Carbon metabolism, kinases, and low temperature responses in eucalyptus: looking for metabolic connections

• Grant number: 14/01200-6
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• Effective date (Start): March 01, 2014
• Effective date (End): December 31, 2014
• Field of knowledge: Agronomical Sciences - Agronomy - Crop Science
• Principal Investigator: Paulo Mazzafera
• Grantee: Adilson Pereira Domingues Júnior
• Supervisor: Lothar Willmitzer
• Host Institution: Instituto de Biologia (IB). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Research place: Max Planck Society, Potsdam, Germany
• Associated to the scholarship: 11/02575-5 - Physiological and molecular responsesof Eucalyptus globulus and E. grandis to cold stress, BP.DR

Abstract

Due the sessile nature of the plants, they have to be capable to cope with different stresses, such as water restriction, extreme temperature variation, soil salinity and fertility, etc. Stresses decrease the growth as plants change their metabolism to achieve a new homeostasis. Responses to cold are related to changes in carbon metabolism associated to CBF (C-repeat binding factor) network activation. As other stresses, the changes in sugar biosynthesis observed during low temperatures can activate the SnRK1 system, a kinase network responsible to perceive and control the balance between plant energetic status and its growth rate. Important anabolic events are repressed when SnRK1 system is activated including the plant cell wall biosynthesis. Cellulose and lignin are the principal compounds of the cell wall and compete with other sinks by sugar substrates. Moreover, both polymers are the main constituent of wood, which is destined to pulp and cellulose industries. Eucalyptus species are the most common source to these industries. In Brazil, E. grandis is well acclimated to local environmental conditions, but removal of lignin during the cellulose extraction is costly. Because a different lignin composition, the pulping process is less expensive in E. globulus, a specie that grows better in cold environments. Our previous analyses have shown a differential CBF network activation and carbon metabolism control of E. grandis and E. globulus under 8ºC and 25ºC. The aim of this work is to investigate how CBF network affects the SnRK1 system using the plant model Arabidopsis thaliana and eucalyptus species. Combining these data with the systems biology theory, we expect to develop new approaches to improve the cellulose production and/or reduce the costs of lignin removal by chemical industries. (AU)