Chlamydomonas reinhardtii cells were exposed to a sublethal concentration of thewidespread herbicide atrazine
for 3 h. Physiological cellular parameters, such as chlorophyll a fluorescence and oxidative stress monitored by
flow cytometry and pigments levels were altered in microalgal cells exposed to 0.25 μMof atrazine. Furthermore,
the effects of this herbicide on C. reinhardtii were explored using “omics” techniques. Transcriptomic analyses,
carried out by RNA-Seq technique, displayed 9 differentially expressed genes, related to photosynthesis, between
control cultures and atrazine exposed cultures. Proteomic profiles were obtained using iTRAQ tags and
MALDI-MS/MS analysis, identifying important changes in the proteome during atrazine stress; 5 proteins related
to photosynthesis were downexpressed. The results of these experiments advance the understanding of
photosynthetic adjustments that occur during an early herbicide exposure. Inhibition of photosynthesis induced
by atrazine toxicity will affect the entire physiological and biochemical states of microalgal cells.Ministerio de Economía y Competitividad; CGL2010-15993/BO
