Lightnews — Scholar-powered news

Reposted by Zoe Nahas

Marc Somssich @somssich.bsky.social · 4d

People: "Things used to be better."

Scientist: "When did it start getting worse?"

People: "When I was born."

From "The illusion of moral decline" by Adam Mastroianni.
shorturl.at/FFEDV

A graph showing violin plots. On the y axis is the perceived morality of people from 0 to 8. On the x axis the time points 40 years before my birth, 20 years before my birth, at my birth, 20 years past my birth, today. The morality value is constant until birth, and then declines.

7 9

Reposted by Zoe Nahas

Claudia Bank @cbank.bsky.social · 1d

Please spread the word! 10 days left to apply for this #sciencejobs as Assistant Professor Tenure Track in Quantitative Cell Biology 👩‍🔬
@izb-unibern.bsky.social @unibe.ch! ohws.prospective.ch/public/v1/jo...
#QueerInSTEM #DisabledInSTEM #BlackInSTEM #WomenInSTEM #CarersInSTEM #AcademicSky #HigherED

Uni Bern: Assistant Professor with tenure-track for Quantitative Cell Biology

Start date of employment: anticipated for August 2027

ohws.prospective.ch

20 20

Reposted by Zoe Nahas

Merissa Huei-Hsuan Tsai @hueihsuantsai.bsky.social · 6d

Very excited to see our @nikogeldner.bsky.social lab x Feng Zhou lab work featured on the cover of Science!
(1/5) We reveal how root architecture and nutrient leakage shape spatial patterns of microbial colonization, moving beyond traditional models of uniform exudation.

Science Magazine @science.org · 6d

Using precise spatial and temporal analysis, researchers in Science provide insight into how bacteria around the root interact both with the plant and with each other.

Learn more in this week's issue: https://scim.ag/3WgNajk

A confocal microscopy image shows root-colonizing bacteria clustering around an emerging lateral root, where localized glutamine leakage induces spatially confined reporter activity.

8 40 100

Reposted by Zoe Nahas

John Innes Centre @johninnescentre.bsky.social · 5d

VACANCY - Independent research fellowships leading to tenured positions

We’re inviting applications from outstanding researchers who either hold, or wish to apply for, Independent Research Fellowships.

APPLICATION DEADLINE: 10 November 2025

Click here to apply: jic.link/Fellows

1 27 18

Reposted by Zoe Nahas

nikogeldner.bsky.social @nikogeldner.bsky.social · 5d

A long road to the Cover of Science!
www.science.org/doi/10.1126/...

Localized glutamine leakage drives the spatial structure of root microbial colonization

Plant roots release exudates to encourage microbiome assembly, which influences the function and stress resilience of plants. How specific exudates drive spatial colonization patterns remains largely ...

www.science.org

9 49 130

Reposted by Zoe Nahas

Xander Jones @xanderjones.bsky.social · 5d

Only a few days left to apply!

My group is looking for a postdoc to engineer and deploy new tools to precisely manipulate and decode how auxin coordinates plant morphogenesis.

@starmorph-syg.bsky.social

Research Associate - Reprogramming Development (closes 7 October 2025)

www.cam.ac.uk

1 29 19

Reposted by Zoe Nahas

Hilde Schneemann @hildeschneemann.bsky.social · 10d

🚂 This petition needs your signatures! Save the wonderful nighttrain that gets you into the center of Paris/Vienna/Berlin in time for breakfast whilst you doze off or have memorable encounters and conversations with fellow travellers agir.greenvoice.fr/petitions/sa...

🚂 Sauvons les trains de nuit Paris-Berlin et Paris-Vienne

Signez la pétition maintenant !

agir.greenvoice.fr

5 4

Reposted by Zoe Nahas

Cristina Ferrándiz @cristicris.bsky.social · 27d

It was already known that auxins (surprise!) had a key role controlling the end of flowering, plant menopause. Now we can tell you how and where they act in the inflorescence meristem to control the process.
@irenegonzlez.bsky.social
www.cell.com/current-biology/fulltext/S0960-9822%2825%2901002-4

Local regulation of auxin-related pathways in the shoot apical meristem plays a major role during proliferative arrest

González-Cuadra et al. show that repression of auxin-related pathways locally in the SAM is key in the control of proliferative arrest. FRUITFULL regulates these pathways to promote meristem arrest. B...

www.cell.com

12 40

Zoe Nahas @zoenahas.bsky.social · 12d

Oh amazing @jamespblloyd.bsky.social, this makes me very happy to hear, so thank you! My PhD built very directly on previous work in the Leyser group, including Scott's :)

1 1

Zoe Nahas @zoenahas.bsky.social · 12d

Thanks Adrien!! @halloulab.bsky.social

1

Zoe Nahas @zoenahas.bsky.social · 12d

Thanks Jim! Hope you're well :)

Zoe Nahas @zoenahas.bsky.social · 12d

Check out the link below for a summary of our recent paper on how plants coordinate their branching architecture, via @slcuplants.bsky.social 🌱

Sainsbury Laboratory Cambridge University (SLCU) @slcuplants.bsky.social · 19d

🌱From Bud to Branch🌱
New model reveals how local & systemic signals combine to regulate shoot branching.
"...by modulating #auxin transport, local #BRC1 expression in each bud could contribute to the systemic control of branching." @zoenahas.bsky.social
🔗 dx.plos.org/10.1371/jour...
@plosbiology.org

Axillary buds are located at the base of each leaf. Initially dormant, each can grow into a branch. To study how branching is regulated by local signalling within each bud and by systemic signalling from other buds, we used stem sections with two axillary buds and their associated leaves (left). This signalling network influences, for example, whether one bud grows and rapidly inhibits the other (middle), or whether both buds grow simultaneously (right).

3 8

Zoe Nahas @zoenahas.bsky.social · 12d

TLDR: Combining experiments + modelling is really useful (& fun ✨) to generate and test hypotheses about multi-scale signal integration. We propose an integrated model of shoot branching regulation that accounts for the ability of buds to regulate the number + location of growing branches 16/16

1

Zoe Nahas @zoenahas.bsky.social · 12d

It's interesting that BRC1 is responsive to local environmental cues like light. Having local sensing relayed into a decentralised mode of regulation could enable flexible adjustment of branching to heterogenous environmental conditions while maintaining whole-plant coordination 15/n

1 1

Zoe Nahas @zoenahas.bsky.social · 12d

The overall point? We propose that BRC1 influences the competitive strength of each bud by tuning how easily buds export auxin, while systemic auxin transport balances growth of the whole shoot system 14/n

a tree with lots of green leaves is against a white background

ALT: a tree with lots of green leaves is against a white background

media.tenor.com

1 1

Zoe Nahas @zoenahas.bsky.social · 12d

We found that changing only the model parameter hypothesised to be BRC1 could predict largely accurately the effect of strigolactone on plants where PIN1 is insensitive to strigolactone (so where strigolactone is expected to act only/mostly through BRC1) 13/n

1 1

Zoe Nahas @zoenahas.bsky.social · 12d

Throughout, we could test the effect of strigolactone independent of BRC1 by applying strigolactone to a brc1 mutant, but we couldn't do the same with PIN1 given the pin1 mutant is pleiotropic & doesn't even form axillary buds. So we made a chimeric PIN1 with impaired sensitivity to strigolact 12/n

1

Zoe Nahas @zoenahas.bsky.social · 12d

By varying two parameters representing the effects of strigolactone on (i) BRC1 & (ii) PIN1, the model could capture the competition outcomes and growth dynamics of many different 2-node mutants with varying BRC1 levels, with or without altered PIN1 🕺 11/n

1 1

Zoe Nahas @zoenahas.bsky.social · 12d

So we built a mathematical model of interactions between 2 buds! As a simple self-activating and mutually-inhibiting system. If, as hypothesised, BRC1 affects background rate of bud auxin efflux, modifying this parameter in our model should reproduce the phenotypes of plants w/ altered BRC1 10/n

1 1 3

Zoe Nahas @zoenahas.bsky.social · 12d

We wondered, can these two hypotheses account for the wide range of bud-bud interactions we observe in different mutants/treatments? But with 2 buds, branching outcomes are an emergent property of local and bud-bud regulation, w/ regulatory interactions that are feedback-driven so non-intuitive..9/n

a woman is looking at a triangle with the equation a = 1b / h written on it .

ALT: a woman is looking at a triangle with the equation a = 1b / h written on it .

media.tenor.com

1

Zoe Nahas @zoenahas.bsky.social · 12d

In previous work (x.com/zoenahas/sta...) we hypothesised that in isolated buds (i) the initial slow-growing lag phase of bud growth corresponds to the time when buds establish canalised auxin transport (i.e., sustained auxin export) and (ii) BRC1 might regulate how long this takes 🤔 8/n

x.com

1

Zoe Nahas @zoenahas.bsky.social · 12d

Different scales of observation reveal different phenomena 🚨 When buds are alone (1-node), brc1 mutation always led to rapid bud growth, even if auxin transport was affected. But when buds are in the presence of another bud (2-node), both BRC1 + auxin transport mattered! How does this work? 7/n

1

Zoe Nahas @zoenahas.bsky.social · 12d

We used brc1 and strigolactone mutants to see how bud-bud interactions are affected by altered BRC1 expression with/without also altering auxin transport 6/n

1

Zoe Nahas @zoenahas.bsky.social · 12d

We used 1- and 2-node explants (stem segments with 1 or 2 buds) as minimal systems for studying the effect of bud-bud interactions. We already knew 2-nodes can show different outcomes: sometimes neither buds grow, only one bud grows and inhibits the other, or both grow, as illustrated below 5/n

1

Zoe Nahas @zoenahas.bsky.social · 12d

Our question: What is the interplay between local regulation via BRC1 and systemic regulation via auxin transport? We leveraged the fact that strigolactone affects both BRC1 expression and auxin transport to help us explore the relationship between these two hubs 4/n

1 1