title: Profiling gene expression in citrus fruit calyx abscission zone (AZ-C) treated with ethylene.
abstract: On-tree storage and harvesting of mature fruit account for a large proportion of cost in the production of citrus, and a reduction of the cost would not be achieved without a thorough understanding of the mechani sm of the mature fruit abscission. Genome-wide gene expression changes in ethylene-treated fruit calyx abscission zone (AZ-C) of Citrus sinensis cv. Olinda were therefore investigated using a citrus genome array representing up to 33,879 citrus transcripts. In total, 1313 and 1044 differentially regulated genes were identified in AZ-C treated with ethylene for 4 and 24 h, respectively. The results showed that mature citrus fruit abscission commenced with the activation of ethylene signal transduction pathway that led to the activation of ethylene responsive transcription factors and the subsequent transcriptional regulation of a large set of ethylene responsive genes. Significantly down-regulated genes included those of starch/sugar biosynthesis, transportation of water and growth promoting hormone synthesis and signaling, whereas significantly up-regulated genes were those involved in defense, cell wall degradation, and secondary metabolism. Our data unraveled the underlying mechanisms of some known important biochemical events occurring at AZ-C and should provide informative suggestions for future manipulation of the events to achieve a controllable abscission for mature citrus fruit.
authors.affiliation: Institute of Fruit Tree Research, Guangdong Academy of Agricultural Sciences Guangzhou, Guangdong, 510640, People's Republic of China. ld0532cheng@126.com.|College of Horticulture and Landscape Architecture, Southwest University, Beibei, Chongqing, 400715, People's Republic of China. ld0532cheng@126.com.|Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization Ministry of Agriculture Guangzhou, Guangdong, 510640, People's Republic of China. ld0532cheng@126.com.|Key Laboratory of Tropical and Subtropical Fruit tree Researches, Guangdong Province Guangzhou, Guangdong, 510640, People's Republic of China. ld0532cheng@126.com.
authors.forename: Chunzhen
authors.initials: C
authors.lastname: Cheng
authors.affiliation: School of Geographic and Environmental Sciences, Guizhou Normal University Guizhou, Guiyang, 550001, People's Republic of China.
authors.forename: Lingyun
authors.initials: L
authors.lastname: Zhang
authors.affiliation: College of Agriculture, Guizhou University Guiyang, Guizhou, 550025, People's Republic of China.
authors.forename: Xuelian
authors.initials: X
authors.lastname: Yang
authors.affiliation: Institute of Fruit Tree Research, Guangdong Academy of Agricultural Sciences Guangzhou, Guangdong, 510640, People's Republic of China. gy_zhong@163.com.|Key Laboratory of South Subtropical Fruit Biology and Genetic Resource Utilization Ministry of Agriculture Guangzhou, Guangdong, 510640, People's Republic of China. gy_zhong@163.com.|Key Laboratory of Tropical and Subtropical Fruit tree Researches, Guangdong Province Guangzhou, Guangdong, 510640, People's Republic of China. gy_zhong@163.com.
authors.forename: Guangyan
authors.initials: G
authors.lastname: Zhong
mesh_terms: D002957:Citrus / Q000235:genetics*; D004579:Electron Transport; D005030:Ethylenes / Q000008:administration & dosage*; D035264:Flowers / Q000235:genetics*; D020869:Gene Expression Profiling; D017343:Genes, Plant; D008928:Mitochondria / Q000378:metabolism; D010788:Photosynthesis; D010937:Plant Growth Regulators / Q000378:metabolism
chemical_list: D005030:Ethylenes; D010937:Plant Growth Regulators; C036216:ethylene
keywords: Abscission; Calyx abscission zone (AZ-C); Ethylene; Mature citrus fruit; Microarray