title: Overexpression of an F-box protein gene disrupts cotyledon vein patterning in Arabidopsis.
abstract: Plant vascular patterning is complex. However, the detailed molecular mechanism of vascular patterning is still unknown. In this study, FBXL, an Arabidopsis F-box motif gene, was isolated by using 3' rapid amplification of cDNA ends (RACE) technique. The gene contained a coding sequence of 1407 nucleotides coding 468 amino acid residues. Amino acid sequence analysis revealed that the gene encoded a protein harboring an F-box motif at the N terminus, an LRRs motif in the middle, and an FBD motif at the C terminus. FBXL promoter-β-glucuronidase (GUS) and 35S promoter-FBXL vectors were constructed and transformed into Arabidopsis thaliana to understand the function of the FBXL gene. GUS expression analysis indicated that FBXL was specifically expressed in the vascular tissues of the root, stem, leaf, and inflorescence. FBXL overexpression in Arabidopsis displayed an abnormal venation pattern in cotyledons. Furthermore, FBXL expression was not induced by exogenous auxin and its transcript accumulation did not overlap with the distribution of endogenous auxin. These results suggested that FBXL may be involved in cotyledon vein patterning via auxin-independent pathway.
authors.affiliation: Department of Molecular and Cell Biology, School of Life Science and Technology, Tongji University, Shanghai, 200092, China.
authors.forename: Xianghuan
authors.initials: X
authors.lastname: Cui
authors.affiliation: Department of Molecular and Cell Biology, School of Life Science and Technology, Tongji University, Shanghai, 200092, China.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Xu
authors.affiliation: Department of Molecular and Cell Biology, School of Life Science and Technology, Tongji University, Shanghai, 200092, China.
authors.forename: Yangyang
authors.initials: Y
authors.lastname: He
authors.affiliation: Department of Molecular and Cell Biology, School of Life Science and Technology, Tongji University, Shanghai, 200092, China.
authors.forename: Xiling
authors.initials: X
authors.lastname: Du
authors.affiliation: Department of Molecular and Cell Biology, School of Life Science and Technology, Tongji University, Shanghai, 200092, China. Electronic address: zhujian1@tongji.edu.cn.
authors.forename: Jian
authors.initials: J
authors.lastname: Zhu
mesh_terms: D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000096:biosynthesis* / Q000235:genetics; D018548:Cotyledon / Q000235:genetics / Q000378:metabolism*; D044783:F-Box Proteins / Q000096:biosynthesis* / Q000235:genetics; D015870:Gene Expression; D058526:Plant Vascular Bundle / Q000235:genetics / Q000378:metabolism*; D011401:Promoter Regions, Genetic
chemical_list: D029681:Arabidopsis Proteins; D044783:F-Box Proteins
keywords: Arabidopsis thaliana; Cotyledon vein patterning; F-box domain proteins; FBXL