Project description:MicroRNAs (miRNAs) are essential small RNA molecules that regulate the expression of target mRNAs in plants and animals. Here, we aimed to identify miRNAs and their putative targets in Hibiscus syriacus, the national flower of South Korea. Therefore, we employed high-throughput sequencing of small RNAs obtained from four different tissues (i.e., leaf, root, flower, and ovary) and identified 33 conserved and 30 novel miRNA families, many of which showed differential tissue-specific expressions. In addition, we computationally predicted novel targets of miRNAs and validated some of them using 5′ rapid amplification of cDNA ends analysis. One of the validated novel targets of miR477 was a terpene synthase, the primary gene involved in the formation of disease-resistant terpene metabolites such as sterols and phytoalexins. In addition, a predicted target of conserved miRNAs, miR396, is SHORT VEGETATIVE PHASE, which is involved in flower initiation and is duplicated in Hibiscus syriacus. Collectively, this study provides the first reliable draft of the Hibiscus syriacus miRNA transcriptome that should constitute a basis for understanding the biological roles of miRNAs in Hibiscus syriacus.
Project description:Higher aridity and more extreme rainfall events in drylands are predicted under climate change. Yet it is unclear how changing precipitation regimes may affect nitrogen (N) cycling, especially in areas with extremely high aridity. Here we investigated soil N isotopic values (M-NM-415N) along a 3200 km aridity gradient and show a hump-shaped relationship between soil M-NM-415N and aridity index (AI) with a threshold at AI=0.32. Also, using a micro-array metageomics tool named GeoChip 5.0, we showed that Variations of nitrification and denitrification gene abundance along the gradient which provide further evidence for the existence of this threshold. Data support the hypothesis that the increase of gaseous N losses is higher than the increase of net plant N accumulation with increasing AI below AI=0.32, while the opposite is favoured above this threshold. Our results suggest the importance of N-cycling microbes in extremely dry areas and the different controlling factors of N cycling on the either side of the threshold.
Project description:Common transcriptional responses of Arabidopsis thaliana protoplasts transfected with turnip crinkle virus (TCV) , hibiscus chlorotic ringspot virus (HCRSV) and their coat protein mutants.
Project description:Elucidating the genetic control of development of C3 and C4 photosynthesis. Atriplex rosea (C4) and Atriplex prostrata (C3) were studied along a leaf developmental gradient to compare development between C3 and C4. C3 Atriplex prostrata x C4 Atriplex rosea F1 hybrid were studied along the same developmental gradient and will aid in identifying regulatory elements involved in C3 and C4 leaf development.
