Section: New Results

Characterizing cell membrane properties

Participants : Sylvain Prigent, Xavier Descombes, Grégoire Malandain, Hélène Barelli [IPMC] .

Some mammalian cells show striking differences in the acyl chain composition of their membrane phospholipids. In most cases, the majority of phospholipids bear one saturated and one monounsaturated acyl chains at positions 1 and 2 or the glycerol, respectively. However, some cells and notably neurons contain large amounts of phospholipids with a polyunsaturated fatty acyl chain, generally at position 2. The aim of this work is to compare the impact of the phospholipid polyunsaturation vs monounsaturation on the mechanical and functional properties of the plasma membrane.

For this task, we currently investigate how phospholipid insaturation affects the ability of specialized protein machineries involved in transport vesicle formation, by first detecting vesicles in 2D+t sequences of microscopic images of individual cells, and then tracking detected vesicles through the temporal sequences (see figure8 ) [23] .

Figure 8. Left: detection of individual vesicles in one image of the sequence. Right: resulting paths of tracked vesicles through the 2D+t sequence.