BAK1 is involved in AtRALF1-induced inhibition of root cell expansion

Autor(es)

Dressano, Keini ^[1] ; Ceciliato, Paulo H. O. ^[1] ; Silva, Aparecida L. ^[1] ; Guerrero-Abad, Juan Carlos ^[1] ; Bergonci, Tabata ^[1] ; Ortiz-Morea, Fausto Andres ^[1] ; Buerger, Marco ^[2] ; Silva-Filho, Marcio C. ^[3] ; Moura, Daniel S. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo ESALQ USP, Escola Super Agr Luiz de Queiroz, Dept Ciencias Biol, Lab Bioquim Prot, Piracicaba, SP - Brazil

^[2] Salk Inst Biol Studies, Plant Biol Lab, La Jolla, CA 92037 - USA

^[3] Univ Sao Paulo ESALQ USP, Escola Super Agr Luiz de Queiroz, Dept Genet, Lab Biol Mol Plantas, Piracicaba, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: PLOS GENETICS; v. 13, n. 10 OCT 2017.
• Citações Web of Science: 9

Resumo

The rapid alkalinization factor (RALF) peptide negatively regulates cell expansion, and an antagonistic relationship has been demonstrated between AtRALF1, a root-specific RALF isoform in Arabidopsis, and brassinosteroids (BRs). An evaluation of the response of BR signaling mutants to AtRALF1 revealed that BRI1-associated receptor kinase1 (bak1) mutants are insensitive to AtRALF1 root growth inhibition activity. BAK1 was essential for the induction of AtRALF1-responsive genes but showed no effect on the mobilization of Ca2+ and alkalinization responses. Homozygous plants accumulating AtRALF1 and lacking the BAK1 gene did not exhibit the characteristic semi-dwarf phenotype of AtRALF1-overexpressors. Biochemical evidence indicates that AtRALF1 and BAK1 physically interact with a K-d of 4.6 mu M and acridinium-labeled AtRALF1 was used to demonstrate that part of the specific binding of AtRALF1 to intact seedlings and to a microsomal fraction derived from the roots of Arabidopsis plants is BAK1-dependent. Moreover, AtRALF1 induces an increase in BAK1 phosphorylation, suggesting that the binding of AtRALF1 to BAK1 is functional. These findings show that BAK1 contains an additional AtRALF1 binding site, indicating that this protein may be part of a AtRALF1-containing complex as a co-receptor, and it is required for the negative regulation of cell expansion. (AU)

• Processo FAPESP: 11/17264-5 - RALF e o complexo receptor dos brassinosteróides: interação do peptídeo hormonal AtRALF1 e a proteína BAK1, uma proteína de membrana receptora quinase associada ao BRI1
• Beneficiário: Keini Dressano
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 12/13658-1 - RALF e o complexo receptor dos brassinosteróides: interação do peptídeo hormonal AtRALF1 e a proteína BAK1, uma proteína de membrana receptora quinase associada ao BRI1
• Beneficiário: Keini Dressano
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Doutorado Direto
• Processo FAPESP: 14/14487-1 - Mecanismos de percepção do peptídeo AtRALF1: seus receptores e a dissociação entre o fluxo iônico e a regulação negativa da expansão celular
• Beneficiário: Daniel Scherer de Moura
• Modalidade de apoio: Auxílio à Pesquisa - Regular