The Relationship of Triacylglycerol and Starch Accumulation to Carbon and Energy Flows during Nutrient Deprivation in Chlamydomonas reinhardtii.

Because of the potential importance of algae for green biotechnology, considerable effort has been invested in understanding their responses to nitrogen deprivation. The most frequently invoked reasons proposed for the accumulation of high cellular levels of triacylglycerol (TAG) and starch are variants of what may be termed the "overflow hypothesis." According to this, growth inhibition results in the rate of photosynthetic energy and/or carbon input exceeding cellular needs; the excess input is directed into the accumulation of TAG and/or starch to prevent damage.

The regulation of photosynthetic structure and function during nitrogen deprivation in Chlamydomonas reinhardtii.

The accumulation of carbon storage compounds by many unicellular algae after nutrient deprivation occurs despite declines in their photosynthetic apparatus. To understand the regulation and roles of photosynthesis during this potentially bioenergetically valuable process, we analyzed photosynthetic structure and function after nitrogen deprivation in the model alga Chlamydomonas reinhardtii. Transcriptomic, proteomic, metabolite, and lipid profiling and microscopic time course data were combined with multiple measures of photosynthetic function.