Genetic chloroplast transformation with rbcL mutant gene for photorrespiration studies in tabacco

• Grant number: 13/03793-1
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: July 01, 2013
• End date: June 30, 2014
• Field of knowledge: Biological Sciences - Biochemistry - Molecular Biology
• Principal Investigator: Helaine Carrer
• Grantee: Fernanda Smaniotto Campion
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

Rubisco is the key enzyme for carbon fixation in photosynthesis. However, besides carbon fixation, this enzyme is also capable of catalyzing oxidation reactions by a process called photorespiration, which leads to fixed carbon loss and the consumption of ATP and NADPH. For its great importance in both processes cited, RUBISCO has been the target of several studies. This enzyme is a complex protein composed of 16 subunits, in which 8 small subunits are codified by the rbcS gene and 8 large subunits are codified by the rbcL gene located in the nucleus and chloroplast genome, respectively. This research has as objective to substitute the rbcL gene in tobacco chloroplasts with a mutant gene in which the alanine 375 is replaced by a valine aiming the decrease oxygenation by RUBISCO, which can lead to lower rates of photorespiration and then, increase the efficiency of photosynthesis in plants. (AU)