Physics of the perfect cacio e pepe sauce https://arstechni.ca/N29zy #phaseseparation #fluiddynamics #Foodscience #rheology #Science #Physics

PRPP amidotransferase (PPAT) is rate-limiting in purine synthesis. This study shows that PPAT forms intracellular #condensates in response to high purine demand via #PhaseSeparation (driven by TORC1-mediated macromolecular crowding of cytoplasm) @PLOSBiology https://plos.io/3Yw2VVb

Cooking Perfect Cacio e Pepe

In cooking, sometimes the simplest recipes are the toughest to master. Cacio e pepe — a classic three-ingredient Italian pasta — is an excellent example. Made properly, the sauce of cheese and black pepper combines with starchy water to coat the pasta in a uniform, cheesy sauce. Or, if you’re me, you wind up with a pasta sauce flecked with stringy clumps of melted cheese. Fortunately for those of us who have yet to master this one, a new research paper has us covered with tips to make the perfect cacio e pepe.

The key to that elusive silky sauce, they found, is the starch – water – cheese combination. Your water needs just the right amount of starch — they found that between 1 – 4% starch by (cheese) mass worked. If the starch concentration is too low (which can easily happen in pasta water), you’ll get the clumpy cheese mess that so frequently happens in my kitchen. Temperature is also critical; if the water is too hot when it’s added, then it can destabilize the sauce. Check out the pre-print’s Section V for the scientific, supposedly foolproof, recipe. I know I’ll be trying it! (Image credit: O. Kadaksoo; research credit: G. Bartolucci et al. pre-print; via APS News)

#cooking #emulsion #fluidDynamics #phaseSeparation #physics #rheology #science #softMatter

Why Icy Giants Have Strange Magnetic Fields

When Voyager 2 visited Uranus and Neptune, scientists were puzzled by the icy giants’ disorderly magnetic fields. Contrary to expectations, neither planet had a well-defined north and south magnetic pole, indicating that the planets’ thick, icy interiors must not convect the way Earth’s mantle does. Years later, other researchers suggested that the icy giants’ magnetic fields could come from a single thin, convecting layer in the planet, but how that would look remained unclear. Now a scientist thinks he has an answer.

When simulating a mixture of water, methane, and ammonia under icy giant temperature and pressure conditions, he saw the chemicals split themselves into two layers — a water-hydrogen mix capable of convection and a hydrocarbon-rich, stagnant lower layer. Such phase separation, he argues, matches both the icy giants’ gravitational fields and their odd magnetic fields. To test whether the model holds up, we’ll need another spacecraft — one equipped with a Doppler imager — to visit Uranus and/or Neptune to measure the predicted layers firsthand. (Image credit: NASA; research credit: B. Militzer; via Physics World)

#convection #fluidDynamics #Neptune #numericalSimulation #phaseSeparation #physics #planetaryScience #science #Uranus

TGF-β-induced DACT1 biomolecular condensates repress Wnt signalling to promote bone metastasis
https://www.nature.com/articles/s41556-021-00641-w

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Understudied protein blobs have global effects on cell biochemistry
https://phys.org/news/2024-09-understudied-protein-blobs-global-effects.html
https://news.ycombinator.com/item?id=41602473

Biomolecular condensates regulate cellular electrochemical equilibria
https://www.cell.com/cell/abstract/S0092-8674(24)00909-7

#biology #biochemistry #electrochemistry #ProteinChemistry #BiomolecularCondensates #MolecularBiology #PhaseSeparation #PhaseLocalization #ProteinBlobs

A Newfound Source of Cellular Order in the Chemistry of Life
Inside cells, droplets of biomolecules called condensates merge, divide and dissolve
Their dance may regulate vital processes
https://www.quantamagazine.org/a-newfound-source-of-cellular-order-in-the-chemistry-of-life-20210107

#biology #biochemistry #ProteinChemistry #BiomolecularCondensates #MolecularBiology #PhaseSeparation #PhaseLocalization #ProteinDroplets

[thread] Biomolecular condensates
https://en.wikipedia.org/wiki/Biomolecular_condensate

* biochemistry - biomolecular condensate: membrane-less subcellular domains
* specialized cellular functions
* composition not controlled by bounding membrane
* form/maintain organization by var. processes
* phase separation of proteins, RNA, biopolymers into colloidal emulsions, gels, liquid crystals, solid crystals, aggregates

#biochemistry #ProteinChemistry #BiomolecularCondensates #PhaseSeparation #PhaseLocalization #ProteinDroplets

MolPhase:
Yansong Miao and colleagues present an advanced algorithm for predicting #phaseseparation propensities of proteins - and apply it to phytobacterial type III effectors
https://www.embopress.org/doi/full/10.1038/s44318-024-00090-9

In developing #presynapses, the #ActiveZone structure assembles via liquid-liquid #PhaseSeparation (#LLPS). This study shows that the #kinase SAD-1 phosphorylates the scaffold protein SYD-2/Liprin-α, relieving autoinhibition & triggering LLPS #PLOSBiology https://plos.io/3Ne6OZg

Studying the underlying molecular grammar of phase-separating systems.

The #Castaneda_lab shows that the N-terminal region of Ubiquilins is indispensable for distinct phase separation behaviour. #preprint

New preLight prepared by Aniruddha Das!

#preLight 👉 https://prelights.biologists.com/highlights/short-n-terminal-disordered-regions-and-the-proline-rich-domain-are-major-regulators-of-phase-transitions-for-full-length-ubqln1-ubqln2-and-ubqln4/

#PhaseSeparation #ubiquilins #biochemistry #biophysics

Fat droplets impact nucleus
https://www.sciencedaily.com/releases/2023/08/230828162352.htm

Small lipid droplets rigid enough to indent nucleus, dilute lamina, cause rupture
https://rupress.org/jcb/article-abstract/222/8/e202208123/214122/Small-lipid-droplets-are-rigid-enough-to-indent-a

* cytoplasmic fat-filled lipid droplets (FD) can indent, displace nucleus
* FD are phase-separated liquids w. a poorly understood interfacial tension

Phase separation a cellular compartmentalization, localization phenomenon
https://en.wikipedia.org/wiki/Biomolecular_condensate#Colloidal_phase_separation_theory

#CellBiology #MolecularBiology #LipidMetabolism #PhaseSeparation #organelles #biophysics

A very nice review on RNA granules from Geraldine Seydoux's lab at Genes & Development.

"RNA granules: functional compartments or incidental condensates?"

#RNA #granules #mRNA #phaseseparation #translation #splicing #Pbodies #StressGranules
#GermGranules

https://genesdev.cshlp.org/content/37/9-10/354.abstract

The final 'First person' interview in our current Issue is with Vaishna Vamadevan on her PhD project in Subbareddy Maddika's lab at Centre for DNA Fingerprinting and Diagnostics, Hyderabad, Telangana, India, investigating the role of ubiquitylation in regulating various cellular events:
https://journals.biologists.com/jcs/article/135/24/jcs260861/285952/First-person-Vaishna-Vamadevan
#cellbiology #research #ubiquitin #phaseseparation #science #sciencemastodon #earlycareerresearcher

Farias &co show that stress-induced phase separation of ERES components into Sec bodies precedes ER exit inhibition in mammalian cells. Initial peer review @ReviewCommons #openaccess: https://journals.biologists.com/jcs/article/135/23/jcs260294/285214/Stress-induced-phase-separation-of-ERES-components
#cellbiology #research #openscience #phaseseparation #ERstress

#Biomolecular #condensates and #PhaseSeparation are getting significant attention in the #signaling field. Here are two papers implicating condensates in #Hippo signaling. In the first, #cancer-initiating cells adopt a glycogen storing mode that blocks Hippo signaling through phase separation. In the second, antagonizing condensates control Hippo signaling without dissolution, via multiphase coalescence.
https://www.sciencedirect.com/science/article/pii/S0092867421011752
https://www.sciencedirect.com/science/article/pii/S0092867422012557