Project description:Carotenoids have been demonstrated to be indispensable plant secondary metabolites that are involved in photosynthesis, antioxidation, and phytohormone biosynthesis. Carotenoids are likely involved in other biological functions that have yet to be discovered. In this study, we utilized genomic expression investigation to gain a deep insight into the carotenoid-related biological processes in the citrus calli overexpressing CrtB. Abortive ovule embryogenic calli from four citrus genotypes were used in this study. They were derived from Star Ruby grapefruit (C. paradise Macf.), Marsh grapefruit (C. paradise Macf.), and Sunburst mandarin [Citrus reticulata Blanco M-CM-^W (C. paradisi Macf. M-CM-^W C. reticulata)], designated as RB, M, and SBT, respectively. Engineered cell models (ECMs) were established by over-expressing 35S::CrtB (tpM-bM-^@M-^SrbcSM-bM-^@M-^SCrtB) [CrtB protein, phytoene synthase from Erwinia herbicola (now known as Pantoea agglomerans), containing a Pea rbcS transit peptide] in citrus embryogenic calli. Twenty-day-old calli were harvested and used for RNA extraction and hybridization on Affymetrix microarrays.
Project description:Finding the differences in gene expression in three regions of the brai, basal ganglia, white matter, and frontal cortex, in normal, HIV infected, HIV inefected with neurocognitive impairment, and HIV infected with both neurocognitive impairment and encephalitis patients. We used microarrays to identify differentially expressed genes in normal, HIV infected, HIV inefected with neurocognitive impairment, and HIV infected with both neurocognitive impairment and encephalitis patients. Samples from three different brain regions from normal, HIV infected, HIV infected with neurocognitive impairment (HAD: HIV-associated dementia), and HIV infected with both neurocognitive impairment and encephalitis (HIVE: HIV encephalitis) patients were collected for RNA isolation and supsequent Affymetrix microarray analysis. We sought to obtain gene expression levels in different brain regions to find implication of HIV and the neurological impairment and inflammation associated with HIV infection.
Project description:Birds and other reptiles possess a diversity of feather and scale-like skin appendages. Feathers are commonly assumed to have originated from ancestral scales in theropod dinosaurs. However, most birds also have scaled feet, indicating birds evolved the capacity to grow both ancestral and derived morphologies. This suggests a more complex evolutionary history than a simple linear transition between feathers and scales. We set out to investigate the evolution of feathers via the comparison of transcriptomes assembled from diverse skin appendages in chicken, emu, and alligator. Our data reveal that feathers and the overlapping ‘scutate’ scales of birds share more similar gene expression to each other, and to two types of alligator scales, than they do to the tuberculate ‘reticulate’ scales on bird footpads. Accordingly, we propose a history of skin appendage diversification, in which feathers and bird scutate scales arose from ancestral archosaur body scales, whereas reticulate scales arose earlier in tetrapod evolution. We also show that many “feather-specific genes” are also expressed in alligator scales. In-situ hybridization results in feather buds suggest that these genes represent ancestral scale genes that acquired novel roles in feather morphogenesis and were repressed in bird scales. Our findings suggest that the differential reuse, in feathers, and suppression, in bird scales, of genes ancestrally expressed in archosaur scales has been a key factor in the origin of feathers – and may represent an important mechanism for the origin of evolutionary novelties.