Animation case study

Three short stories about transport through the nuclear pore

I create didactic animations for the Hoelz Lab at CalTech on a contract basis. These animations were born from a simple 2D schematic I created for their “Figure 1” summary image of the NPC. The videos are submitted as supplemental material and shown in talks alongside the 2D schematic and other figures. This group is very consistent with the color and shape of nucleoporins across all of their work, so what I create needs to be consistent with the already established language. The style needs to not deviate far from the look of their figures as they would usually be viewed together, with a key. The audience in this case is fellow scientists with an interest in the nuclear pore, in particular how it operates during macromolecular transport.

Above is the original 2D “figure 1” schematic followed by several reference images and examples of author-created figures. My research consisted of understanding figures such as these, reading manuscripts, studying Chimera sessions and molecular simulations, and regular discussions with the client.

Animations and storyboards for the three animations follow:

Import and export

Simplifying protein shapes based on their function and conformational changes, this animation shows an example of how cargo may travel in and out of the NPC. The proteins are given some pep in their movements to exaggerate the action and give them subtle personality.

Transmembrane transport

This animation focuses on cargo transport into the nucleus via a transmembrane protein. This is an introduction to the concept that the pore must somehow be able to dilate in order for proteins to travel along the membrane and squeeze themselves through any two spokes.

Understanding dilation

This animation is currently in production; what you see here is a near-final draft from which I will get client feedback and make lighting and timing improvements.

Very recently there has been a flurry of work released that describes the dilation and contraction of the pore. The Hoelz lab discovered dainty, disordered, flexible linkers that connect the inner ring nucleoporins, acting like elastic bands between the layers and between adjacent spokes. They also wanted to show the newly elucidated lumenal ring.

These linkers have never been visualized before- this was a great opportunity to be the first to interpret this didactically.

Dr. Hoelz wanted viewers to walk away with a more three-dimensional understanding of the locations, function, and elastic motion of the linkers that could not be communicated in static images.

To achieve this, I begin at a whole-pore level then drill down into a more detailed view of just the inner ring in order to best observe these elusive linkers. This focused view transitions the proteins from the very generalized arcs to slightly more descriptive shapes that following the scheme set by their paper figures. We intentionally did not want to use the real protein structures here for the sake of clarity. I created the network of proteins and linkers with an xpresso node to allow me to make edits more easily down the line.