title: APSR1, a novel gene required for meristem maintenance, is negatively regulated by low phosphate availability.
abstract: Proper root growth is crucial for anchorage, exploration, and exploitation of the soil substrate. Root growth is highly sensitive to a variety of environmental cues, among them water and nutrient availability have a great impact on root development. Phosphorus (P) availability is one of the most limiting nutrients that affect plant growth and development under natural and agricultural environments. Root growth in the direction of the long axis proceeds from the root tip and requires the coordinated activities of cell proliferation, cell elongation and cell differentiation. Here we report a novel gene, APSR1 (Altered Phosphate Starvation Response1), involved in root meristem maintenance. The loss of function mutant apsr1-1 showed a reduction in primary root length and root apical meristem size, short differentiated epidermal cells and long root hairs. Expression of APSR1 gene decreases in response to phosphate starvation and apsr1-1 did not show the typical progressive decrease of undifferentiated cells at root tip when grown under P limiting conditions. Interestingly, APSR1 expression pattern overlaps with root zones of auxin accumulation. Furthermore, apsr1-1 showed a clear decrease in the level of the auxin transporter PIN7. These data suggest that APSR1 is required for the coordination of cell processes necessary for correct root growth in response to phosphate starvation conceivably by direct or indirect modulation of PIN7. We also propose, based on its nuclear localization and structure, that APSR1 may potentially be a member of a novel group of transcription factors.
authors.affiliation: Laboratorio Nacional de Genómica para la Biodiversidad, Centro de Investigación y Estudios Avanzados, Campus Guanajuato, Km. 9.6 Libramiento Norte Carr. Irapuato-León, Irapuato, Guanajuato, Mexico.
authors.forename: Víctor
authors.initials: V
authors.lastname: González-Mendoza
authors.forename: Andrés
authors.initials: A
authors.lastname: Zurita-Silva
authors.forename: Lenin
authors.initials: L
authors.lastname: Sánchez-Calderón
authors.forename: María Eugenia
authors.initials: ME
authors.lastname: Sánchez-Sandoval
authors.forename: Araceli
authors.initials: A
authors.lastname: Oropeza-Aburto
authors.forename: Dolores
authors.initials: D
authors.lastname: Gutiérrez-Alanís
authors.forename: Fulgencio
authors.initials: F
authors.lastname: Alatorre-Cobos
authors.forename: Luis
authors.initials: L
authors.lastname: Herrera-Estrella
mesh_terms: D017360:Arabidopsis / Q000166:cytology / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D001692:Biological Transport; D002454:Cell Differentiation; D018506:Gene Expression Regulation, Plant; D007210:Indoleacetic Acids / Q000378:metabolism; D018519:Meristem / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D008958:Models, Molecular; D009154:Mutation; D009928:Organ Specificity; D010641:Phenotype; D010710:Phosphates / Q000172:deficiency*; D010802:Phylogeny; D019441:Plant Epidermis / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D010937:Plant Growth Regulators / Q000378:metabolism; D018517:Plant Roots / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D018520:Plant Shoots / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D011993:Recombinant Fusion Proteins; D036226:Seedlings / Q000166:cytology / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D017422:Sequence Analysis, DNA; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D007210:Indoleacetic Acids; D010710:Phosphates; D010937:Plant Growth Regulators; D011993:Recombinant Fusion Proteins; D014157:Transcription Factors; C583308:APSR1 protein, Arabidopsis; C117013:AT5G57090 protein, Arabidopsis; C479554:PIN7 protein, Arabidopsis