|DOI / URL||link|
|Title (Primary)||Transcriptome sequencing of a keystone aquatic herbivore yields insights on the temperature-dependent metabolism of essential lipids|
|Author||Windisch, H.S.; Fink, P.;|
|POF III (all)||T32;|
Nutritional quality of phytoplankton is a major determinant of the trophic transfer efficiency at the plant-herbivore interface in freshwater food webs. In particular, the phytoplankton’s content of the essential polyunsaturated omega-3 fatty acid eicosapentaenoic acid (EPA) has been repeatedly shown to limit secondary production in the major zooplankton herbivore genus Daphnia. Despite extensive research efforts on the biological model organism Daphnia, and the availability of several Daphnia genomes, little is known regarding the molecular mechanisms underlying the limitations in Daphnia related to dietary EPA availability.
We used RNA-seq
to analyse the transcriptomic response of Daphnia magna which were fed with two
different diets — each with or without supplementation of EPA — at two
different temperature levels (15 and 20 °C). The transcripts were mapped to the
D. magna genome assembly version 2.4, containing 26,646 translations. When D.
magna fed on green alga, changing the temperature provoked a differential
expression of 2001 transcripts, and in cyanobacteria-fed daphnia, 3385
transcripts were affected. The supplementation of EPA affected 1635 (on the
green algal diet), or 175 transcripts (on the cyanobacterial diet),
respectively. Combined effects for diet and temperature were also observed (669
for the green algal and 128 transcripts for the cyanobacterial diet). Searching
for orthologous genes (COG-analysis) yielded a functional overview of the
altered transcriptomes. Cross-matched transcript sets from both feed types were
compiled to illuminate core responses to the factors temperature and
Our highly controlled eco-physiological experiments revealed an orchestrated response of genes involved in the transformation and signalling of essential fatty acids, including eicosanoid-signalling pathways with potential immune functions. We provide an overview of downstream-regulated genes, which contribute to enhance growth and reproductive output. We also identified numerous EPA-responsive candidate genes of yet unknown function, which constitute new targets for future studies on the molecular basis of EPA-dependent effects at the freshwater plant-herbivore interface.
|Persistent UFZ Identifier||https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=22462|
|Windisch, H.S., Fink, P. (2019):
Transcriptome sequencing of a keystone aquatic herbivore yields insights on the temperature-dependent metabolism of essential lipids
BMC Genomics 20 , art. 894