Lightnews — Scholar-powered news

Reposted by Aline Grata

Nisha Veits @nveits.bsky.social · 16d

How is developmental speed regulated ? 🪰

Happy to share my PhD story from Schweisguth Lab @devstempasteur.bsky.social. Here we show that cellular NAD+ availability and redox constrain developmental speed in the fly eye.

www.biorxiv.org/content/10.1...

A big thanks to everyone involved!

4 13 34

Aline Grata @alinegrata.bsky.social · Jul 4

Check out my first #preLight on the work of Sokol's team exploring PCP and mechanosensation! It was so much fun to pick a preprint, read it, write about it, and even get to ask the authors questions directly. I have a feeling this is just the beginning of many more preLight posts to come! 🙌

preLights @prelights.bsky.social · Jul 4

Stretch it, wound it, pull it: ADIP-Diversin polarizes anyway. Characterization of a new mechanosensitive polarity module 🐸

First #preLight from @alinegrata.bsky.social, highlighting #preprint from Chih-Wen Chu, Satheeja Velayudhan, Sergei Sokol and team:
prelights.biologists.com/highlights/m...

Mechanical cues organize planar cell polarity during vertebrate morphogenesis and embryonic wound repair - preLights

Stretch it, wound it, pull it: ADIP-Diversin polarizes anyway. Characterization of a new mechanosensitive polarity module.

prelights.biologists.com

5 14

Reposted by Aline Grata

epithelial mechanics fan club @epimechfc.bsky.social · Jun 29

Epithelial morphogenesis is all about how epithelial tissues develop unique shapes and structures! I'm @nehaghosh.bsky.social and will share some research in this area.

1 11 32

Aline Grata @alinegrata.bsky.social · May 21

This project was definitely a joint effort by multiple people. A huge thank you to all the members of Brian Mitchell’s lab at Northwestern University, and a very special thank you to the other co-first authors, Jennifer Sheridan and Julia Dorr!

Aline Grata @alinegrata.bsky.social · May 21

Our work suggests that although AK7 localizes at cilia, it has a non-ciliary function too, related to centriole maturation. We propose that the centriolar defects underlie much of the reduction in cilia number, contributing to the loss of mucociliary flow in AK7-depleted tissues, indicative of PCD.

1

Aline Grata @alinegrata.bsky.social · May 21

We observed that AK7 depletion leads to defects in centriole docking, with centrioles remaining sub-apical and therefore failing to nucleate motile cilia.

1

Aline Grata @alinegrata.bsky.social · May 21

The mechanism? Centrioles!
Cilia are anchored to the apical surface of MCCs via 150-200 centrioles, also known as basal bodies. These structures are generated close to the nucleus and then migrate apically, where they dock at the cell surface and subsequently give rise to cilia.

1

Aline Grata @alinegrata.bsky.social · May 21

We also performed SEM imaging and observed that ciliary structures are impaired when AK7 is lacking, with reductions in both cilia number and length.

1

Aline Grata @alinegrata.bsky.social · May 21

Loss of AK7 was related to PCD-like phenotypes, with decreased fluid flow and reduced beat frequency of MCCs. One of the challenges was to find a way to visualize live ciliary beating with a good enough spatiotemporal resolution (tipically cilia are around 15μm long with beating frequency of 15Hz).

2 1

Aline Grata @alinegrata.bsky.social · May 21

Primary ciliary dyskinesia (PCD) is a condition characterized by impaired mucociliary flow. Mutations in the AK7 gene have been found in patients, but AK7’s role in flow was unclear. We investigated this matter in flow-generating multiciliated cells (MCCs) in the skin epithelium of Xenopus embryos.

1 1

Aline Grata @alinegrata.bsky.social · May 21

Super excited to share that the final version of our study on the role of Adenylate Kinase 7 (AK7) on centriole maturation is finally out!

@devbiol.bsky.social

Read the full version here:
www.sciencedirect.com/science/arti...

Centriolar defects underlie a primary ciliary dyskinesia phenotype in an adenylate kinase 7 deficient ciliated epithelium

The skin of Xenopus embryos contains numerous multiciliated cells (MCCs), which collectively generate a directed fluid flow across the epithelial surf…

www.sciencedirect.com

1 4 9

Aline Grata @alinegrata.bsky.social · May 21

This project was definitely a joint effort by multiple people. A huge thank you to all the members of Brian Mitchell’s lab at Northwestern University, and a very special thank you to the other co-first authors, Jennifer Sheridan and Julia Dorr!

Aline Grata @alinegrata.bsky.social · May 21

Our work suggests that although AK7 localizes at cilia, it has a non-ciliary function too, related to centriole maturation.
We propose that the centriolar defects underlie much of the reduction in cilia number, contributing to the loss of mucociliary flow in AK7-depleted tissues, indicative of PCD.

1

Aline Grata @alinegrata.bsky.social · May 21

We observed that AK7 depletion leads to defects in centriole docking, with centrioles remaining sub-apical and therefore failing to nucleate motile cilia.

1

Aline Grata @alinegrata.bsky.social · May 21

The mechanism? Centrioles!
Cilia are anchored to the apical surface of MCCs via 150-200 centrioles, also known as basal bodies. These structures are generated close to the nucleus and then migrate apically, where they dock at the cell surface and subsequently give rise to cilia.

1

Aline Grata @alinegrata.bsky.social · May 21

We also performed SEM imaging and observed that ciliary structures are impaired when AK7 is lacking, with reductions in both cilia number and length.

1

Aline Grata @alinegrata.bsky.social · May 21

Loss of AK7 was related to PCD-like phenotypes, with decreased fluid flow and reduced beat frequency of MCCs. One of the challenges was to find a way to visualize live ciliary beating with a good enough spatiotemporal resolution (tipically cilia are around 15μm long with beating frequency of 15Hz).

1

Aline Grata @alinegrata.bsky.social · May 21

Primary ciliary dyskinesia (PCD) is a condition characterized by impaired mucociliary flow. Mutations in the AK7 gene have been found in patients, but AK7’s role in flow was unclear. We investigated this matter in flow-generating multiciliated cells (MCCs) in the skin epithelium of Xenopus embryos.

1 1

Reposted by Aline Grata

Tom Cumming @tomcumming.bsky.social · May 21

The effector caspases drive cell death, but their activation can often be survived, so how do cells make this decision? Our new preprint from @levayerr.bsky.social shows that instantaneous caspase activity is important, but past activation has a key role to play!

www.biorxiv.org/content/10.1...

1 14 29

Reposted by Aline Grata

Piplettes Magazine @piplettesmagazine.bsky.social · May 9

New article alert!

Ever met someone who looks exactly like you? Science says it’s more than a coincidence!

Read more on the science of look alikes in our latest piece, written by Silvia, PhD student in epigenetics🧬

www.piplettes-pasteur.com/post/you-may...

You may have a twin and you don’t know it: the science of look-alikes

Perhaps someone has already told you that you look like someone else, but is it actually true? It is! Science suggests that there is someone in the world that looks like you and that even shares your ...

www.piplettes-pasteur.com

1 4 10

Reposted by Aline Grata

Journal of Cell Science @jcellsci.bsky.social · Apr 28

In their Cell Science at a Glance article, @alinegrata.bsky.social & @levayerr.bsky.social @pasteur.fr describe the remodelling steps that take place within dying or extruding cells, outlining the commonalities & variations between tissues &organisms.
journals.biologists.com/jcs/article/...

Epithelial cell extrusion at a glance Icon for The Forest of Biologists
In collection: Adhesion , Cytoskeleton , Mechanobiology
Aline Grata, Romain Levayer

7 12

Aline Grata @alinegrata.bsky.social · Apr 24

We tried to cover everything we could - from the overall dynamics of extrusion, to the junction remodeling it requires, until the tissue-scale regulations and its physiological and clinical implications.

…I might be biased, but how fascinating is it to see how much there is still to discover?🤩

2

Aline Grata @alinegrata.bsky.social · Apr 24

So happy to share that our review on epithelial cell extrusion is out! @levayerr.bsky.social

Extrusion is such a plastic, context-dependent process, so capturing it visually in the poster that accompanies the article was a super challenging but fun task!

journals.biologists.com/jcs/article/...

Epithelial cell extrusion at a glance

Summary: Cell extrusion is a conserved process that leads to seamless expulsion of epithelial cells from tissues. This Cell Science at a Glance describes the functions and underlying mechanisms of cel...

journals.biologists.com

1 7 11

Reposted by Aline Grata

Levayer Lab @levayerr.bsky.social · Apr 24

Everything you always wanted to know about cell extrusion in one poster...check out this nice visual piece from @alinegrata.bsky.social and the accompanying review in this "at a glance" piece of @jcellsci.bsky.social

journals.biologists.com/jcs/article/...

Epithelial cell extrusion at a glance

Summary: Cell extrusion is a conserved process that leads to seamless expulsion of epithelial cells from tissues. This Cell Science at a Glance describes the functions and underlying mechanisms of cel...

journals.biologists.com

2 10 28

Aline Grata @alinegrata.bsky.social · Mar 25

Just wrapped up an amazing 2-week Principles and Applications of Fluorescent Microscopy #PAFM course @pasteur.fr!

Built a microscope, designed a confocal, attended great talks, and got hands-on with the latest tech🔬💡

Great mix of theory and practice. 10/10, highly recommend!🤩

#microscopy #biology

2 10