One of the most amazing stories I heard when I studied biology was about the way the cell distributes material within itself. The same net of microtubules that sustains the structure ofthe animal cell serves as a railroad to transport food and building materials. But the best is yet to come.
The ones responsible for this transport are a family of small, two legged, funny proteins called Kinesins
. Recent studies show that they actually walque along the microtubules while carrying the materials inside big vesicles located near the top of the kinesin molecule.
The goal was to fake a video in
which a kinesin could be seen carrying a huge vesicle . In principle I was concerned about the taste of the final images and not about be-ing precise in a biological sense (shame on me!). It is possible to model the kinesin using the data from the PDB (Protein Databank)
 using a script by Michael Gan-tenbrinker . Instead, I decided to make a roughly similar model with a simple armature. The movements of the kinesin were made slow to simulate both the absence of gravity and the erratic flows of fluids within the cell.
The microtubule was modelled to be a kind of organic pipe and is not realistic either. The space was filled with a bunch of moving bub-bles to simulate the cell environment which in reality happens to be much denser. These bubbles were animated using Blender physics. Finally, the camera was animated using a shaky effect .
The light is made of two sun lights with no shadows. It is important to realize that in micrographs, darker areas can be mistaken for shadows. Depending on the tech-nique, darkness depends on the density of materials, or on the angle the faces of the objects are pointing.
There are mainly two kinds of textures in this project. The ones for the kinesin and microtubules are simple materials with no specular or mirror properties. Remember that at this scale, mirroring or specularity makes no sense. Their textures are cloudy textures with slight normals. The bubbles that simulate the environment have a transparent texture with a high IOR.
Once the kinesin was animated, it was time to start working with the node editor. First of all I set a strong defocus filter with a variable depth of field. Then I added a noise layer which was blurred with a blur filter. To finish, something that in
principle is not a typical micrograph artifact but which works very well in the final scene: a lens distortion filter with variable dispersion.
And that’s all. Although, as I have said, many elements in this construction are not realistic, the final results gives a nice feeling of a living micrograph .