199 research outputs found
Selenium and Health: An Update on the Situation in the Middle East and North Africa.
Selenium (Se) is an important trace element that should be present in the diet of all age groups to provide an adequate intake. Se is incorporated in 25 known selenoproteins, which mediate the biological effects of Se including, immune response regulation, maintenance of thyroid function, antioxidant defense, and anti-inflammatory actions. A balanced intake of Se is critical to achieve health benefits because depending on its status, Se has been found to play physiological roles or contribute to the pathophysiology of various diseases including, neurodegenerative diseases, diabetes, cancer, and cardiovascular disorders. Se status and intake are very important to be known for a specific population as the levels of Se are highly variable among different populations and regions. In the Middle East and North African (MENA) region, very little is known about the status of Se. Studies available show that Se status is widely variable with some countries being deficient, some over sufficient, and some sufficient. This variability was apparent even within the same country between regions. In this review, we summarized the key roles of Se in health and disease and discussed the available data on Se status and intake among countries of the MENA region
Molecular Characterization and Study of Genetic Relationships among local Cultivars of the Moroccan fig (Ficus carica L.) using Microsatellite and ISSR Markers
Molecular characterization of Moroccan local fig (Ficus carica L.) germplasm was performed on the cultivars present in a collection of the National School of Agriculture of Meknes. A total of 22 fig samples were analysed using 7 ISSR primers and 9 loci S.S.R. A total of 54 I.S.S.R. polymorphic bands with an average of 8 per primers and 42 S.S.R. alleles with means 5 alleles per locus were revealed by these analyses. The ISSR markers allowed distinguishing 22 molecular profiles and S.S.R. loci differentiated between 21 different profiles. Pairwise Comparing, 87% of cultivars pairs were differentiated by 7 to 24 alleles and 89% by 9 to 29 ISSR bands. The statistical analysis and genetic distances have shown a wide molecular diversity in the collection, where the average observed heterozygosity was 0.42. The average similarity between cultivars is 70% using SSR markers and 71.6 for ISSR markers.
The same SSR profile was obtained for Nabout1 and Nabout2 with 0 allele difference. Small differences of 1 to 6 alleles were obtained among cultivars which have the same names, which presumably corresponds to somaclonal variations obtained through intense vegetative propagation over long periods, while the differences over 7 alleles suggests the problems of homonyms
Genome reorganization of the GmSHMT gene family in soybean showed a lack of functional redundancy in resistance to soybean cyst nematode
In soybeans, eighteen members constitute the serine hydroxymethyltransferase (GmSHMT) gene family, of which the cytosolic-targeted GmSHMT08c member has been reported to mediate resistance to soybean cyst nematode (SCN). This work presents a comprehensive study of the SHMT gene family members, including synteny, phylogeny, subcellular localizations, haplotypes, protein homology modeling, mutational, and expression analyses. Phylogenetic analysis showed that SHMT genes are divided into four classes refecting their subcellular distribution (cytosol, nucleus, mitochondrion, and chloroplast). Subcellular localization of selected GmSHMT members supports their in-silico predictions and phylogenetic distribution. Expression and functional analyses showed that GmSHMT genes display many overlapping, but some divergent responses during SCN infection. Furthermore, mutational analysis reveals that all isolated EMS mutants that lose their resistance to SCN carry missense and nonsense mutations at the GmSHMT08c, but none of the Gmshmt08c mutants carried mutations in the other GmSHMT genes. Haplotype clustering analysis using the whole genome resequencing data from a collection of 106 diverse soybean germplams (15X) was performed to identify allelic variants and haplotypes within the GmSHMT gene family. Interestingly, only the cytosolic-localized GmSHMT08c presented SNP clusters that were associated with SCN resistance, supporting our mutational analysis. Although eight GmSHMT members respond to the nematode infestation, functional and mutational analysis has shown the absence of functional redundancy in resistance to SCN. Structural analysis and protein homology modeling showed the presence of spontaneous mutations at important residues within the GmSHMT proteins, suggesting the presence of altered enzyme activities based on substrate afnities. Due to the accumulation of mutations during the evolution of the soybean genome, the other GmSHMT members have undergone neofunctionalization and subfunctionalization events
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