Journal of Cell Biology

03/30/2022

Three interacting regions of the Ndc80 and Dam1 complexes support microtubule tip-coupling under load

Using laser trapping with recombinant Ndc80 and Dam1 kinetochore complexes, Rachel Flores, Charles Asbury, Trisha Davis and colleagues (University of Washington) show that interactions between three distinct regions of the complexes support strong, stable attachments to dynamic microtubule tips. Phosphorylating two of the regions reduces both attachment strength and stability. Phosphorylating the third region specifically reduces long-term stability.

Using laser trapping with recombinant Ndc80 and Dam1 kinetochore complexes, Flores et al. show that interactions between three distinct regions of the complexes

03/29/2022

New editorial board members

We're pleased to introduce the newest members of the JCB editorial board:
Gregory Alushin, Tamara Caspary, Çagla Eroglu, Andrew Ewald, Laura Lackner, Michael Lazarou, Kassandra Ori-McKenney, Tatiana Petrova, Elçin Ünal, Sara Wickström, and Bo Zhong.
We are grateful to these and all of our board members for their contributions to JCB and service to the cell biology community.

We are pleased to introduce the newest members of the JCB editorial board. We are grateful to these and all of our board members for their contributions to JCB

03/28/2022

PD-LI promotes rear retraction during persistent cell migration by altering integrin β4 dynamics

Mengdie Wang, Choua Xiong and Arthur M. Mercurio (UMass Chan Medical School) reveal an unexpected cell-intrinsic function of PD-L1 in regulating the dynamics of the plasma membrane that facilitates persistent cell migration. The study highlights the diverse processes that PD-L1 can regulate independently of its immune checkpoint function.

This study reveals an unexpected cell-intrinsic function of PD-L1 in regulating the dynamics of the plasma membrane that facilitates persistent cell migration.

03/28/2022

Non-canonical ubiquitylation makes its mark on Rap2 and cell motility

Patrick Caswell (The University of Manchester) previews work from Duncan et al. (https://bit.ly/3qdQtbx) which characterizes the mechanism by which Rab40b/Cul5 ubiquitylation of Rap2 controls its activity and correct localization during cell migration.

Patrick Caswell previews work from Duncan et al. which characterizes the mechanism by which Rab40b/Cul5 ubiquitylation of Rap2 controls its activity and correct

03/25/2022

Dia1 coordinates differentiation and cell sorting in a stratified epithelium

Robert M. Harmon, John Devany and Margaret L. Gardel (University of Chicago Physics) demonstrate that differential expression of an actin nucleator, the formin Dia1, drives cell sorting and maintains distinct morphological domains within an epithelial tissue. This illuminates the possible utility of the large formin family in orchestrating the compartmentalization and differentiation of complex tissues.

Harmon et al. demonstrate that differential expression of an actin nucleator, the formin, Dia1, drives cell sorting and maintains distinct morphological domains

03/25/2022

Clathrin coated pits as signaling platforms for Akt signaling

In this new Spotlight, Liz Smythe (The University of Sheffield) highlights work from the Antonescu lab (https://bit.ly/3vBdf0K) showing how clathrin coated pits segregate a subset of Akt signaling.

Liz Smythe highlights work from the Antonescu lab showing how clathrin coated pits segregate a subset of Akt signalling.

03/24/2022

Local regulation of extracellular vesicle traffic by the synaptic endocytic machinery

Cassandra R. Blanchette, Amy L. Scalera, Avital A. Rodal and colleagues (Brandeis University) show a novel role for the endocytic machinery in regulating extracellular vesicle (EV) trafficking at Drosophila neuromuscular synapses. In endocytic mutants, EV cargoes are missorted and then removed from the synapse by retrograde transport, leading to disruption of their physiological functions.

Blanchette and Scalera et al. show a novel role for the endocytic machinery in regulating extracellular vesicle (EV) trafficking at Drosophila neuromuscular syn

03/24/2022

Tweaking neural organoids to model human reactive astrocytes

Paola Bezzi (Université de Lausanne) previews work from Cvetkovic et al. (https://bit.ly/3uBOAsl) that presents a neural organoid system to model human reactive astrocytes.

Bezzi previews work from Cvetkovic et al. that presents a neural organoid system to model human reactive astrocytes.

03/23/2022

Ori Avinoam: Mind, body, and membranes in shape

Ori Avinoam (Weizmann Institute of Science) studies membrane remodeling with a focus on cell-to-cell fusion through the lens of correlative light and electron microscopy. In our latest People and Ideas series, we chatted with Ori about his scientific journey and future research plans.

Ori Avinoam studies membrane remodeling with a focus on cell-to-cell fusion through the lens of correlative light and electron microscopy.

03/23/2022

mTORC2 suppresses cell death induced by hypo-osmotic stress by promoting sphingomyelin transport

Yumiko Ono, Kenji Matsuzawa and Junichi Ikenouchi (Kyushu University 代謝生理学研究室) revealed that mTORC2–Rab35 activation by hypo-osmotic stress not only promotes apical transport of sphingomyelin to supply membrane but also decreases the actin cortex underlining the apical membrane by reducing PI(4,5)P2 to facilitate the expansion of the apical membrane.

Ono et al. revealed that mTORC2–Rab35 activation by hypo-osmotic stress not only promotes apical transport of sphingomyelin to supply membrane but also decrease

03/17/2022

JAM-A–tetraspanin–αvβ5 integrin complex regulates contact inhibition of locomotion

Contact inhibition of locomotion is a process that regulates cell motility upon cell collision. Kummer, Steinbacher, Thölmann, Ebnet (WWU Münster - Münster University) and colleagues show that JAM-A inhibits the activity of the Src–Erk1/2 pathway and of Rac1 to stabilize cell matrix adhesions and to inhibit protrusive activity upon contact formation.

Contact inhibition of locomotion is a process that regulates cell motility upon cell collision. Kummer et al. show that JAM-A inhibits the activity of the Src–E

03/16/2022

Ubiquitylation by Rab40b/Cul5 regulates Rap2 localization and activity during cell migration

The Rab40b/Cul5 complex is an emerging pro-migratory molecular machine. Emily D. Duncan, Rytis Prekeris and colleagues (University of Colorado Anschutz Medical Campus) demonstrate that Rab40b/Cul5 ubiquitylates Rap2 to regulate its localization and activity, ultimately proposing a model by which Rap2 is targeted to the leading-edge plasma membrane to regulate actin dynamics during cell migration.

The Rab40b/Cul5 complex is an emerging pro-migratory molecular machine. Duncan et al. demonstrate that Rab40b/Cul5 ubiquitylates Rap2 to regulate its localizati

03/16/2022

Material properties of phase-separated TFEB condensates regulate the autophagy-lysosome pathway

Protein condensates possess distinct material properties. Zheng Wang, Hong Zhang and colleagues (Institute of Biophysics, CAS) show that the material properties of TFEB condensates govern their size and transcriptional activity. These properties can be manipulated to modulate the activity of TFEB in the autophagy-lysosome pathway.

Protein condensates possess distinct material properties. Wang et al. show that the material properties of TFEB condensates govern their size and transcriptiona

03/15/2022

Prion-like domains drive CIZ1 assembly formation at the inactive X chromosome | Journal of Cell Biology | Rockefeller University Press

Sajad Sofi, Dawn Coverley (University of York) and colleagues dissect the requirement for glutamine-rich prion-like domains in the formation of intranuclear CIZ1 protein assemblies at the inactive X chromosome. This study highlights the influence of alternative splicing and implicates a polyglutamine domain in maintenance of the epigenetic state.

This paper dissects the requirement for glutamine-rich prion-like domains in the formation of intranuclear CIZ1 protein assemblies at the inactive X chromosome.

03/10/2022

The E3 ligase TRIM1 ubiquitinates LRRK2 and controls its localization, degradation, and toxicity | Journal of Cell Biology | Rockefeller University Press

Adrienne E.D. Stormo, Scott A. Oakes, Annie Hiniker (UC San Diego) and colleagues use a quantitative mass spectrometry–based approach to identify the microtubule-associated E3 ubiquitin ligase TRIM1 as a novel interacting partner of the Parkinson’s disease–driving kinase LRRK2. They find that TRIM1 recruits LRRK2 to the cytoskeleton and controls its degradation, kinase activation, and cytotoxicity.

Stormo et al. use a quantitative mass spectrometry–based approach to identify the microtubule-associated E3 ubiquitin ligase TRIM1 as a novel interacting partne

03/09/2022

multi-factor modulated biogenesis of the mitochondrial multi-span protein Om14

Jialin Zhou, Doron Rapaport (Eberhard Karls Universität Tübingen) and colleagues provide new insights to the biogenesis of mitochondrial outer membrane proteins. They demonstrate that such proteins can follow various routes where both proteinaceous elements and membrane behavior regulate the efficiency and specificity of this process.

Zhou et al. provide new insights to the biogenesis of mitochondrial outer membrane proteins. They demonstrate that such proteins can follow various routes where

03/09/2022

In situ cryo-electron tomography reveals local cellular machineries for axon branch development | Journal of Cell Biology | Rockefeller University Press

Hana Nedozralova, Naoko Mizuno and colleagues (National Heart, Lung, and Blood Institute (NHLBI)) performed cryo-electron tomography on axon branches from mouse primary neurons and discovered concentrations of cellular activities at branching sites: ER spreading and ER comigration with microtubules, mitochondria fission, and protein synthesis in free and ER-attached polysomes.

Nedozralova et al. performed cryo-electron tomography on axon branches from mouse primary neurons and discovered concentrations of cellular activities at branch

03/08/2022

Sidekick dynamically rebalances contractile and protrusive forces to control tissue morphogenesis

Mechanical forces remodel epithelial structure during morphogenesis. However, the mechanisms by which cells sense, transduce and respond to mechanical forces are not well understood. Malin et. al. (Tufts University School of Medicine) identified a mechanotransduction pathway involving the adhesion protein Sidekick, the WAVE regulatory complex (WRC) and Polychaetoid (Pyd)/Zonula adherens-1 (ZO-1). The WRC is recruited by Sdk to tricellular junctions in contracted contacts to expand the contacts and reduce tension. In expanded contacts under reduced tension, Pyd/ZO-1 is recruited by Sdk to tricellular junctions to transmit tensile force to contract the contacts. These results place Sdk and its partners at the center of a mechanosensitive pathway operating at tricellular junctions to rebalance contractile and protrusive forces during epithelial remodeling.

Malin et al. show that the homophilic adhesion molecule Sidekick interacts alternately with the WAVE regulatory complex and with Polychaetoid/Zonula occludence-

03/08/2022

Happy International Women's Day

Today on #InternationalWomensDay we celebrate women scientists #WomenInSTEM who continue to #BreakTheBias! Happy #IWD2022 #WHM2022
https://www.internationalwomensday.com

03/07/2022

Mechanosensitive calcium flashes promote sustained RhoA activation during tight junction remodeling

Saranyaraajan Varadarajan, Ann L. Miller and colleagues (University of Michigan) find that calcium flashes regulate epithelial barrier function. Using live imaging, optogenetics, and laser-induced tight junction injury, they show that mechanosensitive channel-dependent calcium flashes promote sustained local activation of RhoA, allowing cells to repair tight junction leaks induced by mechanical stimuli.

Varadarajan et al. find that calcium flashes regulate epithelial barrier function. Using live imaging, optogenetics, and laser-induced tight junction injury, th

03/07/2022

On the cover of our March Issue: Confocal projection of a fixed Drosophila embryo expressing endogenously YFP-tagged Rab7 as marker for late endosomes (yellow), and stained for actin (phalloidin-ATTO647, white), the tracheal lumen (Chitin-binding protein-Alexa546, magenta), and nuclei (DAPI, blue). Late endosomes organize actin at the growing tip of tracheal terminal cells to regulate their morphogenesis. From Ríos-Barrera and Leptin (https://bit.ly/3FLbSxH).
Read JCB’s March Issue: https://bit.ly/3swCgYF

03/03/2022

Fyn and TOM1L1 are recruited to clathrin-coated pits and regulate Akt signaling

Ligand binding to EGF receptor (EGFR) triggers signaling and concomitant receptor recruitment to clathrin-coated pits. This study from Rebecca Cabral-Dias, Stefanie Lucarelli, Costin N. Antonescu and colleagues (Ryerson University) reveals that the signaling adaptor TOM1L1 recruits Fyn to a specialized subset of clathrin-coated pits and is required for SHIP2 recruitment and regulation of Akt signaling by EGFR.

Ligand binding to EGF receptor (EGFR) triggers signaling and concomitant receptor recruitment to clathrin-coated pits. This study reveals that the signaling ada

03/03/2022

Cdc14 spatiotemporally dephosphorylates Atg13 to activate autophagy during meiotic divisions

Wenzhi Feng, Fei Wang and colleagues (UT Southwestern Medical Center) report a meiosis-tailored role of Cdc14 that governs autophagy. By dephosphorylating Atg13, Cdc14 stimulates Atg1 kinase activity and thus autophagy at anaphase I and anaphase II to facilitate meiosis progression, meiosis exit, and sporulation.

Feng et al. report a meiosis-tailored mechanism of Cdc14 that governs autophagy. By dephosphorylating Atg13, Cdc14 stimulates Atg1 kinase activity and thus auto

02/24/2022

Bo Zhong: Captive by the viral immune escape | Journal of Cell Biology | Rockefeller University Press

Bo Zhong (Wuhan University) studies the regulation of antiviral innate immunity, inflammation, and tumorigenesis by the protein ubiquitination system. For our latest People & Ideas, we contacted Bo to learn more about his current and future scientific endeavors.

Bo Zhong studies the regulation of the antiviral innate immunity, inflammation, and tumorigenesis by the protein ubiquitination system.

02/24/2022

Ribbon boosts ribosomal protein gene expression to coordinate organ form and function

Rajprasad Loganathan, Deborah J. Andrew and colleagues (Johns Hopkins Medicine) report a role for the transcriptional regulation of embryonic cell growth during Drosophila tubulogenesis. Ribbon, a BTB/POZ nuclear protein, mediates salivary gland cell growth by boosting transcription of the entire ribosomal protein gene repertoire and mediates tracheal cell growth through other targets.

Loganathan et al. report a role for the transcriptional regulation of embryonic cell growth during Drosophila tubulogenesis. Ribbon, a BTB/POZ nuclear protein,