Deyu Xie

Borlaug Fellowship Program for Sri Lanka fellow to spend 12 weeks at NC State conducting research to identify and characterize candidate resistance genes against blister blight disease in teac (Chinese sinensis).

Borlaug Fellowship Program for Turkey fellow to spend 12 weeks at NC State conducting research to weaken wheat phenylalanine ammonia-lyase gene promotor by homology directed repaid CRISPR-Cas9 technology to obtain more economical and effective biofuel production.

The fellow will work on a topic entitled “Metabolomics of cacao” under the mentoring of Dr. Deyu Xie. Through this project, the fellow will learn extraction approaches of metabolites from cacao nuts and chocolate, HPLC-qTOF-MS/MS based metabolomics, structural annotation of metabolites, principal component analysis, and heatmap and hierarchy clustering analysis. The fellow will be instructed to read important literatures to understand the principle of metabolomics. In addition, the fellow will attend Xie’s weekly lab meeting and departmental seminars to gain additional opportunities to learn research progresses in other topics. By the end of this program, the fellow will master main metabolomics-based technology for characterization of functional metabolites in cacao nuts and will be able to develop research projects at their home university.

1. Understanding downregulation mechanisms of tobacco alkaloid biosynthesis by PAP1 Specific goals include: • 1-1: Transcriptional analysis of known genes involved in tobacco alkaloid biosynthesis • 1-2: PAP1 interaction with promoters of down-regulated pathway genes • 1-3: PAP1 interaction with NtMYC2a, b, c • 1-4: Transcriptomics of red versus vector control transgenic plants as well as wild-type plants • 1-5: PAP1 or PAP1 complex-based biotechnology for reduction of nicotine, nornicotine and TSNA 2. Screening of anthocyanin-pigmentation from fast neutron deletion mutagenesis of K326 and Dark tobacco for red tobacco varieties

Variation in floral display (inflorescence) affects the success of plant reproduction and the yield of a crop by influencing seed number and dispersal/harvest ability. Despite its importance, little progress has been made in understanding how developmental and genetic changes have shaped inflorescence architectures in angiosperm evolution, in part because existing model organisms exhibit little variation in these traits. Species of Dogwood (Cornus L.) are popular ornamental trees in American landscapes due to their spectacular inflorescences often associated with large showy (petaloid) bracts. The genus offers us a unique opportunity to tackle this important problem. Cornus exhibits a wide variation in inflorescence structure, including heads, umbels and compound cymes. A recent breakthrough in our laboratory has resulted in successful regeneration and transformation of a key species of the genus. This new ability along with our recent achievements in phylogenetic reconstruction and nearly completed comparative developmental studies, now provides a timely opportunity to develop a model for investigating the molecular mechanisms shaping inflorescence architectures in a non-model plant lineage. In this proposal, we aim to test four hypotheses to gain insights into the changes in developmental and genetic mechanisms that may have led to alteration of inflorescence forms in dogwoods. Hypotheses: 1. Differences in early development processes lay the ground for divergence of inflorescence architectures in dogwood species. 2. Spatial, temporal, and quantitative variation of expression of conserved key inflorescence regulatory genes are essential for the changes of inflorescence architecture. 3. Expression of petal identity genes in bracts is essential for the origin of the petaloidy of bracts in dogwoods. 4. Spatial, temporal, and quantitative variation of expression of other genes are essential for the modification of inflorescence architecture and origin of petaloid bracts in dogwoods. Objectives: 1. Complete the comparative developmental characterization of four Cornus inflorescence types. 2. Comparative characterization of the expression of conserved key inflorescence regulators and petal identity genes in different inflorescence types. 3. Identify new genes regulating inflorescence development and bract petaloidy in dogwood. 4. Optimize the existing transformation system of Cornus canadensis and test the function of conserved key inflorescence regulatory genes Intellectual merits: This project represents the first study investigating the molecular controls of inflorescence development and evolution using a comparative approach on multiple closely related woody species from a non-model plant lineage. Although the proposal has technical challenges, we have overcome the most significant hurdles and achieving of our objectives would offer novel insights into the genetic basis underlying the evolutionary transitions of floral display strategies, of which the knowledge is presently lacking. The transformation system has tremendous potentials for future research of genetic controls of other plant traits including resistance to fungal diseases and drought, and flowering time divergence among species. By providing a transformation system in a non-model plant, this study will potentially provide a new tool for genetic analysis in other plants that are more closely related to the dogwoods than to the few existing model species. Broader impact: The project will not only enhance our understanding of inflorescence development and evolution in angiosperms, but also hold promise in breeding and bioengineering of dogwoods. Biotechnological improvement of Cornus species in display, disease and drought resistance holds tremendous industrial potential. Thus the results of this project will have broad interests to the scientific, biotechnolgical, and industrial communities. Perfection of the transformation system will immediately benefit the research of identifying genes resistant to the dogwood anthracnose disease that