SucEST - data mining

• Grant number: 99/02840-7
• Support Opportunities: Genome Research Grants
• Start date: June 01, 1999
• End date: May 31, 2002
• Field of knowledge: Biological Sciences - Biochemistry - Molecular Biology
• Principal Investigator: Antonio Vargas de Oliveira Figueira
• Grantee: Antonio Vargas de Oliveira Figueira
• Host Institution: Centro de Energia Nuclear na Agricultura (CENA). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

Identifying and understanding expression of genes responsible or associated with nutrient uptake and movement could lead to the development of more nutrient-efficient sugarcane cultivars, allowing both the reduction of fertilizer levels applied, reducing environmental impacts by fertilizer production and/or application, and the incorporation of marginal soils with low levels of fertility and/or presence of toxic levels of elements or pH. Various sequences of metal transporters have been cloned and/or characterized in plants and other systems, such as: plant phosphate transporters by Muchhal et al. 1996. PNAS 93:10519, reviewed by Raghotama, 1999, Ann. Rev Plant Phys. 50:665; a putative Ca transporter by Clemens et al. 1998 PNAS 95:12043; putative Zn transporters by Grotz et al., 1998, PNAS 95:7220; ferric-chelate reductase for iron uptake by Robinson et al., 1999, Nature 397:694; putative Copper transporter by Kaempfenkel et al., 1995, lBC 270:28479). These sequences will be used to start identification of sugarcane homologues. Another interest is the study of metal-toxicity resistance associated peptides, such as glutathione, metallothioneins and phytochelatins. Genes coding for these peptides have been identified in other plants and systems (including mammals), such as the one coding for phytochelatin synthase, and for other metal-chelating peptides, such as metallothioneins, and γ-Glu-Cys-synthetase, glutathione synthetase, and gluthatione S-transferase. Glutathione is associated with various detoxification pathways, and is a precursor of phytochelatin synthesis. Additionally, glutathione S-transferase have also been associated with herbicide resistance, and the role of the various forms of glutathione S-transferase in cellular detoxification will be investigated. Complexes of metal-phytochelatin and glutathione S-conjugates are sequestered into vacuoles by ATP binding cassette transporters that have already been cloned in Arabidopsis. All these proteins/enzymes are associated with metal resistance and/or detoxification pathways, and are pre-requisites of metal hyperaccumulation in plants. (AU)