Sam Wilken

A fortuitous convergence of my PhD work on jamming and my postdoc research on biomolecular phase separation. Never hesitate to step into a new field—you always carry the concepts and intuition from your past with you.

Excited to see this published! We show that multiple distinct liquid phases can be engineered within a single sample—and that, when densely packed, they behave collectively as a jammed multicomponent material that undergoes a coalescence-driven unjamming phase transition.

This paper holds personal significance for me, as it was my first foray into biomolecular phase separation and DNA self-assembly. I am continuing work on reaction-condensation mechanisms in my new independent group at @unimainz.bsky.social. Stay tuned for more!

Condensation and activator/repressor control of a transcription-regulated biomolecular liquid Cells operate in part by compartmentalizing chemical reactions. For example, recent work has shown that chromatin, the material that contains the cell's genome, can auto-regulate its structure by util...

Read the full paper here: doi.org/10.1039/D5SM...
Huge thanks to @oasaleh.bsky.social, Gabi Abraham, and the Keck Foundation for their support on work that bridged into many new areas for me.

Such feedback loops could underlie how cells control condensates, or how synthetic systems might be built to compute or regulate via phase transitions.

This work shows how biochemistry (transcription) and materials (phase separation) are interconnected:
- The reaction controls the material state (condensed liquid droplets).
- The material state controls the reaction.

We then engineered negative feedback: the formation of droplets activates condensation, but the droplets repress transcription by sequestering parts of the transcription machinery (template DNA vs RNAP).

A mesoscale “activator/repressor” network.

We found that droplet formation through this transcription-driven route shows: 1) a substantial delay before droplets appear. 2) a non-linear response of droplet volume to RNA production kinetics.

We built a minimal model system: DNA nanostars (self-assembling particles) that only form droplets when a single-stranded RNA linker is present. In vitro transcription reaction (using T7 RNAP) that produces RNA linkers in situ.

It has been shown that transcribed genes participate in liquid-liquid phase separation (LLPS) and that LLPS can condense around regions of the genome, regulating transcription. We wanted to ask: What physical mechanisms are responsible for transcription-condensation coupling?

Condensation and activator/repressor control of a transcription-regulated biomolecular liquid Cells operate in part by compartmentalizing chemical reactions. For example, recent work has shown that chromatin, the material that contains the cell's genome, can auto-regulate its structure by util...

We’re excited to share our new work in Soft Matter: doi.org/10.1039/D5SM...
We demonstrate how in vitro transcription can drive biomolecular phase separation — and how that phase separation in turn regulates transcription.

Only two days left to apply for positions in my new group in Mainz! The Nature Jobs posting will close on July 11th, but you can still find application details at: sites.google.com/view/swilken/we-are-hiring

Lots to learn about DNA (and otherwise) in Mainz, looking forward to your visit!

Fully-funded Postdoc or PhD student positions - experimental DNA biomaterials/soft matter physics - Mainz, Rheinland-Pfalz (DE) job with Wilken Lab, Johannes Gutenberg University | 12840165 Two fully-funded postdoctoral or PhD student positions in experimental mesoscale bioinspired materials, DNA nanoscience, and/or soft matter physics...

Fully funded postdoc & PhD positions available in experimental DNA biomaterials & soft matter physics! @unimainz.bsky.social‬
More info & apply here (by July 11th) ⬇️
www.nature.com/naturecareers/job/12840165
#Postdoc #PhD #Biophysics #SoftMatter #Biomaterials #JobOpportunity