iTRAQ and RNA-Seq Analyses Provide New Insights into Regulation Mechanism of Symbiotic Germination of Dendrobium officinale Seeds (Orchidaceae).
Mycorrhizal fungi colonize orchid seeds and induce germination. This so-called symbiotic germination is a critical developmental process in the lifecycle of all orchid species. However, the molecular changes that occur during orchid seed symbiotic germination remain largely unknown. To better understand the molecular mechanism of orchid seed germination, we performed a comparative transcriptomic and proteomic analysis of the Chinese traditional medicinal orchid Dendrobium officinale to explore the change in protein expression at the different developmental stages during asymbiotic and symbiotic germination and identify the key proteins that regulate the symbiotic germination of orchid seeds. Among 2256 identified plant proteins, 308 were differentially expressed across three developmental stages during asymbiotic and symbiotic germination, and 229 were differentially expressed during symbiotic germination compared to asymbiotic development. Of these, 32 proteins were coup-regulated at both the proteomic and transcriptomic levels during symbiotic germination compared to asymbiotic germination. Our results suggest that symbiotic germination of D. officinale seeds shares a common signaling pathway with asymbiotic germination during the early germination stage. However, compared to asymbiotic germination, fungal colonization of orchid seeds appears to induce higher and earlier expression of some key proteins involved in lipid and carbohydrate metabolism and thus improves the efficiency of utilization of stored substances present in the embryo. This study provides new insight into the molecular basis of orchid seed germination.
['Chen|Juan|J|0000-0002-5407-8239', 'Liu|Si Si|SS|', 'Kohler|Annegret|A|', 'Yan|Bo|B|', 'Luo|Hong Mei|HM|', 'Chen|Xiao Mei|XM|', 'Guo|Shun Xing|SX|']
D050260:Carbohydrate Metabolism D031667:Dendrobium D018507:Gene Expression Regulation, Developmental D018525:Germination D050356:Lipid Metabolism D038821:Mycorrhizae D010940:Plant Proteins D040901:Proteomics D012639:Seeds D017423:Sequence Analysis, RNA D015398:Signal Transduction D013559:Symbiosis D059467:Transcriptome
Orchidaceae seed germination transcriptome proteome carbohydrate metabolism defense reaction mycorrhizal interaction