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901.
Jianhui Wu Qingdong Zeng Qilin Wang Shengjie Liu Shizhou Yu Jingmei Mu Shuo Huang Hanan Sela Assaf Distelfeld Lili Huang Dejun Han Zhensheng Kang 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2018,131(7):1481-1496
Key message
NGS-assisted super pooling emerging as powerful tool to accelerate gene mapping and haplotype association analysis within target region uncovering specific linkage SNPs or alleles for marker-assisted gene pyramiding.Abstract
Conventional gene mapping methods to identify genes associated with important agronomic traits require significant amounts of financial support and time. Here, a single nucleotide polymorphism (SNP)-based mapping approach, RNA-Seq and SNP array assisted super pooling analysis, was used for rapid mining of a candidate genomic region for stripe rust resistance gene Yr26 that has been widely used in wheat breeding programs in China. Large DNA and RNA super-pools were genotyped by Wheat SNP Array and sequenced by Illumina HiSeq, respectively. Hundreds of thousands of SNPs were identified and then filtered by multiple filtering criteria. Among selected SNPs, over 900 were found within an overlapping interval of less than 30 Mb as the Yr26 candidate genomic region in the centromeric region of chromosome arm 1BL. The 235 chromosome-specific SNPs were converted into KASP assays to validate the Yr26 interval in different genetic populations. Using a high-resolution mapping population (>?30,000 gametes), we confined Yr26 to a 0.003-cM interval. The Yr26 target region was anchored to the common wheat IWGSC RefSeq v1.0 and wild emmer WEWSeq v.1.0 sequences, from which 488 and 454 kb fragments were obtained. Several candidate genes were identified in the target genomic region, but there was no typical resistance gene in either genome region. Haplotype analysis identified specific SNPs linked to Yr26 and developed robust and breeder-friendly KASP markers. This integration strategy can be applied to accelerate generating many markers closely linked to target genes/QTL for a trait of interest in wheat and other polyploid species.902.
The objective of the present study was to synthesize monomethoxypolyethyleneglycol-5000 cholesteryl ester [PEG–CH] as a cost-effective
substitute for polyethyleneglycol–phosphatidylethanolamine and to evaluate the influence of its incorporation in liposomal
bilayers for surface modification. PEG–CH was synthesized and characterized by infrared (IR), proton nuclear magnetic resonance
spectroscopy (1H NMR), and differential scanning calorimetry (DSC) studies. Influence of incorporation of PEG–CH in liposomes was evaluated
on various parameters such as zeta potential, DSC, and encapsulation efficiency of a hydrophilic drug pentoxyfylline. Conventional
and PEG–CH containing pentoxyfylline liposomes were formulated and their stability was evaluated at 4°C for 3 months. PEG–CH
could be successfully synthesized with good yields and the structure was confirmed by IR, DSC, and 1H NMR. The incorporation of PEG–CH in liposomes resulted in reduction of the zeta potential and broadening of the DSC endotherm.
Furthermore, incorporation of PEG–CH in liposomes decreased the encapsulation efficiency of pentoxifylline in liposomes when
compared to conventional liposomes. Conventional and PEG–CH containing pentoxyfylline liposomes did not show any signs of
pentoxyfylline degradation when stored at 4°C for 3 months. 相似文献
903.
Alcantarea martinellii is described and illustrated as a new species endemic to Serra dos Órgãos, Petrópolis, Rio de Janeiro State, Brazil. The presence of a simple and erect inflorescence concomitant with a conspicuous water impounding rosette is an unreported combination of characters for Alcantarea. This new lithophytic taxon is unique, with no obvious close relative, but it is similar to A. benzingii, A. farneyi, and A. hatschbachii, which also have unbranched inflorescences. 相似文献
904.
Qiuchi Wan Zhuo Zheng Kangyou Huang Erwan Guichoux Rémy J. Petit 《Tree Genetics & Genomes》2017,13(4):73
Subtropical East Asia harbours a large plant diversity that is often attributed to allopatric speciation in this topographically complex region characterized by a relative climate stability. Here, we use observations of Platycarya, a widespread subtropical Asian tree genus, to explore the consequences of past climate stability on species’ evolutionary history in subtropical China. This genus has a controversial taxonomy: while it is now prevailingly treated as monotypic, two species have been originally described, Platycarya strobilacea and P. longipes. Previous information from species distribution models, fossil pollen data and genetic data based on chloroplast DNA (cpDNA) were integrated with newly obtained genetic data from the two putative species. We used both cpDNA (psbA-trnH and trnL-F intergenic spacers, including a partial trnL gene sequence) and nuclear markers. The latter included sequences of the internal transcribed spacer region (ITS1–5.8S–ITS2) of the nuclear ribosomal DNA and random genomic single nucleotide polymorphisms. Using these nuclear genetic markers, we found interspecific genetic divergence fitting with the ‘two species’ scenario and geographically structured intraspecific variation. Using cpDNA markers, we also found geographically structured intraspecific variation. Despite deep inter- and intraspecific genetic divergence, we detected genetic admixture in southwest China. Overall, our findings of genetic divergence within Platycarya support the hypothesis of allopatric speciation. However, episodes of population interconnection were identified, at least in southwest China, suggesting that the genus has had a dynamic population history. 相似文献
905.
Camilios-Neto D Bugay C de Santana-Filho AP Joslin T de Souza LM Sassaki GL Mitchell DA Krieger N 《Applied microbiology and biotechnology》2011,89(5):1395-1403
Rhamnolipid biosurfactants are attracting attention due to their low toxicity, high biodegradability, and good ecological
acceptability. However, production in submerged culture is made difficult by severe foaming problems. Solid-state cultivation
(SSC) is a promising alternative production method. In the current work, we report the optimization of rhamnolipid production
by Pseudomonas aeruginosa UFPEDA 614 on a solid substrate containing sugarcane bagasse and corn bran. The best rhamnolipid production, 45 g/l of impregnating
solution used, was obtained with a 50:50 (m/m) mixture of sugarcane bagasse and corn bran supplemented with an impregnating
solution containing 6% (v/v) of each of glycerol and soybean oil. This level is comparable with those of previous studies
undertaken in solid-state cultivation; the composition of the biosurfactant is similar, but our medium is cheaper. Our work
therefore provides a suitable basis for future studies of the development of an SSC-based process for rhamnolipid production. 相似文献
906.
Marissa Gowrie 《Aerobiologia》2011,27(4):353-356
There are a number of possible links between airborne pollen and respiratory disease that remain underappreciated by both the scientific community and health care providers within the Latin American and Caribbean region. A few regional studies have assimilated some preliminary information on this association, and most recently research on interactions between airborne pollen and pediatric asthma on the Caribbean island of Trinidad has shown critical areas that require further investigation. Pollen samples were collected over a 2-year period using a Burkard 7 Day Recording Volumetric Spore Sampler. Corresponding pediatric asthma data were recorded at a nearby medical hospital. Results indicated that the wet season showed higher pollen concentrations (82 pollen per cubic meter/day) than the dry season (53 pollen per cubic meter/day), and several pollen taxa were observed. An association between airborne pollen concentrations and pediatric asthma emergency room visits was suggested incorporating a threshold and lag period. 相似文献
907.
908.
Rupali M. Khadake Prabhakar K. Ranjekar Abhay M. Harsulkar 《Molecular biotechnology》2009,42(2):168-174
The Δ12 desaturase represents a diverse gene family in plants and is responsible for conversion of oleic acid (18:1) to linoleic
acid (18:2). Several members of this family are known from plants like Arabidopsis and Soybean. Using primers from conserved C- and N-terminal regions, we have cloned a novel Δ12 desaturase gene amplified
from flax genomic DNA, denoted as LuFAD2-2. This intron-less gene is 1,149-base pair long encoding 382 amino acids—putative membrane-bound Δ12 desaturase protein. Sequence
comparisons show that the novel sequence has 85% similarity with previously reported flax Δ12 desaturase at amino acid level
and shows typical features of membrane-bound desaturase such as three conserved histidine boxes along with four membrane-spanning
regions that are universally present among plant desaturases. The signature amino acid sequence ‘YNNKL’ was also found to
be present at the N terminus of the protein, which is necessary and sufficient for ER localization of enzyme. Neighbor-Joining
tree generated from the sequence alignment grouped LuFAD2-2 among the other FAD2 sequences from Ricinus, Hevea, Jatropha, and Vernicia. When LuFAD2-2 and LuFAD2 were expressed in Saccharomyces cerevisiae, they could convert the oleic acid to linoleic acid, with an average conversion rate of 5.25 and 8.85%, respectively. However,
exogenously supplied linoleic acid was feebly converted to linolenic acid suggesting that LuFAD2-2 encodes a functional FAD2 enzyme and has substrate specificity similar to LuFAD2. 相似文献
909.
The Basidiomycotine fungi Meira geulakonigii, Meira argovae and Acaromyces ingoldii were assayed in the laboratory against five species of herbivorous mites: Phyllocoptruta oleivora (Eriophyidae), Panonychus
citri, Eutetranychus
orientalis, Tetranychus
urticae and Tetranychus
cinnabarinus (all four Tetranychidae). All fungi caused significantly high mortality rates (as compared to controls) after 14 days, some
after 1 week. Phyllocoptruta oleivora was the most susceptible, showing >80% mortality even after 1 week. In a field trial, grapefruits sprayed either once a month
or once a season with M. geulakonigii had significantly fewer P. oleivora and less damage than unsprayed fruit. These results suggest that M. geulakonigii may protect grapefruits against the injurious P. oleivora. 相似文献
910.
Julia Martínez-Blanco Silvia Forin Matthias Finkbeiner 《The International Journal of Life Cycle Assessment》2018,23(1):159-163