocarpa, Rhizoctonia solani, and Magnaporthe poae. At present, turfgrass fungal disease management predominantly relies on synthetic fungicide treatments. However, the extensive application of fungicides to the soil increases residual detection frequency, raising concerns for the environment and human health. The bacterial volatile compound, 2,3-butanediol (BDO), was found to induce plant resistance. In this study, we evaluated the disease control efficacy of a combination of stereoisomers of 2,3-BDO and commercial fungicides against turfgrass fungal diseases in both growth room and fields. In the growth room experiment, the combination of 0.9% 2R,3R-BDO (levo) soluble liquid (SL) formulation and 9% 2R,3S-BDO (meso) SL with half concentration of fungicides significantly increased the disease control efficacy against dollar spot and summer patch disease when compared to the half concentration of fungicide alone. In field experiments, the disease control efficiency of levo 0.9% and meso 9% SL, in combination with a fungicide, was confirmed against dollar spot and large patch disease. Additionally, the induction of defense-related genes involved in the salicylic acid and jasmonic acid/ethylene signaling pathways and reactive oxygen species detoxification-related genes under Clarireedia sp. infection was confirmed with levo 0.9% and meso 9% SL treatment in creeping bentgrass. Our findings suggest that 2,3-BDO isomer formulations can be combined with chemical fungicides as a new integrated tool to control Clarireedia sp. infection in turfgrass, thereby reducing the use of chemical fungicides. 相似文献
110.