title: GbTCP, a cotton TCP transcription factor, confers fibre elongation and root hair development by a complex regulating system.
abstract: As the most important natural raw material for textile industry, cotton fibres are an excellent model for studying single-cell development. Although expression profiling and functional genomics have provided some data, the mechanism of fibre development is still not well known. A class I TCP transcription factor (designated GbTCP), encoding 344 amino acids, was isolated from the normalized cDNA library of sea-island cotton fibre (from -2 to 25 days post anthesis). GbTCP was preferentially expressed in the elongating cotton fibre from 5 to 15 days post anthesis. Some expression was also observed in stems, apical buds, and petals. RNAi silencing of GbTCP produced shorter fibre, a reduced lint percentage, and a lower fibre quality than the wild-type plants. Overexpression of GbTCP enhanced root hair initiation and elongation in Arabidopsis and regulated branching. Solexa sequencing and Affymetrix GeneChip analysis indicated that GbTCP positively regulates the level of jasmonic acid (JA) and, as a result, activates downstream genes (reactive oxygen species, calcium signalling, ethylene biosynthesis and response, and several NAC and WRKY transcription factors) necessary for elongation of fibres and root hairs. JA content analysis in cotton also  confirmed that GbTCP has a profound effect on JA biosynthesis. In vitro ovule culture showed that an appropriate concentration of JA promoted fibre elongation. The results suggest that GbTCP is an important transcription factor for fibre and root hair development by regulating JA biosynthesis and response and other pathways, including reactive oxygen species, calcium channel and ethylene signalling.
authors.affiliation: National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan, Hubei 430070,  PR China.
authors.forename: Juan
authors.initials: J
authors.lastname: Hao
authors.forename: Lili
authors.initials: L
authors.lastname: Tu
authors.forename: Haiyan
authors.initials: H
authors.lastname: Hu
authors.forename: Jiafu
authors.initials: J
authors.lastname: Tan
authors.forename: Fenglin
authors.initials: F
authors.lastname: Deng
authors.forename: Wenxin
authors.initials: W
authors.lastname: Tang
authors.forename: Yichun
authors.initials: Y
authors.lastname: Nie
authors.forename: Xianlong
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D001483:Base Sequence; D032561:Cotton Fiber; D003517:Cyclopentanes / Q000032:analysis / Q000378:metabolism*; D035264:Flowers / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D003368:Gossypium / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D059014:High-Throughput Nucleotide Sequencing; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis; D054883:Oxylipins / Q000032:analysis / Q000378:metabolism*; D010802:Phylogeny; D010937:Plant Growth Regulators / Q000032:analysis / Q000378:metabolism*; D018515:Plant Leaves / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D018517:Plant Roots / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D030821:Plants, Genetically Modified; D011401:Promoter Regions, Genetic / Q000235:genetics; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D003517:Cyclopentanes; D054883:Oxylipins; D010937:Plant Growth Regulators; D010940:Plant Proteins; D014157:Transcription Factors; C011006:jasmonic acid