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21.
Sambasivam Periyannan Urmil Bansal Harbans Bariana Karin Deal Ming-Cheng Luo Jan Dvorak Evans Lagudah 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2014,127(4):947-955
Key message
Fine mapping of the Ug99 effective stem rust resistance gene Sr45 introgressed into common wheat from the D -genome goatgrass Aegilops tauschii.Abstract
Stem rust resistance gene Sr45, discovered in Aegilops tauschii, the progenitor of the D -genome of wheat, is effective against commercially important Puccinia graminis f. sp. tritici races prevalent in Australia, South Africa and the Ug99 race group. A synthetic hexaploid wheat (RL5406) generated by crossing Ae. tauschii accession RL5289 (carrying Sr45 and the leaf rust resistance gene Lr21) with a tetraploid experimental line ‘TetraCanthatch’ was previously used as the source in the transfer of these rust resistance genes to other hexaploid cultivars. Previous genetic studies on hexaploid wheats mapped Sr45 on the short arm of chromosome 1D with the following gene order: centromere–Sr45–Sr33–Lr21–telomere. To identify closely linked markers, we fine mapped the Sr45 region in a large mapping population generated by crossing CS1D5406 (disomic substitution line with chromosome 1D of RL5406 substituted for Chinese Spring 1D) with Chinese Spring. Closely linked markers based on 1DS-specific microsatellites, expressed sequence tags and AFLP were useful in the delineation of the Sr45 region. Sequences from an AFLP marker amplified a fragment that was linked with Sr45 at a distance of 0.39 cM. The fragment was located in a bacterial artificial chromosome clone of contig (ctg)2981 of the Ae. tauschii accession AL8/78 physical map. A PCR marker derived from clone MI221O11 of ctg2981 amplified 1DS-specific sequence that harboured an 18-bp indel polymorphism that specifically tagged the Sr45 carrying haplotype. This new Sr45 marker can be combined with a previously reported marker for Lr21, which will facilitate selecting Sr45 and Lr21 in breeding populations. 相似文献22.
23.
Saikat Boliar Supratik Das Manish Bansal Brihaspati N. Shukla Shilpa Patil Tripti Shrivastava Sweety Samal Sandeep Goswami C. Richter King Jayanta Bhattacharya Bimal K. Chakrabarti 《PloS one》2015,10(3)
An ideal HIV-1 Env immunogen is expected to mimic the native trimeric conformation for inducing broadly neutralizing antibody responses. The native conformation is dependent on efficient cleavage of HIV-1 Env. The clade B isolate, JRFL Env is efficiently cleaved when expressed on the cell surface. Here, for the first time, we report the identification of a native clade C Env, 4-2.J41 that is naturally and efficiently cleaved on the cell surface as confirmed by its biochemical and antigenic characteristics. In addition to binding to several conformation-dependent neutralizing antibodies, 4-2.J41 Env binds efficiently to the cleavage-dependent antibody PGT151; thus validating its native cleaved conformation. In contrast, 4-2.J41 Env occludes non-neutralizing epitopes. The cytoplasmic-tail of 4-2.J41 Env plays an important role in maintaining its conformation. Furthermore, codon optimization of 4-2.J41 Env sequence significantly increases its expression while retaining its native conformation. Since clade C of HIV-1 is the prevalent subtype, identification and characterization of this efficiently cleaved Env would provide a platform for rational immunogen design. 相似文献
24.
Vallence?Nsabiyera Naeela?Qureshi Harbans?S.?Bariana Debbie?Wong Kerrie?L.?Forrest Mathew?J.?Hayden Urmil?K.?BansalEmail author 《Molecular breeding : new strategies in plant improvement》2016,36(6):65
Leaf rust of wheat, caused by Puccinia triticina, is an important disease throughout the world. The adult plant leaf rust resistance gene Lr48 reported in CSP44 was previously mapped in chromosome 2B, but the marker–gene association was weak. In this study, we confirmed the location of Lr48 to be in the short arm of chromosome 2B and identified closely linked markers suitable for use in breeding. The CSP44/WL711 recombinant inbred line (RIL) population (90 lines) showed monogenic segregation for Lr48. Twelve resistant and 12 susceptible RILs were used for selective genotyping using an iSelect 90K Infinium SNP assay. Closely linked SNPs were converted into Kompetitive allele-specific primers (KASP) and tested on the parental lines. KASP markers giving clear clusters for alternate genotypes were assayed on the entire RIL population. SNP markers IWB31002, IWB39832, IWB34324, IWB72894 and IWB36920 co-segregated with Lr48 and the marker IWB70147 was mapped 0.3 cM proximal to this gene. Closely linked KASP markers were tested on a set of Australian and Nordic wheat genotypes. The amplification of SNP alleles alternate to those linked with Lr48 in the majority of the Australian and Nordic wheat genotypes demonstrated the usefulness of these markers for marker-assisted pyramiding of Lr48 with other rust resistance genes. 相似文献
25.
Bansal Mitaly Adamski Nikolai M. Toor Puneet Inder Kaur Satinder Sharma Achla Srivastava Puja Bansal Urmil Uauy Cristobal Chhuneja Parveen 《Molecular biology reports》2021,48(6):5209-5216
Molecular Biology Reports - Stripe rust and leaf rust are among the most devastating diseases of wheat, limiting its production globally. Wheat wild relatives harbour genetic diversity for new... 相似文献
26.
Bansal Kanika Kaur Amandeep Midha Samriti Kumar Sanjeet Korpole Suresh Patil Prabhu B. 《Antonie van Leeuwenhoek》2021,114(11):1935-1947
Antonie van Leeuwenhoek - We report three yellow-pigmented, Gram-negative, aerobic, rod-shaped, motile bacterial isolates designated as PPL1T, PPL2, and PPL3 from healthy basmati rice seeds.... 相似文献
27.
Arvinder Toor Urmil Bansal Harbans Bariana 《Molecular breeding : new strategies in plant improvement》2013,32(3):699-707
Flag smut, caused by Urocystis agropyri, has been a problem in wheat production, but its incidence has declined with the use of resistant varieties and seed dressing. Diamondbird, an Australian wheat cultivar that carries high levels of resistance to flag smut, was crossed with susceptible Chinese landrace TH3929 and a doubled haploid (DH) population was developed. A linkage map comprising 386 markers was used for detection of genomic regions controlling flag smut resistance. Composite interval mapping identified five quantitative trait loci (QTL) with significant effects for flag smut resistance. QTL QFs.sun-3AL, QFs.sun-6AS, QFs.sun-1BL and QFs.sun-5BS were contributed by Diamondbird. Although TH3929 was susceptible, it contributed a minor QTL QFs.sun-3AS. QTL QFs.sun-3AL and QFs.sun-6AS were detected in both seasons and each explained more than 17 % of the variation in flag smut response. Other QTL QFs.sun-3AS, QFs.sun-1BL and QFs.sun-5BS explained 5–10 % of the phenotypic variation. DH lines that showed low flag smut levels carried combinations of three or more QTL. This is the first report on chromosomal location of flag smut resistance in a modern common wheat cultivar. 相似文献
28.
Abstract Nanosecond scale molecular dynamics simulations have been performed on antiparallel Greek key type d(G7) quadruplex structures with different coordinated ions, namely Na+ and K+ ion, water and Na+ counter ions, using the AMBER force field and Particle Mesh Ewald technique for electrostatic interactions. Antiparallel structures are stable during the simulation, with root mean square deviation values of ~ 1.5 Å from the initial structures. Hydrogen bonding patterns within the G-tetrads depend on the nature of the coordinated ion, with the G-tetrad undergoing local structural variation to accommodate different cations. However, alternating syn-anti arrangement of bases along a chain as well as in a quartet is maintained through out the MD simulation. Coordinated Na+ ions, within the quadruplex cavity are quite mobile within the central channel and can even enter or exit from the quadruplex core, whereas coordinated K+ ions are quite immobile. MD studies at 400K indicate that K+ ion cannot come out from the quadruplex core without breaking the terminal G-tetrads. Smaller grooves in antiparallel structures are better binding sites for hydrated counter ions, while a string of hydrogen bonded water molecules are observed within both the small and large grooves. The hydration free energy for the K+ ion coordinated structure is more favourable than that for the Na+ ion coordinated antiparallel quadruplex structure. 相似文献
29.
30.
Manish Singh Ashima Singh Somanath Kundu Sandhya Bansal Avinash Bajaj 《生物化学与生物物理学报:生物膜》2013,1828(8):1926-1937
We synthesized four cationic bile acid based facial amphiphiles featuring trimethyl ammonium head groups. We evaluated the role of these amphiphiles for cytotoxic activities against colon cancer cells and their membrane interactions by varying charge, hydration and hydrophobicity. The singly charged cationic Lithocholic acid based amphiphile (LCA-TMA1) is most cytotoxic, whereas the triply charged cationic Cholic acid based amphiphile (CA-TMA3) is least cytotoxic. Light microscopy and Annexin-FITC assay revealed that these facial amphiphiles caused late apoptosis. In addition, we studied the interactions of these amphiphiles with model membrane systems by Prodan-based hydration, DPH-based anisotropy, and differential scanning calorimetry. LCA-TMA1 is most hydrophobic with a hard charge causing efficient dehydration and maximum perturbations of membranes thereby facilitating translocation and high cytotoxicity against colon cancer cells. In contrast, the highly hydrated and multiple charged CA-TMA3 caused least membrane perturbations leading to low translocation and less cytotoxicity. As expected, Chenodeoxycholic acid and Deoxycholic acid based amphiphiles (CDCA-TMA2, DCA-TMA2) featuring two charged head groups showed intermediate behavior. Thus, we deciphered that charge, hydration, and hydrophobicity of these amphiphiles govern membrane interactions, translocation, and resulting cytoxicity against colon cancer cells. 相似文献