Transcriptome analysis of Chlamydomonas reinhardtii during nitrogen starvation

Nanette R. Boyle and Sabeeha S. Merchant

Chemistry and Biochemistry, UCLA, 607 Charles E. Young Dr. E, Los Angeles, CA 90034, USA

Despite widespread interest in the production of biofuels from algae, little is known about the regulatory mechanisms that induce triacylglycerol (TAG) accumulation. In C. reinhardtii, it is known that certain nutrient deprivation conditions, such as nitrogen, phosphorous and sulfur, induce TAG accumulation and we hypothesize that in response to such conditions the cells have a time-dependent response on the transcript level. Therefore, we performed time-course experiments to analyze mRNA abundance over 48 hours of nitrogen starvation using RNAseq. In our initial qPCR experiments, we have found that the three marker genes chosen (AMT1, CHL and MLDP) show three different patterns of expression. AMT1, encoding an ammonium transporter is highly expressed within 0.5 hours of N-starvation; CHL shows a peak of expression at 4 hours and MLDP peaks at 12 hours. Other genes identified by RNAseq to be significantly up/down regulated will also be presented.

e-mail address of presenting author: nboyle@chem.ucla.edu