Our new toolbox of plant membrane imaging probes: LipoTag. After CarboTag (cell wall probes), we have now developed a modular strategy to create non toxic, easy-to-use, and flexible probes for hassle-free live-cell imaging of plant membranes, and their tension, lipid order and oxidation. 🍀🔬

Previously the Type II actins were described to be angiosperm specific, but we now also identified those in the seedplants. and there is much more in the manuscript :)

I forgot to mention that seed plants have two actin types (renamed I and II), which are not interchangeable. Hence, we studied these differences in more detail and formed the hypothesis that the hydrogenbond conformations are the main determinant for the actin specialisation.

Next we were interested in the function diversification of these actin isoforms. Initially, we had high hopes for finding variable regions and found this variable patch. The AAs are not even close to each other in the sequence (eg 190&268). However, we could not find known interactors in this region

and because actin is highly conserved, we could even pinpoint specific substitutions per plant lineage that were conserved in evolution.

This indicates that the ancestral organism for each lineage only had a single actin that has been conserved in evolution. (Either there was only one, or the others were lost). Such events are marked with the orange dots in this summary tree.

We revisited the evolution of plant actins (last paper was in 1999), with the aim to understand why plants have many actin isoforms and how these isoforms can be functionally different. Strikingly, unlike e.g. the auxin response factors, actins are completely segregated per taxonomic lineage. (1/n)

Our first dive into protein evolution; revisiting the diversification of plant isoactins. Why do plants maintain so many isoactins that differ so little at a sequence level?