Characterization of the absorption of urea via aquaporins and its possible direct assimilation by Vriesea gigantea (Bromeliaceae)

• Grant number: 13/09097-7
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: August 01, 2013
• End date: June 30, 2017
• Field of knowledge: Biological Sciences - Botany - Pant Physiology
• Principal Investigator: Helenice Mercier
• Grantee: Alejandra Matiz Lopez
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated scholarship(s): 15/23210-6 - Analysis of urea assimilation in Vriesea gigantea (Bromeliaceae) plants with low urease activity: is mandatory the urea hydrolysis for its assimilation?, BE.EP.DR 14/26415-5 - Analysis of urea transport through aquaporins of Vriesea gigantea (Bromeliaceae) by heterologous expression in Xenopus laevis oocytes, BE.EP.DR

Abstract

Urea has been characterized as an important organic nitrogen and carbon source for bromeliads. Previous studies performed in the Plant Development Physiology Laboratory showed a high preference for urea by the tank-bromeliad Vriesea gigantea and its possible transport via aquaporins. Recent surveys obtained in our laboratory also suggested increased expression of VgPIP1,5 and VgTIP2, two aquaporins cloned in this species when the plants were kept in urea. Processes such as absorption and assimilation of urea still are unknown. It has been suggested that urea is firstly hydrolyzed by urease enzyme and is then assimilated via GS/GOGAT. Nevertheless, it could be possible that in some cases this process could also happen through a direct via, where urea would be incorporated directly into an organic compound. Low urease activity in the leaves of young plants of Vriesea gigantea was observed so, urea assimilation in these plants could occur through a direct via. In this project, young plants of Vriesea gigantea of approximately 1,5 years old will be kept in labeled urea (C13 and N15) and an urease inhibitor. The assimilation process will be analyzed using an isotopic profile study in root and in the basal and apical portions of the leaves. Additionally, the urea absorption process will be analyzed through the expression profile of aquaporin genes VgPIP1,5 and VgTIP2 when the plants will be treated with urea or equivalent amounts of nitrogen in the form of ammonium. Besides that, the transport of water and urea via Vg PIP 1,5 and VgTIP2 will be functionally characterized by a radiotracer uptake study in Xenopus laevis oocytes. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

MATIZ, ALEJANDRA; CAMBUI, CAMILA AGUETONI; RICHET, NICOLAS; MIOTO, PAULO TAMASO; GOMES, FERNANDO; PIKART, FILIPE CHRISTIAN; CHAUMONT, FRANCOIS; GASPAR, MARILIA; MERCIER, HELENICE. Involvement of aquaporins on nitrogen-acquisition strategies of juvenile and adult plants of an epiphytic tank-forming bromeliad. PLANTA, v. 250, n. 1, p. 319-332, JUL 2019. (13/09097-7, 11/50637-0)

MATIZ, A.; MIOTO, P. T.; AIDAR, M. P. M.; MERCIER, H.. Utilization of urea by leaves of bromeliad Vriesea gigantea under water deficit: much more than a nitrogen source. Biologia Plantarum, v. 61, n. 4, p. 751-762, DEC 2017. (13/09097-7, 11/50637-0)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

LOPEZ, Alejandra Matiz. Characterization of assimilation and aquaporin-dependent uptake of urea in Vriesea gigantea (Bromeliaceae). 2017. Doctoral Thesis - Universidade de São Paulo (USP). Instituto de Biociências (IBIOC/SB) São Paulo.