%0 Journal Article
%T Generation and Analysis of Expressed Sequence Tags from Chimonanthus praecox (Wintersweet) Flowers for Discovering Stress-Responsive and Floral Development-Related Genes
%A Shunzhao Sui
%A Jianghui Luo
%A Jing Ma
%A Qinlong Zhu
%A Xinghua Lei
%A Mingyang Li
%J International Journal of Genomics
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/134596
%X A complementary DNA library was constructed from the flowers of Chimonanthus praecox, an ornamental perennial shrub blossoming in winter in China. Eight hundred sixty-seven high-quality expressed sequence tag sequences with an average read length of 673.8£¿bp were acquired. A nonredundant set of 479 unigenes, including 94 contigs and 385 singletons, was identified after the expressed sequence tags were clustered and assembled. BLAST analysis against the nonredundant protein database and nonredundant nucleotide database revealed that 405 unigenes shared significant homology with known genes. The homologous unigenes were categorized according to Gene Ontology hierarchies (biological, cellular, and molecular). By BLAST analysis and Gene Ontology annotation, 95 unigenes involved in stress and defense and 19 unigenes related to floral development were identified based on existing knowledge. Twelve genes, of which 9 were annotated as ¡°cold response,¡± were examined by real-time RT-PCR to understand the changes in expression patterns under cold stress and to validate the findings. Fourteen genes, including 11 genes related to floral development, were also detected by real-time RT-PCR to validate the expression patterns in the blooming process and in different tissues. This study provides a useful basis for the genomic analysis of C. praecox. 1. Introduction Chimonanthus praecox (L.) Link, wintersweet, belongs to the Calycanthaceae family. It is a perennial deciduous shrub and blossoms in winter, from late November to March. Its unique flowering time and long blooming period make it one of most popular ornamental plants in China [1]. C. praecox is mainly a garden plant that also provides cut flowers. The flower is strongly fragrant and may be used as a source of essential oil, which has received much attention in New Zealand [2]. C. praecox thrives in cold environments and blooms in low-temperature seasons with little rainfall. The plant is assumed to be rich in genes related to floral development and adversities, especially those responding to environmental stress factors. However, the molecular mechanism that regulates floral development and copes with stresses in C. praecox flowers remains unclear. Expressed sequence tags (ESTs) have been proven to be an efficient and rapid means to identify novel genes (and proteins) induced by environmental changes or stresses [3¨C7]. Genes related to flower form, longevity, and scent from roses, Phalaenopsis equestris, and Pandanus fascicularis were identified by ESTs [8¨C10]. The present study used transcriptomic analysis of
%U http://www.hindawi.com/journals/ijg/2012/134596/