Project description:Induced pluripotent stem cells (iPSCs) can provide biological resource for functional and conservation research for various species. However, the understanding of species variations of mammalian iPSCs is still limited. Here, we report the first generation of iPSCs from the endangered species Grevy's zebra (Equus grevyi; gz-iPSCs). We reprogram primary fibroblasts with human reprogramming transcription factors, OCT3/4, SOX2, KLF4, and c-MYC, with the retroviral method and confirmed the pluripotency and differentiation potential. In light of RNA sequencing analysis, generated gz-iPSCs robustly express genes associated with pluripotency and reprogramming processes, including epithelial-to-mesenchymal and mesenchymal-to-epithelial transitions (EMT-MET). Comparative transcriptomics with other species reveals patterns of gene expressions among mammalian PSCs and detects evolutionary conservation of pluripotency-associated genes and plausible importance of translation process. This work will aid in providing biological resource for this endangered species and enables new insight into the evolution of the mammalian PSCs.
Project description:Mycorrhizal fungi colonize orchid seed and induce the germination. This so-called symbiotic germination is a critical developmental process in the lifecycle of all orchids. However, the molecular changes taking place during the orchid seed symbiotic germination still remains largely unknown. To better understand the molecular mechanism of orchid seed germination, we performed comparative transcriptomic and proteomic analysis on Chinese traditional medicinal orchid plants, Dendrobium officinale to explore protein expression change at the different developmental stages between asymbiotic and symbiotic germination and identify the key proteins regulated symbiotic germination of orchid seeds. iTRAQ analysis from 8 samples identified 2256 plant proteins, of which, 308 proteins were differentially expressed across three developmental stages within asymbiotic or symbiotic accession and 229 proteins are differentially expressed in the symbiotic germination compared to asymbiotic germination. 32 proteins are co-upregulated in both proteomic and transcriptomic level for symbiotic germination compared to asymbiotic germination. Our results revealed that symbiotic germination of D. officinale seeds probably shares the common signal pathway with asymbiotic germination during the early germination stage.
Project description:The study of orchid mycorrhizal interactions is particularly complex because of the peculiar life cycle of these plants and their diverse trophic strategies. Here, large-scale transcriptomics has been applied to investigate gene expression in the mycorrhizal roots of the terrestrial mixotrophic orchid Limodorum abortivum under natural conditions. Our results provide new insights into the mechanisms underlying plant-fungus interactions in orchids and in particular on the plant responses to the mycorrhizal symbiont(s) in adult roots. Comparison with gene expression in mycorrhizal roots of another orchid species, Oeceoclades maculata, suggests that amino acids may represent the main nitrogen source in both protocorms and adult orchids, at least for mixotrophic species. The upregulation, in mycorrhizal L. abortivum roots, of some symbiotic molecular marker genes identified in mycorrhizal roots from other orchids as well as in arbuscular mycorrhiza, suggests a common plant core of genes in endomycorrhizal symbioses. Further efforts will be required to understand whether the specificities of orchid mycorrhiza depend on fine-tuned regulation of these common components, or whether specific additional genes are involved.