title: Cloning the tomato curl3 gene highlights the putative dual role of the leucine-rich repeat receptor kinase tBRI1/SR160 in plant steroid hormone and peptide hormone signaling.
abstract: Brassinosteroids (BRs) are plant steroid hormones that are essential for normal plant development. To gain better understanding of the conservation of BR signaling, the partially BR-insensitive tomato mutant altered brassinolide sensitivity1 (abs1) was identified and found to be a weak allele at the curl3 (cu3) locus. BR content is increased in both of these mutants and is associated with increased expression of DWARF: The tomato homolog of the Arabidopsis Brassinosteroid Insensitive1 Leu-rich repeat (LRR) receptor-like kinase, named tBri1, was isolated using degenerate primers. Sequence analysis of tBRI1 in the mutants cu3 and abs1 revealed that cu3 is a nonsense mutant and that abs1 is a missense mutant. A comparison of BRI1 homolog sequences highlights conserved features of BRI1 sequences, with the LRRs in close proximity to the island domain showing more conservation than N-terminal LRRs. The most homologous sequences were found in the kinase and transmembrane regions. tBRI1 (SR160) also has been isolated as the putative receptor for systemin, a plant peptide hormone. This finding suggests a possible dual role for tBRI1 in steroid hormone and peptide hormone signaling.
authors.affiliation: Institute of Biological Sciences, University of Wales Aberystwyth, Aberystwyth SY23 3DA, United Kingdom.
authors.forename: Teresa
authors.initials: T
authors.lastname: Montoya
authors.forename: Takahito
authors.initials: T
authors.lastname: Nomura
authors.forename: Kerrie
authors.initials: K
authors.lastname: Farrar
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Kaneta
authors.forename: Takao
authors.initials: T
authors.lastname: Yokota
authors.forename: Gerard J
authors.initials: GJ
authors.lastname: Bishop
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D029681:Arabidopsis Proteins; D060406:Brassinosteroids; D002777:Cholestanols / Q000378:metabolism; D003001:Cloning, Molecular; D018389:Codon, Nonsense; D018551:Solanum lycopersicum / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D020125:Mutation, Missense; D010455:Peptides / Q000378:metabolism; D010641:Phenotype; D010840:Phytosterols / Q000378:metabolism; D010937:Plant Growth Regulators / Q000494:pharmacology*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D011494:Protein Kinases / Q000235:genetics* / Q000378:metabolism; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism; D020449:Repetitive Sequences, Amino Acid / Q000235:genetics / Q000502:physiology; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics* / Q000502:physiology; D013260:Steroids, Heterocyclic / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D060406:Brassinosteroids; D002777:Cholestanols; D018389:Codon, Nonsense; D010455:Peptides; D010840:Phytosterols; D010937:Plant Growth Regulators; D010940:Plant Proteins; D013260:Steroids, Heterocyclic; C073704:systemin; D011494:Protein Kinases; D020794:Receptor Protein-Tyrosine Kinases; C108270:BRI1 protein, Arabidopsis; C023623:brassinolide