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101.
The discovery of nucleotide diversity captured as single feature polymorphism (SFP) by using the expression array is a high-throughput and effective method in detecting genome-wide polymorphism. The efficacy of such method was tested in rice, and the results presented in the paper indicate high sensitivity in predicting SFP. The sensitivity of polymorphism detection was further demonstrated by the fact that no biasness was observed in detecting SFP with either single or multiple nucleotide polymorphisms. The high density SFP data that can be generated quite effectively by the current method has promise for high resolution genetic mapping studies, as physical location of features are well-defined on rice genome. 相似文献
102.
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104.
Selvaraj Michael Gomez N. Manikanda Boopathi S. Satheesh Kumar T. Ramasubramanian Zhu Chengsong P. Jeyaprakash A. Senthil R. Chandra Babu 《Acta Physiologiae Plantarum》2010,32(2):355-364
Drought is a major limitation for rice production in rainfed ecosystems. Identifying quantitative trait loci (QTLs) linked
to drought resistance provides opportunity to breed high yielding rice varieties suitable for drought-prone areas. Although
considerable efforts were made in mapping QTLs associated with drought-resistance traits in rice, most of the studies involved
indica × japonica crosses and hence, the drought-resistance alleles were contributed mostly by japonica ecotypes. It is desirable to look for genetic variation within indica ecotypes adapted to target environment (TE) as the alleles from japonica ecotype may not be expressed under lowland conditions. A subset of 250 recombinant inbred lines (RILs) of F8 generation derived from two indica rice lines (IR20 and Nootripathu) with contrasting drought-resistance traits were used to map the QTLs for morpho-physiological
and plant production traits under drought stress in the field in TE. A genetic linkage map was constructed using 101 polymorphic
PCR-based markers distributed over the 12 chromosomes covering a total length of 1,529 cM in 17 linkage groups with an average
distance of 15.1 cM. Composite interval mapping analysis identified 22 QTLs, which individually explained 4.8–32.2% of the
phenotypic variation. Consistent QTLs for drought-resistance traits were detected using locally adapted indica ecotypes, which may be useful for rainfed rice improvement. 相似文献
105.
Wojciech Roczniak Barbara Brodziak-Dopierała Elżbieta Cipora Agata Jakóbik-Kolon Joanna Kluczka Magdalena Babuśka-Roczniak 《Biological trace element research》2017,178(2):201-209
Osteoarthritis causes the degradation of the articular cartilage and periarticular bones. Trace elements influence the growth, development and condition of the bone tissue. Changes to the mineral composition of the bone tissue can cause degenerative changes and fractures. The aim of the research was to determine the content of cadmium (Cd), nickel (Ni), copper (Cu) and zinc (Zn) in the tibia, the femur and the meniscus in men and women who underwent a knee replacement surgery. Samples were collected from 50 patients, including 36 women and 14 men. The determination of trace elements content were performed by ICP-AES method, using Varian 710-ES. Average concentration in the tissues of the knee joint teeth amounted for cadmium 0.015, nickel 0.60, copper 0.89 and zinc 80.81 mg/kg wet weight. There were statistically significant differences in the content of cadmium, copper and zinc in different parts of the knee joint. There were no statistically significant differences in the content of cadmium, nickel, copper and zinc in women and men in the examined parts of the knee joint. Among the elements tested, copper and nickel showed a high content in the connective tissue (the meniscus) compared to the bone tissue (the tibia and the femur). 相似文献
106.
Summary Glutamate (Glu) the major amino acid in mammalian brain and most dietary proteins possesses neurotransmitter as well as neurotoxic properties. We administered monosodium glutamate (MSG) 4 mg/g bwt, sc on postnatal day (PND) 1 through 10 to rats on alternate days or daily and sacrificed them on PND 45 or PND 90 respectively. The activities of glutamate dehydrogenase and aminotransferases were evaluated in the circumventricular organs of brain. Results show that neonatal MSG produces alterations in glutamate metabolism in blood-brain-barrier deficient regions. 相似文献
107.
Punja Harshitha K. Nanjappa Dechamma Pandyanda Babu Nishith Kalladka Krithika Shanti Priya Dias B. Chakraborty Gunimala Rao Sudhindra M. Chakraborty Anirban 《Molecular biology reports》2021,48(6):5093-5097
Molecular Biology Reports - TP53 functions primarily as a tumor suppressor, controlling a myriad of signalling pathways that prevent a cell from undergoing malignant transformation. This tumor... 相似文献
108.
Hyphae of Phyllactinia corylea produce two kinds of special branches on the host surface: adhesion bodies which serve as fungal attachment and stomatopodia which enter the leaf through stomata. Conidial germination on host and non-host surfaces was examined with a scanning electron microscope to explain the stimuli responsible for development of the special branches, and the involvement of host recognition in the process. Conidia germinated within 4 h on host and non-host surfaces, but on non-host surfaces the emergence of the germ tube was not always directed towards the substratum. Adhesion bodies were formed from the tips of germ tubes at the first contact point on host and non-host surfaces. Development of stomatopodia was more specific and they were formed precisely over stomata on the host surface. Stomatopodia-like structures were occasionally formed over finely ridged leaf veins on the host surface and over some fine scratches on synthetic surfaces. The experiments showed that while conidial germination and development of adhesion bodies are in response to contact stimuli, the development of stomatopodia is a response to precise topographical signals, and the directional emergence and attached growth of germ tubes involve host recognition.This revised version was published online in October 2005 with corrections to the Cover Date. 相似文献
109.
Outer-membrane characteristics may determine the survivability of rhizobia under diverse abiotic and biotic stresses. Therefore,
the role of lipopolysaccharides (LPS) and membrane proteins of two stem-nodulating bacteria of Sesbania rostrata (Azorhizobium caulinodans ORS571 and Rhizobium sp. WE7) in determining tolerance towards abiotic and biotic stresses (hydrophobics and phages) was investigated. Outer-membrane
characteristics (LPS and membrane–protein profiles) of ORS571, WE7 and thirteen standard strains were distinct. ORS571 and
WE7 also showed susceptibility towards morphologically distinct phages, i.e., ACSR16 (short-tailed) and WESR29 (long-tailed),
respectively. ORS571 and WE7 were tolerant to hydrophobic compounds (triton X-100, rifampicin, crystal violet and deoxycholate).
To ascertain the role of outer membrane characteristics in stress tolerance, phage-resistant transconjugant mutants of ORS571
(ORS571-M8 and ORS571-M20) and WE7 (WE7-M9) were developed. LPS- and membrane–protein profiles of mutants differed from that
of respective wild types (ORS571 and WE7). In in vitro assay, phages got adsorbed onto purified LPS-membrane protein fractions
of wild types. Phages did not adsorb onto membrane fraction of mutants and standard strains. Mutant with reduced expression
of LPS (ORS571-M20 and WE7-M9) showed reduced tolerance towards hydrophobics. However, the tolerance was unaffected in mutant
(ORS571-M8) where expression of LPS was not reduced but pattern was different. The tolerance level of mutants towards hydrophobics
varied with the expression of LPS, whereas the specificity towards phages is correlated with the specific LPS pattern. 相似文献
110.
A. Pavan-Kumar P. Gireesh-Babu P. P. Suresh Babu A. K. Jaiswar V. Hari Krishna K. Pani Prasasd Aparna Chaudhari S. G. Raje S. K. Chakraborty Gopal Krishna W. S. Lakra 《Molecular biology reports》2014,41(1):447-457
The elasmobranchs (sharks, rays and skates) being the extant survivors of one of the earliest offshoots of the vertebrate evolutionary tree are good model organisms to study the primitive vertebrate conditions. They play a significant role in maintaining the ecological balance and have high economic value. Due to over-exploitation and illegal fishing worldwide, the elasmobranch stocks are being decimated at an alarming rate. Appropriate management measures are necessary for restoring depleted elasmobranch stocks. One approach for restoring stocks is implementation of conservation measures and these measures can be formulated effectively by knowing the evolutionary relationship among the elasmobranchs. In this study, a total of 30 species were chosen for molecular phylogeny studies using mitochondrial cytochrome c oxidase subunit I, 12S ribosomal RNA gene and nuclear Internal Transcribed Spacer 2. Among different genes, the combined dataset of COI and 12S rRNA resulted in a well resolved tree topology with significant bootstrap/posterior probabilities values. The results supported the reciprocal monophyly of sharks and batoids. Within Galeomorphii, Heterodontiformes (bullhead sharks) formed as a sister group to Lamniformes (mackerel sharks): Orectolobiformes (carpet sharks) and to Carcharhiniformes (ground sharks). Within batoids, the Myliobatiformes formed a monophyly group while Pristiformes (sawfishes) and Rhinobatiformes (guitar fishes) formed a sister group to all other batoids. 相似文献