title: Identification of OsbHLH133 as a regulator of iron distribution between roots and shoots in Oryza sativa.
abstract: Iron (Fe) is an essential micronutrient element for plant growth. Regulation of Fe-deficiency signalling networks is one of the many functions reported for basic helix-loop-helix (bHLH) transcription factors in plants. In the present study, OsbHLH133 was found to be induced by Fe-deficiency conditions in Oryza sativa. Insertional inactivation of OsbHLH133 (bhlh133) resulted in growth retardation, with enhanced Fe concentration seen in shoots, and reduced Fe concentration in roots. Overexpression of OsbHLH133 had the opposite effect, that is resulted in an enhanced Fe concentration in roots and reduced Fe concentration in shoots and also in xylem sap. Microarray analysis showed that some of the genes encoding Fe-related functions were up-regulated under Fe-sufficient conditions, in bhlh133 mutant plants compared to wild-type plants. Significant differential expression of a number of signalling pathways, including calcium signalling, was also seen in bhlh133 plants compared to wild-type plants, independent of Fe conditions.
authors: State Key Laboratory of Plant Physiology and Biochemistry Joint Research Laboratory in Genomics and Nutriomics, College of Life Sciences, Zhejiang University, Hangzhou, China.
authors: Lu
authors: L
authors: Wang
authors: Yinghui
authors: Y
authors: Ying
authors: Reena
authors: R
authors: Narsai
authors: Lingxiao
authors: L
authors: Ye
authors: Luqing
authors: L
authors: Zheng
authors: Jingluan
authors: J
authors: Tian
authors: James
authors: J
authors: Whelan
authors: Huixia
authors: H
authors: Shou
mesh_terms: D051792:Basic Helix-Loop-Helix Proteins / Q000378:metabolism*; D004269:DNA, Bacterial; D018506:Gene Expression Regulation, Plant; D007501:Iron / Q000378:metabolism*; D016254:Mutagenesis, Insertional; D020411:Oligonucleotide Array Sequence Analysis; D012275:Oryza / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism*; D018517:Plant Roots / Q000378:metabolism; D018520:Plant Shoots / Q000378:metabolism; D015854:Up-Regulation
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D004269:DNA, Bacterial; D007501:Iron; D010940:Plant Proteins; C036483:T-DNA