Study of carotenoid metabolism and regulation in plant models

Host: Professor Salim Al-Babili

Abstract:
Carotenoids are isoprenoid compounds with essential functions in photosynthetic organisms. In plants, carotenoids are synthesized in the plastids and play key roles in primary metabolism, regulation of plant growth, biotic and abiotic stresses responses and signaling. In my current research, I use genetic engineering approaches to manipulate gene expression of LCYB gene to modify carotenoid/isoprenoid fluxes and study its impact on plant biomass and photosynthetic efficiency. Stable manipulation of tobacco nuclear DNA (carrot LCYB1 nuclear gene transformation) showed that an increase in gene expression and metabolites of important plastidial pathways (carotenoid, chlorophylls, and abscisic acid:ABA/gibberellins:GAs) allow changes in plant architecture and increases in photosynthetic efficiency in tobacco. In addition, I used plastid DNA transformation to achieve higher expression levels of the DcLCYB1 gene in tobacco in an attempt to boost further plant yield. DcLCYB1 transplastomic lines showed increased carotenoid content and LCYB activity, but not in chlorophylls, ABA or GAs, and therefore plant yield remain unaltered in these lines. In contrast, plants with reduced LCYB expression levels showed the opposite behavior resulting in delayed development and decreased photosynthetic efficiency. Results found here indicate that proper expression of LCYB gene could influence positively/negatively plant yield as consequence of multifactorial molecular events (e.g. increased pigment content, gene expression of carotenoid and carotenoid-related pathways, photosynthetic efficiency, and hormone levels). This bioengineering approach suggests LCYB as a target gene to modify not only the nutritional content of a desire crop but also to increase plant yield, photosynthetic efficiency and stress tolerance.
 
Biography:
EDUCATION:
2004-2010. Molecular Biotechnology Engineering “Maximum distinction”. “Evaluation of the Functionality of Carrot Lycopene β-cyclase Genes by Means of Heterologous Complementation”. Facultad de Ciencias, Universidad de Chile, Santiago, Chile. Supervisor: Dr. Claudia Stange.
2010-2012. Mcs. in Biological Sciences with mention in Molecular Biology, Cellular Biology and Neurosciences “Maximum distinction”. CONICYT scholarship. “Characterization of Daucus carota lycopene β-cyclase gene (DcLCYB1) by over-expression in plant models: Nicotiana tabacum and D. carota”. Facultad de Ciencias, Universidad de Chile, Santiago, Chile. Supervisor: Dr. Claudia Stange.
2012-2016. PhD in Molecular Plant Physiology “Magna Cum Laude”. Deutscher Akademischer AustauschDienst (DAAD) scholarship. “Characterization of the Clp protease complex and identification of putative substrates in N. tabacum”. Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany. Supervisor: Ralph Bock.
 
WORK AND RESEARCH EXPERIENCE:
2016-present. Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany. Postdoctoral fellow; Advisor: Lothar Willmitzer/Aleksandra Skirycz. Topics: “Unraveling the function of dipeptides in plants”/ “Increased β-carotene levels allows bigger plant productivity by redesigning plant architecture and improvement of photosynthetic efficiency”/”Finding the receptors of the signaling molecules β-cc and dhA in Tobacco and Arabidopsis”.
2012-2016. PhD thesis at Max Planck Institute. Topic: “Plastid proteolysis and identification of Clp substrates in N. tabacum”.
2010-2012. Master thesis. Topic: “Manipulation of carotenoid metabolism in plant models: Nicotiana tabacum and D. carota”.
2009-2010. Undergraduate thesis. Topic: “Assesing the Functionality of Carrot Lycopene β-cyclase Genes by Means of Heterologous Complementation in E. coli”.
 

Speakers

Juan Beltran
Bldg3

Event Quick Information

Date
01 Mar, 2020
Time
02:00 PM - 03:00 PM
Venue
Building 3 - Level 5 - Room 5209