Dissecting the genome-wide evolution and functions of NUDX1 in rose monoterpene biosynthesis
Yu Han holds a PhD in Agriculture and works as an associate professor at Beijing Forestry University, Beijing, China. The objective of her studies is to analyze the genetic variation molecular basis and regulation mechanism in rose functional aroma components. Rosa chinensis is the most popular ornamental plant species worldwide. The flowers of this species have diverse colors and fragrances. Geraniol is an acyclic monoterpene compound with a mild, sweet rose fragrance. In rose, the biosynthesis of geraniol is not catalyzed by geraniol synthase, but the nudix hydrolases 1 (NUDX1). A comparative molecular analysis of synteny between species can elucidate the evolutionary trajectory of genes and genomes. Yu applied a phylogenomic synteny network (synnet) of NUDX genes across 115 Rosa and other plant genomes to investigate their origins and evolutionary positions. Combining gene co-expression and other experimental analysis, she predicted the evolutionary trajectory of rose geraniol biosynthesis. Besides geraniol, she also investigated the biosynthesis regulation of other monoterpenes. The acyclic monoterpene β-ocimene has a regulatory effect that can improve plant resistance. It is an important functional aroma component, but its molecular mechanism of biosynthesis is not yet known. She found that the content of β-ocimene in the Rosa hybrid ‘Yellow Island’ was extremely low, but in the bud mutant cultivar ‘Past Feeling’, it was high. At the same time, the expression of RhNUDX1s, which are important to the monoterpene biosynthesis, was significantly up-regulated in the petal of ‘Past Feeling’. Yu used ‘Yellow Island’ and ‘Past Feeling’ as test materials and techniques such as rose callus CRISPR gene editing, rose VIGS gene silencing, and in vitro enzymatic activity verification, to determine the sequence characteristics and gene functions of RhNUDX1s at the DNA, RNA and protein levels. These results will enrich the molecular regulation network of rose monoterpene biosynthesis, and provide references for fragrance molecules to improve rose breeding.
Yu Han won the ISHS Young Minds Award for the best oral presentation at the III International Symposium on Germplasm of Ornamentals in the Republic of Korea in October 2020
A.P. Yu Han, National Engineering Research Center for Floriculture, Beijing Forestry University, No.35 Tsinghua East Road, Haidian District, Beijing, China, e-mail: email@example.com or firstname.lastname@example.org
The article is available in Chronica Horticulturae