Manipulation of senescence and chlorophyll catabolism for yield and nutritional quality improvement

• Grant number: 14/10651-1
• Support Opportunities: Regular Research Grants
• Start date: February 01, 2015
• End date: January 31, 2017
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: Maria Magdalena Rossi
• Grantee: Maria Magdalena Rossi
• Host Institution: Instituto de Biociências (IB). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Leaf senescence initiates when photosynthetic potential riches the maximum capacity and during its progression photochemical activity decreases due to the degradation of the photosynthetic machinery and nutrients are translocated to non-senescent plant organs. Several evidences indicate that the delay of senescence maintaining the production of photosynthates for longer periods results in yield increment becoming an important agronomical trait. Chlorophyll degradation is also an interesting process for metabolic engineering aiming nutritional quality improvement. Chlorophyll dephytylation produces phytol, which is a precursor of tocopherols, compounds with vitamin E activity. These potent antioxidants have shown to protect pigments, proteins and fatty acids involved in the photosynthetic apparatus from the reactive oxygen species (ROS) produced during photosynthesis. Regarding human health, the vitamin E prevents cardiovascular diseases, cancer of mammary glands and oxidative stress caused by nicotine. Most of the studies approaching senescence and chlorophyll degradation use the model species Arabidopsis thaliana or grasses; however few reports describe these processes in freshly fruit producing plants. In this sense, Solanum lycopersicum is an excellent model not only because abundant genetic and genomic resources are available but due to the nutritional and economic importance of this species. Thus, this project proposes the study of these both processes evaluating the physiological impact of leaf senescence delay and performing a functional characterization of the dephytylating enzymes and phytol kinases (involved in phytol recycling). The results will contribute to improve our understanding about the genetic basis of agronomical important traits allowing the development of new strategies for crop breeding. (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)

ROSSI, MAGDALENA; BERMUDEZ, LUISA; CARRARI, FERNANDO. Crop yield: challenges from a metabolic perspective. Current Opinion in Plant Biology, v. 25, p. 79-89, JUN 2015. (13/50481-5, 14/10651-1)

DUARTE LUPI, ALESSANDRA CAVALCANTI; LIRA, BRUNO SILVESTRE; GRAMEGNA, GIOVANNA; TRENCH, BRUNA; RODRIGUES ALVES, FREDERICO ROCHA; DEMARCO, DIEGO; PEREIRA PERES, LAZARO EUSTAQUIO; PURGATTO, EDUARDO; FRESCHI, LUCIANO; ROSSI, MAGDALENA. Solanum lycopersicum GOLDEN 2-LIKE 2 transcription factor affects fruit quality in a light- and auxin-dependent manner. PLoS One, v. 14, n. 2, FEB 12 2019. (16/01128-9, 14/10651-1)