RESUMO
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.
Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Fosfatos/deficiência , Arabidopsis/citologia , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Transporte Biológico , Diferenciação Celular , Ácidos Indolacéticos/metabolismo , Meristema/citologia , Meristema/genética , Meristema/crescimento & desenvolvimento , Meristema/metabolismo , Modelos Moleculares , Mutação , Especificidade de Órgãos , Fenótipo , Filogenia , Epiderme Vegetal/citologia , Epiderme Vegetal/genética , Epiderme Vegetal/crescimento & desenvolvimento , Epiderme Vegetal/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/citologia , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Brotos de Planta/citologia , Brotos de Planta/genética , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Proteínas Recombinantes de Fusão , Plântula/citologia , Plântula/genética , Plântula/crescimento & desenvolvimento , Plântula/metabolismo , Análise de Sequência de DNA , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Introducción. La neumología intervencionista es un campo que se impone cada vez más en el mundo, y necesita el concurso de la anestesia. Se pretende mostrar la experiencia reunida en un centro hospitalario durante un año en el manejo anestésico de este tipo de procedimientos. Métodos. Estudio descriptivo de serie de casos. Resultados. Durante un año se llevaron a cabo 16 procedimientos en 14 pacientes, en un mismo centro. Se practicaron biopsias transbronquiales, fotocoagulación y plastias neumáticas, con inserción de stents traqueales y bronquiales. Las técnicas anestésicas fueron diversas: desde la anestesia local y la sedación superficial hasta la anestesia general, con medicamentos de uso común en nuestro medio. No se presentaron complicaciones mayores. Discusión. Se discuten las técnicas anestésicas empleadas comparándolas con las reportadas en la literatura mundial, las complicaciones y las limitaciones del estudio. Conclusiones. La anestesia para procedimientos de neumología intervencionista es variable, adaptada a las condiciones del paciente, buscando mantener la seguridad de este, y concertada con el neumólogo tratante.
Introduction. Interventional pulmonology is an increasingly popular area around the world and requires anesthesia. The objective is to share theexperience accumulated at a hospital center in one year of anesthesia management for this type of procedures.Methods. Case series study. Results. 16 procedures were performed in 14patients in one year, at the same institution. The procedures included transbronchial biopsies, photocoagulation and pneumatic-plasty with insertion of tracheal and bronchial stents. The anesthetic techniques were varied and included local anesthesia and superficial sedation as well as general anesthesia with agents commonlyused in our environment. No serious complications occurred. Discussion. The anesthesia techniques used are discussed and compared against those reported in the world literature, as well as the complications and limitations of the study.