title: Malate-dependent Fe accumulation is a critical checkpoint in the root developmental response to low phosphate.
abstract: Low phosphate (Pi) availability constrains plant development and seed production in both natural and agricultural ecosystems. When Pi is scarce, modifications of root system architecture (RSA) enhance the soil exploration ability of the plant and lead to an increase in Pi uptake. InArabidopsis, an iron-dependent mechanism reprograms primary root growth in response to low Pi availability. This program is activated upon contact of the root tip with low-Pi media and induces premature cell differentiation and the arrest of mitotic activity in the root apical meristem, resulting in a short-root phenotype. However, the mechanisms that regulate the primary root response to Pi-limiting conditions remain largely unknown. Here we report on the isolation and characterization of two low-Pi insensitive mutants (lpi5andlpi6), which have a long-root phenotype when grown in low-Pi media. Cellular, genomic, and transcriptomic analysis of low-Pi insensitive mutants revealed that the genes previously shown to underlieArabidopsisAl tolerance via root malate exudation, known as SENSITIVE TO PROTON RHIZOTOXICITY (STOP1) and ALUMINUM ACTIVATED MALATE TRANSPORTER 1 (ALMT1), represent a critical checkpoint in the root developmental response to Pi starvation inArabidopsis thalianaOur results also show that exogenous malate can rescue the long-root phenotype oflpi5andlpi6Malate exudation is required for the accumulation of Fe in the apoplast of meristematic cells, triggering the differentiation of meristematic cells in response to Pi deprivation.
authors.affiliation: Laboratorio Nacional de Genómica para la Biodiversidad/Unidad de Genómica Avanzada, Centro de Investigación y Estudios Avanzados, Instituto Politécnico Nacional, 36821 Irapuato, Guanajuato, México.
authors.forename: Javier
authors.initials: J
authors.lastname: Mora-Macías
authors.affiliation: Laboratorio Nacional de Genómica para la Biodiversidad/Unidad de Genómica Avanzada, Centro de Investigación y Estudios Avanzados, Instituto Politécnico Nacional, 36821 Irapuato, Guanajuato, México.
authors.forename: Jonathan Odilón
authors.initials: JO
authors.lastname: Ojeda-Rivera
authors.affiliation: Laboratorio Nacional de Genómica para la Biodiversidad/Unidad de Genómica Avanzada, Centro de Investigación y Estudios Avanzados, Instituto Politécnico Nacional, 36821 Irapuato, Guanajuato, México.
authors.forename: Dolores
authors.initials: D
authors.lastname: Gutiérrez-Alanís
authors.affiliation: Laboratorio Nacional de Genómica para la Biodiversidad/Unidad de Genómica Avanzada, Centro de Investigación y Estudios Avanzados, Instituto Politécnico Nacional, 36821 Irapuato, Guanajuato, México.
authors.forename: Lenin
authors.initials: L
authors.lastname: Yong-Villalobos
authors.affiliation: Laboratorio Nacional de Genómica para la Biodiversidad/Unidad de Genómica Avanzada, Centro de Investigación y Estudios Avanzados, Instituto Politécnico Nacional, 36821 Irapuato, Guanajuato, México.
authors.forename: Araceli
authors.initials: A
authors.lastname: Oropeza-Aburto
authors.affiliation: Laboratorio Nacional de Genómica para la Biodiversidad/Unidad de Genómica Avanzada, Centro de Investigación y Estudios Avanzados, Instituto Politécnico Nacional, 36821 Irapuato, Guanajuato, México.
authors.forename: Javier
authors.initials: J
authors.lastname: Raya-González
authors.affiliation: Laboratorio Nacional de Genómica para la Biodiversidad/Unidad de Genómica Avanzada, Centro de Investigación y Estudios Avanzados, Instituto Politécnico Nacional, 36821 Irapuato, Guanajuato, México.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Jiménez-Domínguez
authors.affiliation: Laboratorio Nacional de Genómica para la Biodiversidad/Unidad de Genómica Avanzada, Centro de Investigación y Estudios Avanzados, Instituto Politécnico Nacional, 36821 Irapuato, Guanajuato, México.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Chávez-Calvillo
authors.affiliation: Laboratorio Nacional de Genómica para la Biodiversidad/Unidad de Genómica Avanzada, Centro de Investigación y Estudios Avanzados, Instituto Politécnico Nacional, 36821 Irapuato, Guanajuato, México.
authors.forename: Rubén
authors.initials: R
authors.lastname: Rellán-Álvarez
authors.affiliation: Laboratorio Nacional de Genómica para la Biodiversidad/Unidad de Genómica Avanzada, Centro de Investigación y Estudios Avanzados, Instituto Politécnico Nacional, 36821 Irapuato, Guanajuato, México lherreae@cinvestav.mx.
authors.forename: Luis
authors.initials: L
authors.lastname: Herrera-Estrella
mesh_terms: D017360:Arabidopsis / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000378:metabolism; D007501:Iron / Q000378:metabolism*; D008293:Malates / Q000378:metabolism*; D018519:Meristem / Q000254:growth & development*; D027361:Organic Anion Transporters / Q000378:metabolism; D010710:Phosphates / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism
chemical_list: C512361:ALMT1 protein, Arabidopsis; D029681:Arabidopsis Proteins; D008293:Malates; D027361:Organic Anion Transporters; D010710:Phosphates; C525886:STOP1 protein, Arabidopsis; D014157:Transcription Factors; C030298:malic acid; D007501:Iron
keywords: cell differentiation; gene regulation; iron; phosphate; root response