11 research outputs found
HIV-2 integrase polymorphisms and longitudinal genotypic analysis of HIV-2 infected patients failing a raltegravir-containing regimen.
To characterize the HIV-2 integrase gene polymorphisms and the pathways to resistance of HIV-2 patients failing a raltegravir-containing regimen, we studied 63 integrase strand transfer inhibitors (INSTI)-naïve patients, and 10 heavily pretreated patients exhibiting virological failure while receiving a salvage raltegravir-containing regimen. All patients were infected by HIV-2 group A. 61.4% of the integrase residues were conserved, including the catalytic motif residues. No INSTI-major resistance mutations were detected in the virus population from naïve patients, but two amino acids that are secondary resistance mutations to INSTIs in HIV-1 were observed. The 10 raltegravir-experienced patients exhibited resistance mutations via three main genetic pathways: N155H, Q148R, and eventually E92Q - T97A. The 155 pathway was preferentially used (7/10 patients). Other mutations associated to raltegravir resistance in HIV-1 were also observed in our HIV-2 population (V151I and D232N), along with several novel mutations previously unreported. Data retrieved from this study should help build a more robust HIV-2-specific algorithm for the genotypic interpretation of raltegravir resistance, and contribute to improve the clinical monitoring of HIV-2-infected patients
Genomic Designing of Pearl Millet:A Resilient Crop for Arid and Semi-arid Environments
Pearl millet [Pennisetum glaucum (L.) R. Br.; Syn. Cenchrus americanus
(L.) Morrone] is the sixth most important cereal in the world. Today, pearl
millet is grown on more than 30 million ha mainly in West and Central Africa and
the Indian sub-continent as a staple food for more than 90 million people in agriculturally
marginal areas. It is rich in proteins and minerals and has numerous
health benefits such as being gluten-free and having slow-digesting starch. It is
grown as a forage crop in temperate areas. It is drought and heat tolerant, and a
climate-smart crop that can withstand unpredictable variability in climate. However,
research on pearl millet improvement is lagging behind other major cereals mainly
due to limited investment in terms of man and money power. So far breeding
achievements include the development of cytoplasmic male sterility (CMS),
maintenance counterparts (rf) system and nuclear fertility restoration genes (Rf) for
hybrid breeding, dwarfing genes for reduced height, improved input responsiveness,
photoperiod neutrality for short growing season, and resistance to important
diseases. Further improvement of pearl millet for genetic yield potential, stress
tolerance, and nutritional quality traits would enhance food and nutrition security
for people living in agriculturally dissolute environments. Application of molecular
technology in the pearl millet breeding program has a promise in enhancing the
selection efficiency while shortening the lengthy phenotypic selection process ultimately improving the rate of genetic gains. Linkage analysis and genome-wide
association studies based on different marker systems in detecting quantitative trait
loci (QTLs) for important agronomic traits are well demonstrated. Genetic
resources including wild relatives have been categorized into primary, secondary
and tertiary gene pools based on the level of genetic barriers and ease of gene
introgression into pearl millet. A draft on pearl millet whole genome sequence was
recently published with an estimated 38,579 genes annotated to establish
genomic-assisted breeding. Resequencing a large number of germplasm lines and
several population genomic studies provided a valuable insight into population
structure, genetic diversity and domestication history of the crop. Successful
improvement in combination with modern genomic/genetic resources, tools and
technologies and adoption of pearl millet will not only improve the resilience of
global food system through on-farm diversification but also dietary intake which
depends on diminishingly fewer crops