The antidepressant-like effect of Ocimum basilicum in an animal model of depression

We investigated the efficacy of Ocimum basilicum (OB) essential oils for treating depression related behavioral, biochemical and histopathological changes caused by exposure to chronic unpredictable mild stress (CUMS) in mice and to explore the mechanism underlying the pathology. Male albino mice were divided into four groups: controls; CUMS; CUMS plus fluoxetine, the antidepressant administered for pharmacological validation of OB; and CUMS plus OB. Behavioral tests included the forced swim test (FST), elevated plus-maze (EPM) and the open ?eld test (OFT); these tests were performed at the end of the experiment. We assessed serum corticosterone level, protein, gene and immunoexpression of brain-derived neurotropic factor (BDNF) and glucocorticoid receptors (GRs) as well as immunoexpression of glial fibrillary acidic protein (GFAP), Ki67, caspase-3 in the hippocampus. CUMS caused depression in the mice as evidenced by prolonged immobility in the FST, prolonged time spent in the open arms during the EPM test and reduction of open field activity in the OFT. OB ameliorated the CUMS induced depressive status. OB significantly reduced the corticosterone level and up-regulated protein and gene expressions of BDNF and GR. OB reduced CUMS induced hippocampal neuron atrophy and apoptosis, and increased the number of the astrocytes and new nerve cells. OB significantly increased GFAP-positive cells as well as BDNF and GR immunoexpression in the hippocampus.     

Reduced representation genome sequencing reveals patterns of genetic diversity and selection in apple

Identifying DNA sequence variations is a fundamental step towards deciphering the genetic basis of traits of interest.Here,a total of 20 cultivated and 10 wild apples were genotyped using specific-locus amplified fragment sequencing,and 39,635 single nucleotide polymorphisms with no missing genotypes and evenly distributed along the genome were selected to investigate patterns of genome-wide genetic variations between cultivated and wild apples.Overall,wild apples displayed higher levels of genetic diversity than cultivated apples.Linkage disequilibrium(LD) decays were observed quite rapidly in cultivated and wild apples,with an r~2-value below 0.2 at 440 and 280 bp,respectively.Moreover,bidirectional gene flow and different distribution patterns of LD blocks were detected between domesticated and wild apples.Most LD blocks unique to cultivated apples were located within QTL regions controlling fruit quality,thus suggesting that fruit quality had probably undergone selection during apple domestication.The genome of the earliest cultivated apple in China,Nai,was highly similar to that of Malus sieversii,and contained a small portion of genetic material from other wild apple species.This suggested that introgression could have been an important driving force during initial domestication of apple.These findings will facilitate future breeding and genetic dissection of complex traits in apple.     

Immunogenicity of nuclear-encoded LTB:ST fusion protein from Escherichia coli expressed in tobacco plants

Enterotoxigenic Escherichia coli (ETEC) is one of the main causative agents of diarrhea in infants and for travelers. Inclusion of a heat-stable (ST) toxin into vaccine formulations is mandatory as most ETEC strains can produce both heat-labile (LT) and ST enterotoxins. In this study, a genetic fusion gene encoding for an LTB:ST protein has been constructed and transferred into tobacco via Agrobacterium tumefaciens-mediated transformation. Transgenic tobacco plants carrying the LTB:ST gene are then subjected to GM1-ELISA revealing that the LTB:ST has assembled into pentamers and displays antigenic determinants from both LTB and ST. Protein accumulation of up to 0.05% total soluble protein is detected. Subsequently, mucosal and systemic humoral responses are elicited in mice orally dosed with transgenic tobacco leaves. This has suggested that the plant-derived LTB:ST is immunogenic via the oral route. These findings are critical for the development of a plant-based vaccine capable of eliciting broader protection against ETEC and targeting both LTB and ST. Features of this platform in comparison to transplastomic approaches are discussed.     

Genetic diversity and population structure of Moringa oleifera

Moringa is a genus of the tropical flowering plant family Moringaceae containing 13 diverse species. Among the different species, only Moringa oleifera L. is cultivated. This species has great potential in serving as a high-value crop for food, medicinal products, as well as fodder for animals, particularly in developing tropical regions of the world. In this study, the genetic diversity and population structure of world-wide collections of M. oleifera were investigated using DNA markers. A total of 19 microsatellite or simple sequence repeat (SSR) markers along with a partial sequence of the chloroplast gene atpB were used to study genetic diversity within 161 accessions of M. oleifera collected from Asia, Africa, North and South America, and the Caribbean. On average, 8.3 alleles/per SSR were amplified in each accession. A total number of 158 alleles were detected in 131 accessions collected from the wild in Pakistan and from 30 accessions obtained from ECHO (Florida). Observed heterozygosity varied from 0.16 to 0.86, with an average of 0.58, while the average PIC value was 0.59. Partial sequencing of chloroplast genes of 43 of 161 plants generated mixed patterns. These findings have demonstrated that there is a large genetic diversity present in wild collections of M. oleifera collected in Pakistan; whereas low genetic diversity is detected in cultivated accessions obtained from ECHO. Taken together, these results agree with previous reports that M. oleifera is native to the Indo-Pakistan ecological region, and provides sufficient diversity for genetic exploration as well as for genetic improvement efforts.