The lab is on a roll. 2nd preprint in as many weeks!
High levels of Cdc42 GTPase underlie an all-or-none decision to fuse.
Great team effort led by PhD students @sajjitasaha.bsky.social and @aiswaryasajeevan.bsky.social
www.biorxiv.org/content/10.1...
@biology-unige.bsky.social
High levels of Cdc42 GTPase underlie an all-or-none decision to fuse.
Great team effort led by PhD students @sajjitasaha.bsky.social and @aiswaryasajeevan.bsky.social
www.biorxiv.org/content/10.1...
@biology-unige.bsky.social
High levels of Cdc42 GTPase underlie an all-or-none decision to fuse
Cdc42 is a Rho-family GTPase conserved across eukaryotes, where it plays essential roles in cell polarization. In single-celled yeast systems, Cdc42 is a key driver of symmetry breaking and polarized ...
www.biorxiv.org
May 6, 2025 at 11:20 AM
The lab is on a roll. 2nd preprint in as many weeks!
High levels of Cdc42 GTPase underlie an all-or-none decision to fuse.
Great team effort led by PhD students @sajjitasaha.bsky.social and @aiswaryasajeevan.bsky.social
www.biorxiv.org/content/10.1...
@biology-unige.bsky.social
High levels of Cdc42 GTPase underlie an all-or-none decision to fuse.
Great team effort led by PhD students @sajjitasaha.bsky.social and @aiswaryasajeevan.bsky.social
www.biorxiv.org/content/10.1...
@biology-unige.bsky.social
RhoG, Rac1 and Cdc42 cooperation in cell protrusion revealed by multiplexed optogenetics and biosensor imaging by Klaus M. Hahn and team: www.biorxiv.org/content/10.6...
May 18, 2026 at 11:59 AM
RhoG, Rac1 and Cdc42 cooperation in cell protrusion revealed by multiplexed optogenetics and biosensor imaging by Klaus M. Hahn and team: www.biorxiv.org/content/10.6...
Polarized growth in #Spombe needs Cdc42, but what role does it play in cell fusion? @sajjitasaha.bsky.social @sophiemartinlab.bsky.social &co show that mitotic polarized growth responds linearly to Cdc42 levels, but mating involves a sharp switch-like response @plosbiology.org 🧪 plos.io/4bvGIhb
March 20, 2026 at 2:05 PM
Polarized growth in #Spombe needs Cdc42, but what role does it play in cell fusion? @sajjitasaha.bsky.social @sophiemartinlab.bsky.social &co show that mitotic polarized growth responds linearly to Cdc42 levels, but mating involves a sharp switch-like response @plosbiology.org 🧪 plos.io/4bvGIhb
A trio of new #ScienceImmunology studies demonstrates how CDC42 regulates the activation of the innate immune sensor pyrin and characterizes mutations that underlie autoinflammatory disorders in humans.
📃: https://scim.ag/3RvXbe4
📃: https://scim.ag/3RvXbuA
📃: https://scim.ag/4fGVsM7
📃: https://scim.ag/3RvXbe4
📃: https://scim.ag/3RvXbuA
📃: https://scim.ag/4fGVsM7
August 11, 2026 at 3:00 PM
A trio of new #ScienceImmunology studies demonstrates how CDC42 regulates the activation of the innate immune sensor pyrin and characterizes mutations that underlie autoinflammatory disorders in humans.
📃: https://scim.ag/3RvXbe4
📃: https://scim.ag/3RvXbuA
📃: https://scim.ag/4fGVsM7
📃: https://scim.ag/3RvXbe4
📃: https://scim.ag/3RvXbuA
📃: https://scim.ag/4fGVsM7
The August 2026 issue of #ScienceImmunology is out!
This month's cover depicts the innate sensor pyrin interacting with the small GTPase CDC42, highlighting recent findings that could shed light on autoinflammatory disorders.
Learn about this research and more: https://scim.ag/3TvM4Cx
This month's cover depicts the innate sensor pyrin interacting with the small GTPase CDC42, highlighting recent findings that could shed light on autoinflammatory disorders.
Learn about this research and more: https://scim.ag/3TvM4Cx
August 10, 2026 at 9:00 PM
The August 2026 issue of #ScienceImmunology is out!
This month's cover depicts the innate sensor pyrin interacting with the small GTPase CDC42, highlighting recent findings that could shed light on autoinflammatory disorders.
Learn about this research and more: https://scim.ag/3TvM4Cx
This month's cover depicts the innate sensor pyrin interacting with the small GTPase CDC42, highlighting recent findings that could shed light on autoinflammatory disorders.
Learn about this research and more: https://scim.ag/3TvM4Cx
New paper out in EMBO Reports!
We show that Cdc42 regulation is oligomerization-dependent and that a GEF and a GAP act synergistically: Cdc24 relieves self-inhibition of oligomeric Rga2, enabling robust Cdc42 cycling.
doi.org/10.1038/s44319-026-00695-7
#cellpolarity #Cdc42 #synergy #syntheticbiology
We show that Cdc42 regulation is oligomerization-dependent and that a GEF and a GAP act synergistically: Cdc24 relieves self-inhibition of oligomeric Rga2, enabling robust Cdc42 cycling.
doi.org/10.1038/s44319-026-00695-7
#cellpolarity #Cdc42 #synergy #syntheticbiology
Oligomerization-dependent and synergistic regulation of Cdc42 GTPase cycling by a GEF and a GAP - EMBO Reports
Cell polarity is a crucial biological process essential for cell division, directed growth, and motility. In Saccharomyces cerevisiae, polarity establishment centers around the small Rho-type GTPase C...
doi.org
February 22, 2026 at 6:26 PM
New paper out in EMBO Reports!
We show that Cdc42 regulation is oligomerization-dependent and that a GEF and a GAP act synergistically: Cdc24 relieves self-inhibition of oligomeric Rga2, enabling robust Cdc42 cycling.
doi.org/10.1038/s44319-026-00695-7
#cellpolarity #Cdc42 #synergy #syntheticbiology
We show that Cdc42 regulation is oligomerization-dependent and that a GEF and a GAP act synergistically: Cdc24 relieves self-inhibition of oligomeric Rga2, enabling robust Cdc42 cycling.
doi.org/10.1038/s44319-026-00695-7
#cellpolarity #Cdc42 #synergy #syntheticbiology
Cdc42 coordinates PDGFRb+ Mural Cell migration proliferation morphogenesis (wrapping filopodia) during postanatal retinal #Angiogenesis👁️
PDGFRb+ mural cell Cdc42 KO🐭➡️
⏫Angiogenic front leakage
⏬Tip cell filopodia
Perturbed arterial patterning
#VasPharma 2025
www.sciencedirect.com/science/arti...
PDGFRb+ mural cell Cdc42 KO🐭➡️
⏫Angiogenic front leakage
⏬Tip cell filopodia
Perturbed arterial patterning
#VasPharma 2025
www.sciencedirect.com/science/arti...
March 25, 2025 at 8:11 PM
Cdc42 coordinates PDGFRb+ Mural Cell migration proliferation morphogenesis (wrapping filopodia) during postanatal retinal #Angiogenesis👁️
PDGFRb+ mural cell Cdc42 KO🐭➡️
⏫Angiogenic front leakage
⏬Tip cell filopodia
Perturbed arterial patterning
#VasPharma 2025
www.sciencedirect.com/science/arti...
PDGFRb+ mural cell Cdc42 KO🐭➡️
⏫Angiogenic front leakage
⏬Tip cell filopodia
Perturbed arterial patterning
#VasPharma 2025
www.sciencedirect.com/science/arti...
Our paper is out in ACS Synthetic Biology!!
A major bottleneck in reconstituting cell polarity is obtaining functional prenylated Cdc42. Here, we developed a Sortase-based strategy to farnesylate Cdc42, which retains membrane binding and regulatory GTPase activity.
doi.org/10.1021/acss...)
A major bottleneck in reconstituting cell polarity is obtaining functional prenylated Cdc42. Here, we developed a Sortase-based strategy to farnesylate Cdc42, which retains membrane binding and regulatory GTPase activity.
doi.org/10.1021/acss...)
May 19, 2026 at 5:23 AM
Our paper is out in ACS Synthetic Biology!!
A major bottleneck in reconstituting cell polarity is obtaining functional prenylated Cdc42. Here, we developed a Sortase-based strategy to farnesylate Cdc42, which retains membrane binding and regulatory GTPase activity.
doi.org/10.1021/acss...)
A major bottleneck in reconstituting cell polarity is obtaining functional prenylated Cdc42. Here, we developed a Sortase-based strategy to farnesylate Cdc42, which retains membrane binding and regulatory GTPase activity.
doi.org/10.1021/acss...)
Polarized growth in #Spombe needs Cdc42, but what role does it play in cell fusion? @sajjitasaha.bsky.social @sophiemartinlab.bsky.social &co show that mitotic polarized growth responds linearly to Cdc42 levels, but mating involves a sharp switch-like response @plosbiology.org 🧪 plos.io/4bvGIhb
March 20, 2026 at 5:35 PM
Polarized growth in #Spombe needs Cdc42, but what role does it play in cell fusion? @sajjitasaha.bsky.social @sophiemartinlab.bsky.social &co show that mitotic polarized growth responds linearly to Cdc42 levels, but mating involves a sharp switch-like response @plosbiology.org 🧪 plos.io/4bvGIhb
Sometimes, knocking out a gene isn't a good way to figure out the function of that gene ...
In our new @jcellsci.bsky.social paper, we report potent transcriptional adaptation by cytotoxic T lymphocytes (CTLs) in response to CRISPR/Cas9-mediated deletion of the important polarity protein CDC42 🧵⬇️
In our new @jcellsci.bsky.social paper, we report potent transcriptional adaptation by cytotoxic T lymphocytes (CTLs) in response to CRISPR/Cas9-mediated deletion of the important polarity protein CDC42 🧵⬇️
August 4, 2025 at 7:31 PM
Sometimes, knocking out a gene isn't a good way to figure out the function of that gene ...
In our new @jcellsci.bsky.social paper, we report potent transcriptional adaptation by cytotoxic T lymphocytes (CTLs) in response to CRISPR/Cas9-mediated deletion of the important polarity protein CDC42 🧵⬇️
In our new @jcellsci.bsky.social paper, we report potent transcriptional adaptation by cytotoxic T lymphocytes (CTLs) in response to CRISPR/Cas9-mediated deletion of the important polarity protein CDC42 🧵⬇️
Distinct #Cdc42 protein levels differentially regulate polarized growth and cell fusion in Schizosaccharomyces pombe
The work of @sajjitasaha.bsky.social and @aiswaryasajeevan.bsky.social, with Laura Merlini and Vincent Vincenzetti, now out in @plosbiology.org !
@biology-unige.bsky.social
The work of @sajjitasaha.bsky.social and @aiswaryasajeevan.bsky.social, with Laura Merlini and Vincent Vincenzetti, now out in @plosbiology.org !
@biology-unige.bsky.social
Polarized growth in #Spombe needs Cdc42, but what role does it play in cell fusion? @sajjitasaha.bsky.social @sophiemartinlab.bsky.social &co show that mitotic polarized growth responds linearly to Cdc42 levels, but mating involves a sharp switch-like response @plosbiology.org 🧪 plos.io/4bvGIhb
March 22, 2026 at 10:39 AM
Distinct #Cdc42 protein levels differentially regulate polarized growth and cell fusion in Schizosaccharomyces pombe
The work of @sajjitasaha.bsky.social and @aiswaryasajeevan.bsky.social, with Laura Merlini and Vincent Vincenzetti, now out in @plosbiology.org !
@biology-unige.bsky.social
The work of @sajjitasaha.bsky.social and @aiswaryasajeevan.bsky.social, with Laura Merlini and Vincent Vincenzetti, now out in @plosbiology.org !
@biology-unige.bsky.social
If you're interested in the factors that enable the regular structure of CNS #myelin sheaths by #oligodendrocytes, check this out. Featuring a #CDC42 - effector proteins - #septin axis. Congrats to 1st author Sophie, and a big thank you to all who contributed
onlinelibrary.wiley.com/doi/10.1002/...
onlinelibrary.wiley.com/doi/10.1002/...
CDC42‐Effector Proteins Regulate Higher Order Structure of Septins Required for CNS Myelin Integrity
CDC42-effector proteins 1/2 are present in CNS myelin.
They facilitate the higher order structure of myelin septin filaments.
Their loss impairs septin-dependent scaffolding of myelin.
Myelin o...
onlinelibrary.wiley.com
February 2, 2026 at 9:40 AM
If you're interested in the factors that enable the regular structure of CNS #myelin sheaths by #oligodendrocytes, check this out. Featuring a #CDC42 - effector proteins - #septin axis. Congrats to 1st author Sophie, and a big thank you to all who contributed
onlinelibrary.wiley.com/doi/10.1002/...
onlinelibrary.wiley.com/doi/10.1002/...
Excited to share our latest work linking Cdc42 waves to mitotic cell size sensing and spindle length.
www.science.org/doi/10.1126/...
www.science.org/doi/10.1126/...
June 26, 2026 at 7:47 PM
Excited to share our latest work linking Cdc42 waves to mitotic cell size sensing and spindle length.
www.science.org/doi/10.1126/...
www.science.org/doi/10.1126/...
Cdc42 is a small GTPase crucial for #CellPolarity, but how does it contribute to #aging when upregulated? This study shows that the ER-anchored chaperone Ydj1 interacts with Cdc42, enhancing its stability & partitioning during asymm #CellDivision & aging in yeast @plosbiology.org 🧪 plos.io/4qz7WaM
February 13, 2026 at 5:35 PM
Cdc42 is a small GTPase crucial for #CellPolarity, but how does it contribute to #aging when upregulated? This study shows that the ER-anchored chaperone Ydj1 interacts with Cdc42, enhancing its stability & partitioning during asymm #CellDivision & aging in yeast @plosbiology.org 🧪 plos.io/4qz7WaM
In a recent #ASNJASN article, authors report that ephrin-B1 at slit diaphragm suppresses cdc42 activity by preventing the interaction of Par6 with cdc42 and functions to keep the specialized phenotype of podocytes. Read more: kidney.pub/JASN0728 #BasicResearch
July 20, 2025 at 4:00 PM
In a recent #ASNJASN article, authors report that ephrin-B1 at slit diaphragm suppresses cdc42 activity by preventing the interaction of Par6 with cdc42 and functions to keep the specialized phenotype of podocytes. Read more: kidney.pub/JASN0728 #BasicResearch
chromatin→cortex axis is likely multi-step: chromatin proximity builds a Ran-GTP/Cdc42 polarity cue, and Fyn may gate/amplify local outputs. Downstream suspects include Cdc42–N/WASP→Arp2/3, formins (mDia), pERM, and myosin-II via MRCK/ROCK. #ESHREjc
January 30, 2026 at 4:46 PM
chromatin→cortex axis is likely multi-step: chromatin proximity builds a Ran-GTP/Cdc42 polarity cue, and Fyn may gate/amplify local outputs. Downstream suspects include Cdc42–N/WASP→Arp2/3, formins (mDia), pERM, and myosin-II via MRCK/ROCK. #ESHREjc
Three articles in @sciimmunology.bsky.social describe the molecular mechanisms by which pyrin is hyperactivated, where CDC42 is a binding partner of the pyrin B30.2 domain
www.science.org/doi/10.1126/...
www.science.org/doi/10.1126/...
August 7, 2026 at 8:06 PM
Three articles in @sciimmunology.bsky.social describe the molecular mechanisms by which pyrin is hyperactivated, where CDC42 is a binding partner of the pyrin B30.2 domain
www.science.org/doi/10.1126/...
www.science.org/doi/10.1126/...
Happy Mardi Gras from the Ogden Lab! This is a confocal micrograph of MEF cells wearing their Mardi Gras colors! Nuclei - yellow; Cdc42 - green; Membrane protein - purple. Image from St. Jude grad student @christinaadaly.bsky.social 🧪 👩🔬 🔬
February 13, 2024 at 5:15 PM
Happy Mardi Gras from the Ogden Lab! This is a confocal micrograph of MEF cells wearing their Mardi Gras colors! Nuclei - yellow; Cdc42 - green; Membrane protein - purple. Image from St. Jude grad student @christinaadaly.bsky.social 🧪 👩🔬 🔬
Membrane curvature initiates Cdc42-FBP17-N-WASP clustering and actin nucleation
Yansong Miao and coworkers
link.springer.com/article/10.1...
Yansong Miao and coworkers
link.springer.com/article/10.1...
Membrane curvature initiates Cdc42-FBP17-N-WASP clustering and actin nucleation - The EMBO Journal
The architecture of actin networks at the cell surface is regulated by local membrane topology. However, how actin nucleation can respond sensitively to the degree of membrane curvature remains incomp...
link.springer.com
January 5, 2026 at 7:40 AM
Membrane curvature initiates Cdc42-FBP17-N-WASP clustering and actin nucleation
Yansong Miao and coworkers
link.springer.com/article/10.1...
Yansong Miao and coworkers
link.springer.com/article/10.1...
Cdc42 is a small GTPase crucial for #CellPolarity, but how does it contribute to #aging when upregulated? This study shows that the ER-anchored chaperone Ydj1 interacts with Cdc42, enhancing its stability & partitioning during asymm #CellDivision & aging in yeast @plosbiology.org 🧪 plos.io/4qz7WaM
February 16, 2026 at 9:05 AM
Cdc42 is a small GTPase crucial for #CellPolarity, but how does it contribute to #aging when upregulated? This study shows that the ER-anchored chaperone Ydj1 interacts with Cdc42, enhancing its stability & partitioning during asymm #CellDivision & aging in yeast @plosbiology.org 🧪 plos.io/4qz7WaM
. @adamrochussen.bsky.social, Claire Ma & Gillian Griffiths @griffithslab.bsky.social find that deletion of Cdc42 in primary T cells triggers transcriptional adaptation, leading to enhanced T cell function.
journals.biologists.com/jcs/article/...
Article: journals.biologists.com/jcs/article/...
journals.biologists.com/jcs/article/...
Article: journals.biologists.com/jcs/article/...
August 11, 2025 at 10:56 AM
. @adamrochussen.bsky.social, Claire Ma & Gillian Griffiths @griffithslab.bsky.social find that deletion of Cdc42 in primary T cells triggers transcriptional adaptation, leading to enhanced T cell function.
journals.biologists.com/jcs/article/...
Article: journals.biologists.com/jcs/article/...
journals.biologists.com/jcs/article/...
Article: journals.biologists.com/jcs/article/...
Cdc42 is a small GTPase crucial for #CellPolarity, but how does it contribute to #aging when upregulated? This study shows that the ER-anchored chaperone Ydj1 interacts with Cdc42, enhancing its stability & partitioning during asymm #CellDivision & aging in yeast @plosbiology.org 🧪 plos.io/4qz7WaM
February 13, 2026 at 2:05 PM
Cdc42 is a small GTPase crucial for #CellPolarity, but how does it contribute to #aging when upregulated? This study shows that the ER-anchored chaperone Ydj1 interacts with Cdc42, enhancing its stability & partitioning during asymm #CellDivision & aging in yeast @plosbiology.org 🧪 plos.io/4qz7WaM
The surprise is that, over the same fold-change, cellular dimensions vary linearly with Cdc42 protein levels. So polarized growth has a linear relationship with Cdc42 levels.
➡️ Open question: How does this match with all the positive and negative feedback regulation that control Cdc42 activity?
➡️ Open question: How does this match with all the positive and negative feedback regulation that control Cdc42 activity?
May 6, 2025 at 11:20 AM
The surprise is that, over the same fold-change, cellular dimensions vary linearly with Cdc42 protein levels. So polarized growth has a linear relationship with Cdc42 levels.
➡️ Open question: How does this match with all the positive and negative feedback regulation that control Cdc42 activity?
➡️ Open question: How does this match with all the positive and negative feedback regulation that control Cdc42 activity?