Functional characterization of the sugarcane (Saccharum spp.) ammonium transporter AMT2;1 suggests a role in ammonium root-to-shoot translocation

Autor(es)

Koltun, Alessandra ; Maniero, Rodolfo A. A. ; Vitti, Marielle ; de Setta, Nathalia ; Giehl, Ricardo F. H. ; Lima, Joni E. E. ; Figueira, Antonio

• Tipo de documento: Artigo Científico
• Fonte: FRONTIERS IN PLANT SCIENCE; v. 13, p. 16-pg., 2022-11-18.

Resumo

AMMONIUM TRANSPORTER/METHYLAMMONIUM PERMEASE/RHESUS (AMT) family members transport ammonium across membranes in all life domains. Plant AMTs can be categorized into AMT1 and AMT2 subfamilies. Functional studies of AMTs, particularly AMT1-type, have been conducted using model plants but little is known about the function of AMTs from crops. Sugarcane (Saccharum spp.) is a major bioenergy crop that requires heavy nitrogen fertilization but depends on a low carbon-footprint for competitive sustainability. Here, we identified and functionally characterized sugarcane ScAMT2;1 by complementing ammonium uptake-defective mutants of Saccharomyces cerevisiae and Arabidopsis thaliana. Reporter gene driven by the ScAMT2;1 promoter in A. thaliana revealed preferential expression in the shoot vasculature and root endodermis/pericycle according to nitrogen availability and source. Arabidopsis quadruple mutant plants expressing ScAMT2;1 driven by the CaMV35S promoter or by a sugarcane endogenous promoter produced significantly more biomass than mutant plants when grown in NH4+ and showed more N-15-ammonium uptake by roots and nitrogen translocation to shoots. In A. thaliana, ScAMT2;1 displayed a K-m of 90.17 mu M and V-max of 338.99 mu moles h(-1) g(-1) root DW. Altogether, our results suggest that ScAMT2;1 is a functional high-affinity ammonium transporter that might contribute to ammonium uptake and presumably to root-to-shoot translocation under high NH4+ conditions. (AU)

• Processo FAPESP: 10/11313-1 - Identificação e caracterização fisiologica e do perfil de expressão gênica de cultivares de cana-de-açúcar (saccharum spp) contrastantes para o uso eficiente de nitrogenio
• Beneficiário: Joni Esrom Lima
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 13/15989-8 - Caracterização fisiológica, bioquímica e molecular do transporte de nitrato durante a aquisição e remobilização nitrogênio em cana-de-açúcar (Saccharum spp.)
• Beneficiário: Antonio Vargas de Oliveira Figueira
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 17/00460-2 - Caracterização funcional do gene decodificador para transportador de amônio ScAMT3.3 em cana-de-açúcar (Saccharum spp.)
• Beneficiário: Rodolfo Augusto Maniero
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 16/14669-8 - Caracterização funcional de genes codificadores para transportadores de amônio em cana-de-açúcar (Saccharum spp.)
• Beneficiário: Antonio Vargas de Oliveira Figueira
• Modalidade de apoio: Auxílio à Pesquisa - Regular