Project description:Adaptive laboratory evolution is highly effective for improving desired traits through natural selection. However, its applicability is inherently constrained to growth-correlated traits precluding traits of interest that incur a fitness cost, such as metabolite secretion. Here, we introduce the concept of tacking trait enabling natural selection of fitness-costly metabolic traits. The concept is inspired from the tacking maneuver used in sailing for traversing upwind. We use first-principle metabolic models to design an evolution niche wherein the tacking trait and fitness become correlated. Adaptive evolution in this niche, when followed by the reversal to the original niche, manifests in the improvement of the desired trait due to biochemical coupling between the tacking and the desired trait. We experimentally demonstrated this strategy, termed EvolveX, by evolving wine yeasts for increased aroma production. RNA-sequencing was performed for parental and evolved strains in the respective evolution niche and in natural grape must.
Project description:Astragalus polysaccharides (APS), as one of the main effective components of astragalus, have been reported to regulate the processes of inflammation, metabolism, and carcinogenes. We used microarrays to detect the different expression of mRNA in PC3 cells upon APS treatment.
Project description:To identify biomarkers regulated by traditional Chinese medicine Astragalus membranaceus Fischer Bge. var. mongolicus Bge. Hsiao in colorectal cancer. We have identified several differentially expressed genes including microRNAs using Affymetrix HTA-2.0 array. In this dataset, we include the expression data obtained from colon cancer cell line HCT116 grafted into nude mice. The mice was treated either water or traditional Chinese medicine Astragalus membranaceus for 28 days. These data are used to obtain 1425 genes that are differentially expressed in response to Astragalus membranaceus treatment.
Project description:Adaptive laboratory evolution is highly effective for improving desired traits through natural selection. However, its applicability is inherently constrained to growth-correlated traits precluding traits of interest that incur a fitness cost, such as metabolite secretion. Here, we introduce the concept of tacking trait enabling natural selection of fitness-costly metabolic traits. The concept is inspired from the tacking maneuver used in sailing for traversing upwind. We use first-principle metabolic models to design an evolution niche wherein the tacking trait and fitness become correlated. Adaptive evolution in this niche, when followed by the reversal to the original niche, manifests in the improvement of the desired trait due to biochemical coupling between the tacking and the desired trait. We experimentally demonstrate this strategy, termed EvolveX, by evolving wine yeasts for increased aroma production. Our results pave the way for precision laboratory evolution for biotechnological and ecological applications.
Project description:Transposable elements profoundly affect the biology and evolution of their hosts, yet their own evolutionary dynamics remain poorly understood. Here, we investigate insect endogenous retroviruses (iERVs), a monophyletic group of LTR retrotransposons that have acquired the trait of infectivity, likely through capture of a Baculovirus envelope gene. In Drosophila ovaries, iERVs with functional envelope have adapted their cis-regulatory sequences to be expressed in any somatic cell type, from where they infect the germline. Strikingly, related retroviruses show distinct expression patterns, indicating niche partitioning. In contrast, all non-infectious iERVs that emerged through secondary envelope-loss are specifically expressed in the germline. Co-evolving with iERVs, the genome-protecting piRNA pathway has assimilated iERV promoter and sequence information into piRNA clusters, underscoring the functional significance of iERV expression in somatic niches. We propose that the evolutionary innovation of cell-to-cell infectivity has triggered the adaptive radiation of iERVs through trait diversification and antagonistic virus-host interactions, processes that likely underpin niche-specific expression of endogenous retroviruses in vertebrates as well.
Project description:We describe Ribo Mega-SEC, a powerful approach for the separation and biochemical analysis of mammalian polysomes and ribosomal subunits using Size Exclusion Chromatography and uHPLC, which was achieved within 15 min from sample injection to fraction collection. Ribo Mega-SEC reproducibly shows translating ribosomes exist predominantly in polysome complexes in extracts isolated from human cell lines and mouse liver tissue, which alter in response to starvation. Ribo Mega-SEC provides a rapid, efficient, convenient and highly reproducible method for studying functional translation complexes and is easily combined with high-through put analysis such as proteomics and RNA-Seq, or with structural analysis using electron microscopy. We propose that Ribo Mega-SEC analysis is an accessible alternative to traditional polysome profiling using sucrose density gradients.