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41.
Aritra Bose Daniel E Platt Laxmi Parida Petros Drineas Peristera Paschou 《Molecular biology and evolution》2021,38(5):1809
India represents an intricate tapestry of population substructure shaped by geography, language, culture, and social stratification. Although geography closely correlates with genetic structure in other parts of the world, the strict endogamy imposed by the Indian caste system and the large number of spoken languages add further levels of complexity to understand Indian population structure. To date, no study has attempted to model and evaluate how these factors have interacted to shape the patterns of genetic diversity within India. We merged all publicly available data from the Indian subcontinent into a data set of 891 individuals from 90 well-defined groups. Bringing together geography, genetics, and demographic factors, we developed Correlation Optimization of Genetics and Geodemographics to build a model that explains the observed population genetic substructure. We show that shared language along with social structure have been the most powerful forces in creating paths of gene flow in the subcontinent. Furthermore, we discover the ethnic groups that best capture the diverse genetic substructure using a ridge leverage score statistic. Integrating data from India with a data set of additional 1,323 individuals from 50 Eurasian populations, we find that Indo-European and Dravidian speakers of India show shared genetic drift with Europeans, whereas the Tibeto-Burman speaking tribal groups have maximum shared genetic drift with East Asians. 相似文献
42.
The aerial parts of Loxothysanus sinuatus afforded in addition to known compounds nine new pseudoguaianolides, three guaianolides and five carabrone derivatives. The structures were elucidated by spectroscopic methods. The chemotaxonomy is discussed briefly. The configurations of two guaianolides were corrected. 相似文献
43.
M. Anila H. K. Mahadeva Swamy R. R. Kale V. P. Bhadana M. S. Anantha Brajendra S. K. Hajira C. H. Balachiranjeevi M. Ayyappa Dass S. Bhaskar T. Dilip K. Pranathi M. B. V. N. Kousik G. Harika K. Swapnil K. Chaitra B. Laxmi Prasanna E. Punniakotti Pragya Sinha G. Rekha V. Abhilash Kumar S. M. Balachandran M. S. Madhav Archana Giri B. C. Viraktamath R. M. Sundaram 《Molecular breeding : new strategies in plant improvement》2018,38(12):147
MTU 1010 is a high-yielding mega-variety of rice grown extensively in India. However, it does not perform well in soils with low phosphorus (P) levels. With an objective to improve MTU 1010 for tolerance to low soil P, we have transferred Pup1, a major quantitative trait locus (QTL) associated with tolerance from another mega-variety, Swarna, through marker-assisted backcross breeding (MABB). Foreground selection of the F1 and backcross plants was performed with the co-dominant, closely linked CAPS marker, K20-2, while two flanking markers RM28011 and RM28157 were utilized for recombinant selection. At each backcross generation, positive plants were also analyzed with a set of 85 parental polymorphic SSR markers to identify the QTL-positive plants possessing maximum introgression of MTU 1010 genome. At BC2F1, the best backcross plant was selfed to generate BC2F2s. Among them, the plants homozygous for Pup1 (n?=?22) were reconfirmed using the functional marker for Pup1, viz., K46-1, and they were advanced through pedigree method of selection until BC2F6 generation. A total of five elite BC2F6 lines, possessing Pup1 and phenotypically similar to MTU 1010, were screened in the low soil P plot and normal plot (with optimum soil P levels) during wet season, 2016. All the selected lines showed better performance under low P soil with more number of productive tillers, better root system architecture, and significantly higher yield (>?390%) as compared to MTU 1010. Further, under normal soil, the lines were observed to be similar to or better than MTU 1010 for most of the agro-morphological traits and yield. This study represents the successful application of marker-assisted selection for improvement of tolerance to low soil P in a high-yielding Indian rice variety. 相似文献
44.
G. Rekha V. Abhilash Kumar B. C. Viraktamath K. Pranathi M. B. V. N. Kousik B. Laxmi Prasanna C. Backiyalakshmi Pragya Sinha R. K. Ravindra S. Bhaskar S. K. Hajira C. H. Balachiranjeevi K. Swapnil R. Rambabu G. Harika E. Punniakotti M. Anila H. K. Mahadev T. Dilip Kumar A. Yugander K. Chaitra M. Praveen K. R. Madhavi M. S. Prasad G. S. Laha C. N. Neeraja S. M. Balachandran P. Senguttuvel R. A. Fiyaz J. Badri A. Giri L. V. Subba Rao V. Ravindra Babu R. M. Sundaram 《Journal of plant biochemistry and biotechnology.》2018,27(4):463-472
Improved Samba Mahsuri (ISM) is a popular, high-yielding, bacterial blight resistant rice variety possessing medium-slender grain type. As ISM is highly susceptible to blast disease of rice, through the present study we have transferred two major blast resistance genes, Pi2 and Pi54 into the elite variety by marker-assisted backcross breeding. The two blast resistance genes were transferred to ISM through sets of backcrosses. In every backcross generation, PCR-based markers, specific for the blast resistance genes (Pi2 and Pi54) and bacterial blight resistance genes (Xa21, xa13 and xa5) were utilized for foreground selection, while a set of 144 parental polymorphic SSR markers were used for background selection and backcrossing was carried out until BC2 generation. A solitary BC2F1 plant possessing Pi2 or Pi54 along with Xa21, xa13 and xa5 and >?90% recovery of ISM genome was selected from the two sets of backcrosses were crossed and the intercross F1s (ICF1s) thus obtained were selfed to generate ICF2s. Homozygous ICF2 plants carrying all the five resistance genes were identified through markers and advanced through selfing till ICF5 generation by adopting pedigree method of selection. Three best lines at ICF5, possessing excellent resistance against bacterial blight and blast and closely resembling or superior to ISM in terms of grain quality: yield and agro-morphological traits have been identified and advanced for multi-location trials. 相似文献
45.
Ferdinand Bohlmann Laxmi N. Misra Jasmin Jakupovic Robert M. King Harold Robinson 《Phytochemistry》1985,24(6):1315-1318
The aerial parts of Helenium amarum afforded, in addition to compounds reported previously, several known sesquiterpene lactones as well as some new ones, two pseudoguaianolides and a complex mixture of guaianolide α-arabinopyranosides, which differed in the position of the double bond, the configuration at C-8 and the position of an acetate group in the sugar moiety. Furthermore seco-caryophyllenes and phenylpropane derivatives were isolated. The structures were elucidated by spectroscopic methods and few chemical transformations. 相似文献
46.
The aerial parts of Dugaldia integrifolia afforded, in addition to acetylhymenograndin, floribundin, hymenoxon and isotelekin, three new seco-helenanolides and two derivatives of silphinene, one being isolated previously from Dugaldia hoopesii 相似文献
47.
Functionally related genes often appear in each other's neighborhood on the genome; however, the order of the genes may not be the same. These groups or clusters of genes may have an ancient evolutionary origin or may signify some other critical phenomenon and may also aid in function prediction of genes. Such gene clusters also aid toward solving the problem of local alignment of genes. Similarly, clusters of protein domains, albeit appearing in different orders in the protein sequence, suggest common functionality in spite of being nonhomologous. In the paper, we address the problem of automatically discovering clusters of entities, be they genes or domains: we formalize the abstract problem as a discovery problem called the (pi)pattern problem and give an algorithm that automatically discovers the clusters of patterns in multiple data sequences. We take a model-less approach and introduce a notation for maximal patterns that drastically reduces the number of valid cluster patterns, without any loss of information, We demonstrate the automatic pattern discovery tool on motifs on E. Coli protein sequences. 相似文献
48.
S. Vijaya Laxmi P. Anil G. Rajitha Asha Jyothi Rao Peter A. Crooks B. Rajitha 《Journal of chemical biology》2016,9(4):97-106
In the search of efficient anticancer agents, here, new 5-(4-alkylbenzyledene)thiazolidine-2,4-dione derivatives (5a–g) have been successfully synthesized and characterized and are evaluated for anticancer and antimicrobial activities using DNA cleavage studies. In vitro studies on anticancer activity of compound 5d (NSC: 768619/1) was done against the full panel of 60 human tumor cell lines. The five-level dose activity results revealed that, the compound 5d was active against all the cell lines, it has shown potential activity against leukemia SR (GI50: 2.04 μM), non-small cell lung cancer NCI-H522 (GI50: 1.36 μM), colon cancer COLO 205 (GI50: 1.64 μM), CNS cancer SF-539 (GI50: 1.87 μM), melanoma SK-MEL-2 (GI50: 1.64 μM), ovarian cancer OVCAR-3 (GI50: 1.87 μM), renal cancer RXF 393 (GI50: 1.15 μM), prostate cancer PC-3 (GI50: 1.90 μM), and breast cancer MDA-MB-468(GI50: 1.11 μM). DNA cleavage studies revealed that at 50 μg/mL concentration, partial DNA digestion was observed and when the concentration is increasing to threefold (150 μg/mL), complete linear DNA digestion and partial supercoiled DNA digestion was observed. Further antimicrobial studies indicate that all the synthesized compounds except compound 5a possess prominent activity against all the screened microbial species. This study throws a ray of light in the field of anticancer drugs. 相似文献
49.
50.
Comprehensive study of interaction between biocompatible PEG‐InP/ZnS QDs and bovine serum albumin
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M. S. Sannaikar Laxmi S. Inamdar G. H. Pujar M. N. Wari Nafisa H. Balasinor S. R. Inamdar 《Luminescence》2018,33(3):495-504
Polyethylene glycol (PEG) surface modified biocompatible InP/ZnS quantum dots (QDs) act as a potential alternative for conventional carcinogenic cadmium‐based quantum dots for in vivo and in vitro studies. Comprehensively, we studied the interaction between a model protein bovine serum albumin (BSA) and PEGylated toxic free InP/ZnS QDs using various spectroscopic tools such as absorption, fluorescence quenching, time resolved and synchronous fluorescence spectroscopic measurements. These studies principally show that tryptophan (Trp) residues of BSA have preferable binding affinity towards PEG‐InP/ZnS QDs surface and a blue shift in Trp fluorescence emission is a signature of conformational changes in its hydrophobic microenvironment. Photoluminescence (PL) intensity of Trp is quenched by ground state complex formation (static quenching) at room temperature. However, InP/ZnS@BSA conjugates become unstable with increasing temperature and PL intensity of Trp is quenched via dynamic quenching by PEG‐InP/ZnS QDs. Experimentally determined thermodynamic parameters for these conjugates have shown spontaneity, entropy driven and exothermic nature of bio‐conjugation. The calculated binding affinity (n ? 1, Hill coefficient) suggest that the affinity of InP/ZnS QDs for a BSA protein is not dependent on whether or not other BSA proteins are already bound to the QD surface. Energy transfer efficiency (E), Trp residue to InP/ZnS QDs distances and energy transfer rate (kT) were all obtained from FÖrster resonance energy. 相似文献