Generation of Chlamydomonas strains that efficiently express transgenes

Juliane Neupert, Daniel Karcher and Ralph Bock

Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany

One of the major limitations in Chlamydomonas reinhardtii research is the disappointingly poor expression of nuclear transgenes. For example, in contrast to higher plants, the limited transgene expression capacity in Chlamydomonas usually does not permit subcellular localization studies with GFP or YFP fusion proteins. Likewise, as high expression levels of recombinant protein are key to the low-cost production of pharmaceutical proteins like vaccines and antibodies, the low transgene expression levels in Chlamydomonas severely hamper the use of the alga in plant biotechnology. The reasons for the poor expression of transgenes in Chlamydomonas reinhardtii are not understood, but it is generally assumed that epigenetic gene silencing, low transcription rates and/or unusual codon usage could be involved. To overcome this limitation, we have developed Chlamydomonas strains that express introduced transgenes to high levels. The strategy for creating these strains and selected applications will be discussed.

e-mail address of presenting author: RBock@mpimp-golm.mpg.de