Increasing Oil Bodies in Physcomitrella patens by Overexpressing Oil Body- Associated Proteins

In bryophytes, reproductive organs contain large amount of oil bodies (OBs), the well-known lipidcontaining structures. OBs in spores are the most prominent and have been extensively studied. They are thought to be formed by budding off the outer layer of the endoplasmic reticulum membrane (ER) due to accumulation of neutral lipids between the leaflets of the phospholipid bilayer.

In P. patens, the OBs are abundant in the mature sporophytes or during starvation, but are hardly observed in the vegetative stage. We overexpressed OB associated proteins such as oleosin, seipin, and fibrillin to increase the OB formation in P. patens vegetative tissue. As a result, we confirmed that the number of OBs were significantly increased in the protonemal cells compared to the wild type.

These structures could be used to compartmentalize, synthetically made high-value compounds in green cells.