CSouza

Current Research

Plants are sessile organisms that must conform to the surrounding environment. Consequently, plants have developed several strategies to cope with environmental challenges, including exposure to pathogens. The field of plant-pathogen interactions is evolving rapidly, revealing an intricate signaling network that governs successful versus unsuccessful pathogen attacks.  I am interested in the role of the plant cell wall in plant defense. Plants can perceive products of cell wall degradation and initiate defense responses similar to those generated after recognition of microbial-derived molecules. I am working to identify and characterize signaling components necessary for recognition of cell wall damage, and how plants can integrate multiple “danger” signals during cell invasion to modulate the amplitude of defense responses. In addition, I am interested in understanding the downstream network of transcription factors and their role in specifying gene expression associated with plant immunity.

Previous Research

I obtained my PhD from the University of British Columbia, in beautiful Vancouver, Canada. There, I worked in the lab of Prof. Carl Douglas to characterize genes of unknown function that were potentially involved in the phenylpropanoid pathway that leads to wood formation and synthesis of plant pigments. We were particularly interested in those genes with sequence similarity to 4-coumarate:CoA ligase (4CL), a key enzyme in this pathway. While studying these unknown genes in the model plant species Arabidopsis thaliana, my research led to the identification and characterization of a gene important for pollen integrity and plant fertility. Co-expression analysis revealed a previously uncharacterized biochemical pathway conserved in plants, which helped elucidate the biochemistry and cell biology underlying sporopollenin biosynthesis, a poorly understood polymer that is required for pollen wall integrity.

After graduating I switched gears and moved to Miami, Florida to join the lab of Prof. Greg Plano at the University of Miami Miller School of Medicine, where I studied the assembly and function of the Type III secretion system (T3SS) apparatus in the bacterial pathogen Yersinia pestis, the causative agent of the bubonic plague in humans.  The Plano Lab introduced me to the exciting field of host-pathogen interactions, which is the focus of my work in Shauna Somerville's Lab here at Berkeley, now back in the plant world.

Chaudhury S, de Azevedo Souza C, Plano GV, De Guzman RN. (2015). The LcrG Tip Chaperone Protein of the Yersinia pestis Type III Secretion System Is Partially Folded. J Mol Biol. 427(19):3096-109

Kim SS, Grienenberger E, Lallemand B, Colpitts CC, Kim SY, de Azevedo Souza, C, Geoffroy P, Heintz D, Krahn D, Kaiser M, Kombrink E, Heitz T, Suh DY, Legrand M, Douglas CJ. (2010). LAP6/POLYKETIDE SYNTHASE A and LAP5/POLYKETIDE SYNTHASE B encode hydroxyalkyl α-pyrone synthases required for pollen development and sporopollenin biosynthesis in Arabidopsis thaliana. Plant Cell 12: 4045-4066

Grienenberger E, Kim S.S., Lallemand B., Geoffroy P., Heintz D., de Azevedo Souza, C., Heitz T., Douglas, C.J. and Legrand M. (2010) Analysis of TETRAKETIDE α-PYRONE REDUCTASE function in Arabidopsis thaliana reveals a previously unknown, but conserved, biochemical pathway in sporopollenin monomer biosynthesis. Plant Cell 12: 4067-4083

de Azevedo Souza, C., Kim, S.S., Koch, S., Kienow, L., Schneider, K., McKim, S.M., Haughn, G.W., Kombrink, E. and Douglas, C. (2009) A novel fatty acyl-CoA synthetase is required for pollen development and sporopollenin biosynthesis in Arabidopsis. Plant Cell 21: 507-525

de Azevedo Souza, C., Barbazuk, B., Ralph, S., Bohlmann, J., Hamberger, B., and Douglas, C. (2008). Genome-wide analysis of a land plant-specific Acyl:coenzymeA synthetase (ACS) gene family in Arabidopsis, poplar, rice, and Physcomitrella. New Phytol. 179: 987– 1003.

Hamberger, B., Ellis, M., Friedmann, M., de Azevedo Souza, C., Barbazuk, B., and Douglas, C. (2007). Genome-wide analyses of phenylpropanoid-related genes in Populus trichocarpa, Arabidopsis thaliana, and Oryza sativa: The Populus lignin toolbox and conservation and diversification of angiosperm gene families. Can. J. Bot. 85: 1182–1201.

When I was accepted to the Biology Program at the University of Sao Paulo, Brazil, I was on my way to becoming a scientist! I never thought I would be interested in teaching until my first class in college. It blew my mind on how a well-structured course, taught by enthusiastic professors, could be so inspiring. I loved it so much that in my second year of undergraduate studies I signed up to be a teaching assistant and tour the newly arrived students around our demonstration gardens, help direct labs and guide field trips. That first teaching experience really opened my eyes to the importance of effective communication and how enthusiasm can be contagious. Since then, I haven’t stop being involved with teaching. In addition to training several undergraduates and junior grad students in the lab throughout the years, I taught Plant Physiology for 5 years at UBC, and now am involved in teaching Plant-Microbe Interactions course here at Berkeley. I love to interact with students. You really know your stuff when you can teach it to someone!