Diet quality determines lipase gene expression and lipase/esterase activity in .

We studied the short- (12 h) and long-term (144 h) response of lipases to quality shifts in diets consisting of different mixtures of the green alga with the cyanobacterium , two species with contrasting lipid compositions. The lipase/esterase activity in both the gut and the body tissues had fast responses to the diet shift and increased with higher dietary contributions of When screening the genome for TAG lipases, we discovered a large gene-family expansion of these enzymes. We used a subset of eight genes for mRNA expression analyses and distinguished between influences of time and diet on the observed gene expression patterns. We identified five diet-responsive lipases of which three showed a sophisticated short- and long-term pattern of expression in response to small changes in food-quality. Furthermore, the gene expression of one of the lipases was strongly correlated to lipase/esterase activity in the gut suggesting its potentially major role in digestion. These findings demonstrate that the lipid-related enzymatic machinery of is finely tuned to diet and might constitute an important mechanism of physiological adaptation in nutritionally complex environments.