Project description:The desert plant Populus euphratica Oliv. has typical heterophylly; linear (Li), lanceolate (La), ovate (Ov) and broad-ovate (Bo) leaves grow in turn from young to adult trees. It is therefore a potential model organism for leaf development. To investigate the roles of RNAs (including mRNAs, miRNAs, lncRNAs and circRNAs) in the morphogenesis of P. euphratica heterophyll, the juvenile heterophyll were respectively sampled, and then their expression patterns were analyzed by small RNA sequencing and strand-specific RNA sequencing. We found that 1374 mRNAs, 19 miRNAs, 71 lncRNAs and 2 circRNAs were P. euphratica heterophyll morphogenesis associated (PHMA) RNAs, among them, 17 PHMA miRNAs could disturb the expression of 46 PHMA mRNAs, furthermore, 11 lncRNAs and 2 circRNAs interacted with 27 PHMA mRNAs by ceRNA hypothesis, respectively. According to GO and KEGG pathway analysis, PHMA RNAs were mainly involved in metabolic, response to stimulus and developmental processes. Our results indicated that both external environmental factors and genetic factors of P. euphratica co-regulated the expression of PHMA RNAs, caused the cell division was repressed, while cell growth was reinforced, and resulted in the morphogenesis of P. euphratica heterophyll, ultimately.
Project description:We present an efficient method to genome-wide discover new and drought stress responsive miRNAs in P. euphratica. High throughput sequencing of P. euphratica leaves found 197 conserved miRNAs between P. euphratica and Populus trichocarpa. Meanwhile, 189 new miRNAs which belonged to 120 families were identified, a large increasing to the number of P. euphratica miRNAs. Target prediction and degradome sequencing verification of 22 new and 21 conserved miRNA targets showed these targets were involved in multiple biological processes, including transcription regulation and response to stimulus. Furthermore, comparison of high-throughput sequencing with miRNA microarray profiling data indicated that 104 miRNA sequences were up-regulated, while 27 were down-regulated under drought stress. This preliminary characterization based on our findings provided a framework for future analysis of miRNA genes and their roles in key traits of poplar as stress resistance plant breeding and environment protection usage.