title: Identification and transcript profiles of citrus growth-regulating factor genes involved in the regulation of leaf and fruit development.
abstract: Growth-regulating factor (GRF) is an important protein in GA-mediated response, with key roles in plant growth and development. However, it is not known whether or how the GRF proteins in citrus to regulate organ size. In this study, nine citrus GRF genes (CsGRF1-9) were validated from the 'Anliu' sweet orange (AL, Citrus sinensis cv. Anliu) by PCR amplification. They all contain two conserved motifs (QLQ and WRC) and have 3-4 exons. The transcript levels of genes were detected by qRT-PCR. Transcript analysis showed that (1) CsGRF 1, 2, 5, 6, 7, and 9 expressed predominantly in young leaf, CsGRF 3 and 4 expressed predominantly in fruit immature juice sacs and CsGRF 8 expressed predominantly in root; (2) all citrus GRF genes had significantly higher expression in young leaves than mature leaf; (3) in juice sacs, the transcript levels of CsGRF1, 4, 5, 6, and 8 increased significantly while the transcript levels of CsGRF2, 3, 7, and 9 had no significant change from 80 DAF to 100 DAF. Besides, GA3 treatment did not affect the transcript levels of CsGRF5 and CsGRF6 but significantly increased the transcript levels of the other seven CsGRF genes in young leaves. These results suggested that all CsGRF genes involve in the leaf development, CsGRF1, 4, 5, 6, and 8 act developmentally whilst CsGRF2, 3, 7, and 9 play fundamental roles in fruit cell enlargement, which may be through GA pathway or GA-independent pathway.
authors: Key Laboratory of Horticultural Plant Biology (Huazhong Agricultural University), Ministry of Education, Wuhan, 430070, People's Republic of China.
authors: Xiao
authors: X
authors: Liu
authors: Key Laboratory of Horticultural Plant Biology (Huazhong Agricultural University), Ministry of Education, Wuhan, 430070, People's Republic of China.
authors: Ling-Xia
authors: LX
authors: Guo
authors: Key Laboratory of Horticultural Plant Biology (Huazhong Agricultural University), Ministry of Education, Wuhan, 430070, People's Republic of China.
authors: Long-Fei
authors: LF
authors: Jin
authors: Key Laboratory of Horticultural Plant Biology (Huazhong Agricultural University), Ministry of Education, Wuhan, 430070, People's Republic of China. liuyongzhong@mail.hzau.edu.cn.|Key Laboratory of Horticultural Crop Biology and Genetic Improvement (Central Region), Ministry of Education, Wuhan, 430070, People's Republic of China. liuyongzhong@mail.hzau.edu.cn.
authors: Yong-Zhong
authors: http://orcid.org/0000-0002-1071-490X
authors: YZ
authors: Liu
authors: Key Laboratory of Horticultural Plant Biology (Huazhong Agricultural University), Ministry of Education, Wuhan, 430070, People's Republic of China.
authors: Tao
authors: T
authors: Liu
authors: Key Laboratory of Horticultural Plant Biology (Huazhong Agricultural University), Ministry of Education, Wuhan, 430070, People's Republic of China.
authors: Yu-Hua
authors: YH
authors: Fan
authors: Key Laboratory of Horticultural Plant Biology (Huazhong Agricultural University), Ministry of Education, Wuhan, 430070, People's Republic of China.
authors: Shu-Ang
authors: SA
authors: Peng
mesh_terms: D002957:Citrus / Q000187:drug effects / Q000235:genetics* / Q000254:growth & development; D005638:Fruit / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D020869:Gene Expression Profiling / Q000379:methods; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D005875:Gibberellins / Q000494:pharmacology; D010802:Phylogeny; D018515:Plant Leaves / Q000187:drug effects / Q000235:genetics / Q000254:growth & development*; D010940:Plant Proteins / Q000235:genetics; D014018:Tissue Distribution; D014157:Transcription Factors / Q000235:genetics*
chemical_list: D005875:Gibberellins; D010940:Plant Proteins; D014157:Transcription Factors; C007842:gibberellic acid
keywords: Citrus; Fruit development; GA3; GRF