JCB

New issue: January 9th

In today's new issue of JCB, Hayakawa et al. reveal that half of all the proteins that form the budding yeast nuclear pore complex are either mono- or poly-ubiquitinated. And they describe in detail how the ubiquitination of one pore component, Nup159, helps recruit dynein to the nuclear envelope in order to orient the spindle and move the nucleus to the bud neck during mitosis. More details here.

Ardite et al. describe how increased production of a microRNA leads to progressive muscle deterioration in Duchenne muscular dystrophy patients. As patients age, their damaged muscle cells are gradually replaced by collagen-rich fibrous tissue. Ardite et al. show that the cytokine TGFbeta induces this muscle fibrosis in part by stimulating production of the microRNA, miR-21, which increases fibroblast proliferation and boosts collagen production. You can read more in this summary.

Tang and Brieher reconstitute the assembly of actin filaments at intercellular junctions in vitro, and use their assay to identify key roles for the Arp2/3 actin nucleation complex and the actin-bundling protein alpha-actinin-4 in the process. These two proteins help assemble actin filaments at the junctions themselves, rather than capturing filaments formed nearby in the cytosol. Moreover, as described in this week's In Focus, the researchers find that versions of alpha-actinin-4 containing a mutation associated with human kidney disease inhibit actin assembly at adherens junctions in vitro and in vivo.

Wynne et al. image the movements of homologous chromosomes in living nematodes in order to describe how they pair up at the beginning of meiosis. These movements rely on chromosome sequences called pairing centers that coupled by a network of proteins across the nuclear envelope to dynein motors and microtubules in the cytoplasm. Dynein is shown to drive rapid, directional movements of the chromosomes to help them pair up with their homologues, but the chromosomes also show slower, dynein-independent motions that help them to pair up even in the absence of the motor protein. More here.

And Arsic et al. reveal a surprising new function for Cyclin A2, a protein best known for regulating cyclin-dependent kinases (CDKs) to control progression through the cell cycle. The researchers show that Cyclin A2 also has a CDK-independent function in inhibiting cell migration by potentiating a guanine nucleotide exchange factor that activates the RhoA GTPase. You can find out more in this month's biobytes podcast, where you can also learn about Giagtzoglou et al.'s paper describing a protein called dEHBP1, which regulates Notch signaling by promoting the exocytosis and recycling of the transmembrane ligand Delta.

There's lots of other interesting papers in today's new issue - you can find them all on our table of contents by clicking here.

Cover image courtesy of David Wynne and Ofer Rog.

New issue: December 26th

In today’s new issue of JCB, Hégarat et al. describe how the Aurora family of protein kinases regulates chromosome and microtubule dynamics in mitosis. Cells lacking either Aurora A or Aurora B fail to properly align their chromosomes on the mitotic spindle, resulting in chromosome mis-segregations. As described in this summary, cells lacking Aurora A AND Aurora B, on the other hand, fail to depolymerize spindle microtubules in anaphase, preventing sister chromatid separation.

Schmidt et al. describe a signaling pathway that helps embed acetylcholine receptors in the post-synaptic membrane of neuromuscular junctions. Neuregulin signaling molecules bind to their ErbB receptors and induce the phosphorylation of a post-synaptic scaffold protein called alpha-dystrobrevin1, which stabilizes acetylcholine receptors at the post-synapse to maintain proper synaptic neurotranmission. As explained in this week’s In Focus, the signaling pathway seems to particularly affect acetylcholine receptors that have undergone a round of endocytic recycling, though why this population of receptors behaves differently isn’t clear. Meanwhile, Baez et al. describe how cytoplasmic RNA granules regulate post-synaptic remodeling. The researchers identify S-foci, which contain the translational repressor Smaug1 and which regulate the local translation of mRNAs encoding proteins (e.g. CaMKinaseII) in response to NMDA receptor stimulation.

Emond et al. reveal a new way for cells to adhere to each other. Though classical cadherins like E- and N-cadherin are known to mediate intercellular adhesion, the role of the related protocadherin proteins in holding cells together is much less clear. Emond et al. find that Protocadherin-19 becomes adhesive when it forms a complex with N-cadherin, so that it forms homophilic adhesions between neighboring cells. N-cadherin switches on Protocadherin-19’s adhesive properties, but it doesn’t mediate the intercellular adhesion itself. More here.

Sideridou et al. report that Cdc6, a protein that permits cells to replicate their DNA, also induces epithelial to mesenchymal transitions by shutting down the expression of E-cadherin. Cdc6 overexpression may therefore aid the progression of cancer by stimulating both DNA synthesis and metastasis. You can find a longer summary here.

And Nekrasova et al. reveal that the two types of cadherin molecules that assemble into desmosomal adhesions are transported to the plasma membrane by two distinct kinesin motors. You can learn more in this month’s biosights, in which senior author Kathleen Green explains why using two independent transport mechanisms to build desmosomes might allow cells to tailor the strength of their adhesions during development and disease.

That’s all we have time for today, but you can find lots of other interesting papers in today’s new issue by visiting the table of contents here.

Cover image courtesy of Nadia Hégarat and Helfrid Hochegger.

New issue: December 12th

In today’s new issue of JCB, Gong et al. describe how a protein called Fsp27 promotes the growth of lipid droplets in fat-storing adipocytes. Fsp27 localizes to the site where neighboring droplets contact each other, and facilitates the transfer of lipids from the smaller to the larger droplet. More in this summary. Meanwhile, de Saint-Jean et al. describe how a protein called Osh4p exchanges sterols and phosphatidylinositol-4-phosphate between organelles in order to set up a sterol gradient across the different organelles of the secretory pathway. Tim Levine provides a comment on this surprising finding.

Bruns et al. identify a novel membrane-bound compartment in yeast called CUPS. This “Compartment for Unconventional Protein Secretion” contains many of the proteins required to deliver the Acyl-CoA-binding protein Acb1 to the surface of starving budding yeast via a recently-discovered pathway that sidesteps the usual secretory route through the ER and Golgi apparatus. You can learn more about the proteins that localize to CUPS, and how the organelle compares to similar compartments in the autophagy pathway, in this summary article.

And Garcia et al. reveal that the shape of septin filaments can be modulated by the incorporation of different septin subunits and by septin phosphorylation. Septins are a conserved family of GTPases that hetero-oligomerize into filamentous structures in order to control a variety of cellular processes, including budding yeast cytokinesis, where septins form an organized collar around the bud neck. Complexes containing the septin Cdc11 assemble into long, straight rods, but Garcia et al. find that substituting another septin, Shs1, in place of Cdc11 drives the formation of ring-shaped structures. Moreover, the phosphorylation of Shs1 can promote the assembly of septins into a gauze-like meshwork. Read more about how this all relates to septins’ functions at the yeast bud neck in this week’s In Focus.

Yamaguchi et al. perform some beautiful in vivo imaging to investigate how apoptosis contributes to neural tube closure in mouse embryonic brains (summary here) and Janes et al. examine the crosstalk between different subclasses of the Eph receptor tyrosine kinase family. This latter paper is covered in more detail in this month’s biobytes podcast, in which you can also hear Vania Braga describe her lab’s recent paper explaining how the cell junction protein Ajuba regulates the Rac GTPase at intercellular contacts. You can listen below or subscribe in iTunes.

That’s all for today, but don’t forget to check out all the other great papers published in today’s new issue. You can find them all on our table of contents.

Cover image courtesy of Zhiqi Sun.

ASCB 2011: The ubiquity of ubiquitin

Co-chairs Claudio Joazeiro (The Scripps Research Institute) and Frauke Melchior (University of Heidelberg) put together a minisymposium on the third day of ASCB 2011 that nicely highlighted the diversity of cellular functions performed by ubiquitin and ubiquitin-like proteins.

Ubiquitin is best known for its role in protein degradation when E3 ubiquitin ligases tag proteins with ubiquitin in order to target them to the proteasome. But, as Joazeiro described in his opening talk, individual E3 ligases can take part in very specific degradation pathways, a fact exemplified by Listerin, an E3 ligase whose mutation in mice causes motor neuron degeneration. Joazeiro showed that the yeast homolog of Listerin, Ltn1, is involved in a type of protein degradation linked to an mRNA quality control pathway called non-stop mRNA decay. This pathway rids cells of mRNAs that lack a proper stop codon, but an abnormal polypeptide is always produced before the mRNA can be eliminated. Joazeiro showed that Ltn1 associates with ribosomes and targets for destruction the proteins produced from non-stop mRNAs.

Probably the second-best known role for ubiquitination is in cell signaling. Fumiyo Ikeda (IMBA, Vienna) presented data from her recent paper describing how SHARPIN - a component of the Linear Ubiquitin Chain Assembly Complex (LUBAC) - regulates two signaling pathways. SHARPIN promotes NFkappaB signaling by mediating the ubiquitination of and NFkappaB regulator called NEMO, and it also inhibits cell death by restricting apoptotic signaling through the death domain-containing protein FADD. SHARPIN-deficient mice therefore suffer from increased apoptosis and inflammation.

The following two talks dealt with some less-appreciated roles of ubiquitination. Corinne Albiges-Rizo (Institut Albert Bonniot, Grenoble) discussed how ubiquitination of an integrin-binding protein helps regulate cell adhesion and migration. And Yanzhuang Wang (University of Michigan) described how the E3 ubiquitin ligase HACE1 is required for the reassembly of the Golgi apparatus after mitosis. (Interestingly, HACE1 is a tumor suppressor. Is there a connection between a failure to reassemble the Golgi and tumorigenesis?)

The final two talks examined the cellular functions of ubiquitin-like molecules. Jay Debnath (UC San Francisco) spoke about Atg12, a ubiquitin-like modifier required for expanding autophagosomal membranes during macroautophagy. Debnath and colleagues found that Atg12 can be conjugated to Atg3, a protein involved in the conjugation of another ubiquitin-like protein, LC3, that is also required for autophagy. The Atg12-Atg3 conjugate isn't required for starvation-induced autophagy, however. Instead, preventing the formation of Atg12-Atg3 conjugates blocks the related pathway of mitophagy (in which mitochondria are degraded) and also inhibits mitochondrial fusion, resulting in cells with increased numbers of highly-fragmented mitochondria. Debnath thinks that Atg12 may be conjugated to several other proteins and have important functions in a number of other cellular pathways as well.

And session co-chair Frauke Melchior finished off the session with a presentation on how oxidative stress regulates the small, ubiquitin-like modifier SUMO. Sumoylation is a reversible post-translational modification that affects the function of many different proteins. Reactive oxygen species cause a reduction in the sumoylation of many target proteins. In 2006, Melchior published that ROS inhibit sumoylation by promoting the formation of a disulphide bond between catalytic cysteine residues in two enzymes required for sumoylation, blocking the activity of both proteins. Melchior now described some follow up experiments to this initial report, looking at the potential functional consequences to cells if oxidative stress fails to shut down sumoylation.

 

 

ASCB 2011: Simulating the spindle

Today at ASCB, Francois Nedelec (EMBL) gave a great talk in the "Self-Organization of Cellular Structures" symposium about using the Cytosim program to model cytoskeletal dynamics. His presentation drew heavily on his JCB paper modeling the Xenopus meiotic spindle, which you can learn about in this biosights video we made to accompany the study...

 

ASCB 2011: A cascade of Rabs and Arfs

On the opening day of the annual ASCB meeting in Denver, CO, I decided to check out the 'Special interest subgroup' on Rabs and Arfs - two families of small GTPases that regulate a variety of membrane trafficking events in eukaryotic cells.

The session - organized by Elizabeth Sztul (University of Alabama) and Angela Wandinger-Ness (University of New Mexico) - covered a variety of the different functions performed by these GTPases and the many proteins that regulate them. Cathy Jackson (CNRS, France) discussed how a guanine nucleotide exchange factor (GEF) that activates the Arf1 GTPase helps deliver key proteins to fat-storing lipid droplets, while James Goldenring (Vanderbilt University) described how the regulation of endocytic recycling pathways in polarized epithelial cells by Rab25 helps to suppress colon cancer. Wandinger-Ness explained how mutations in Rab7 cause Charcot-Marie-Tooth disease Type 2B, and discussed how Rabs might be targeted therapeutically by small molecules.

Nava Segev (University of Illinois) discussed the regulation of Rab proteins (known as Ypts in budding yeast). In addition to GEFs and other factors that regulate Rab localization and activation into the GTP-bound state, Segev explained that the choice of effector protein that interacts with the active GTPase is also a critical control point that allows Rabs to function in multiple different pathways. For example, the yeast Rabs Ypt31 and Ypt32 function in both Golgi-to-plasma membrane and endosome-to-Golgi trafficking, using different effectors for each of the two pathways. 

Roger Goody (MPI of Molecular Physiology, Germany) stressed the importance of GEFs in determining when and where Rabs are activated, and described how normal Rab function can be subverted by pathogens such as Legionella. Once Legionella have been internalized into a vacuole within a host cell, they secrete a number of factors that induce the recruitment of ER-derived vesicles that eventually convert the Legionella-containing vacuole into something that resembles the ER. One of these secreted factors is a protein called DrrA, which acts as a GEF that activates and recruits the host's Rab1 molecules in order to promote ER-vesicle transport to the Legionella-containing vacuole. Moreover, DrrA catalyzes the addition of an AMP-molecule onto Rab1, blocking its association with host cell regulatory and effector proteins. But AMPylated Rab1 can still interact with Legionella LidA (a 'super effector' that interacts with multiple host cell Rabs), suggesting that DrrA and LidA work together to recruit early secretory vesicles to Legionella-containing vacuoles. For a broader view of how pathogens subvert host cell membrane trafficking pathways, read this recent review from JCB. Meanwhile, Rick Kahn (Emory University) discussed the potential contribution of vesicular cargo to determining exactly where and when GEFs are prompted to activate GTPases to stimulate vesicle transport.

One recurring theme in the session was that of GTPase cascades, in which a series of Arfs and Rabs either promote or inhibit each other's activation. Arnaud Echard (Institut Pasteur, France) revealed how two GTPases that antagonize each other to ensure that cells complete cytokinesis; co-chair Elizabeth Sztul explained how one GTPase activates another to recruit different vesicle coats to the Golgi; and Sean Munro (MRC-LMB, UK) described a chain of three GTPases that act consecutively to recruit proteins to Golgi membranes.

All in all, there was plenty to ponder on from this session. With Arfs and Rabs regulating so many critical transport processes in cells, it's no wonder that their regulation is so complex. It seems that many questions remain about how cells decide exactly when and where to switch these GTPases on.

New issue: November 28th

In today's new issue of JCB, Wen et al. reveal that the development of Alzheimer's disease might be promoted by defective recycling of the enzyme beta-secretase. Vps35 is a component of the retromer complex that transports proteins from endosomes to the Golgi. In the absence of Vps35, cells accumulate extra beta-secretase in their endosomes, where the enzyme may be more active in converting amyloid precursor protein into toxic Abeta peptides. Mice prone to Alzheimer's disease develop neurodegenerative symptoms even quicker if they lack one copy of the VPS35 gene. You can read more in this summary.

Calvert et al. find that large cells divide at a faster rate than small cells in the filamentous fungus Neurospora crassa. The reason seems to be that larger cells start off with a higher amount of myosin II in the contractile ring that separates cells during cytokinesis, which allows the rings to constrict more rapidly. More here.

Karotki et al. demonstrate that the components of eisosomes - protein complexes that spatially organize the plasma membrane - carry out their function by assembling into a lipid-binding filamentous scaffold. As explained in this week's In Focus, Karotki et al. show that, in vitro, eisosome proteins assemble into helical filaments that can re-shape artificial liposomes, suggesting that the proteins may act similarly to remodel the plasma membrane. Indeed, this issue's cover image shows a helical eisosome filament on the cytoplasmic face of the budding yeast plasma membrane.

Lasserre et al. describe how the kinase HPK1 phosphorylates two signaling adaptor proteins in order to disassembly T cell receptor microclusters and switch off T cell signaling. (Summary here). And, sticking with T cells, Zyss et al. reveal that casein kinase I delta helps to reposition the centrosome toward the immunological synapse (where T-lymphocytes contact their target, antigen-presenting cells), perhaps by working with the microtubule plus-end binding protein EB1 to regulate microtubule growth. You can find out more in this month's biosights, in which senior author Fanni Gergely explains CK1 delta's role in centrosome translocation in more detail...

Lots more interesting papers that I didn't have time to mention here. You can find them all on our table of contents by clicking this link.

 

 

 

New issue: November 14th

Here’s a few quick highlights from the new issue of JCB…

Krementsova et al. describe how the budding yeast myosin Myo4 gains the ability to walk along actin fibers only when coupled to its mRNA cargo. Unlike many other myosin motors, Myo4 is normally monomeric, and is therefore unable to take processive steps along actin by itself. But Krementsova et al. show that the mRNA-binding protein She2 recruits two Myo4 molecules, allowing the complex to walk “hand-over-hand” along actin cables, just like regular myosin dimers. You can read more in this summary.

Morin-Leisk et al. investigate the function of atlastin, a GTPase that drives the tethering and fusion of ER membrane tubules, thereby helping the ER network to maintain a branched morphology. Morin-Leisk et al. identify an intramolecular salt bridge essential for a conformational change in atlastin that is thought to promote membrane fusion. Moreover, the researchers provide evidence that this conformational change isn’t driven by GTP hydrolysis, which, says senior author Tina Lee, raises the question of which step in membrane fusion is dependent on atlastin’s catalytic activity.

Pigino et al. use cryoelectron tomography to reveal the three-dimensional structure of radial spokes, key regulatory complexes that determine how cilia and flagella move. (You can see these structures – colored red – on the journal’s cover). By comparing various mutant strains of Chlamydomonas, the researchers were able to assign many of the 23 proteins that form the spokes to specific locations within these structures and, as explained in this summary, Pigino et al.’s results support the idea that the radial spokes assemble through the dimerization of smaller, precursor structures.

Meanwhile, two papers reveal that there’s much more of the centromeric protein CENP-A at budding yeast centromeres than previously thought. CENP-A is a histone H3 variant that marks centromeric chromatin, and it had been assumed that there were only two copies of the protein at every centromere in budding yeast. But Coffman et al. and Lawrimore et al. now show that there’s between 5 and 8 copies of CENP-A per centromere. Because CENP-A has previously been used as a standard to count the relative numbers of kinetochore proteins, the new estimate means that kinetochore proteins are 3-4 times more abundant than previously estimated, which, as Ted Salmon explains in this week’s In Focus, helps explain how these complexes attach to spindle microtubules during mitosis.

And finally for today, Specht et al. describe how the small heat shock protein Hsp42 helps to deposit misfolded proteins at specific locations within budding yeast cells. You can learn more in this month’s biobytes podcast, where you’ll also hear Charles Streuli explain his lab’s recent publication (Wang et al.), describing how integrin-based focal adhesions control cell proliferation.

There are lots of other great papers to discover in our new issue.You can find them all on our table of contents by clicking here. 

Cover image courtesy of Pigino et al.

New issue: October 31st

In today’s new issue of JCB, Backs et al. reveal that Protein Kinase A may protect the heart from stress by inducing the proteolytic cleavage of the histone deacetylase HDAC4. Prolonged stress can inhibit HDAC4, leading to the expression of genes that induce harmful remodeling of cardiac muscle. But the PKA-induced cleavage of HDAC4 generates an N-terminal fragment of the histone deacetylase that is insensitive to stress signaling, and which can therefore continue to repress harmful cardiac-remodeling genes. More here.

Yoon et al. describe how two signaling pathways combine to ensure that cells only grow when sufficient nutrients are available. In the presence of amino acids, the growth-promoting kinase complex mTORC1 is transported to lysosomes via a pathway involving the Rag family of small GTPases. Yoon et al. show that, at the same time, amino acids also cause the phosphoinositide kinase Vps34 to activate Phospholipase D1 and induce this enzyme’s translocation to lysosomes, where it can activate mTORC1 by generating phosphatidic acid. Cell growth is therefore permitted when amino acids stimulate the transport of both mTORC1 and Phospholipase D1 to lysosomes, though, as senior author Jie Chen tells me here, it's not clear why lysososomes are used as these enzyme's meeting point.

Demuro et al. use high-resolution imaging to reveal that oligomers of the Alzheimer’s disease-related peptide beta-amyloid can form calcium-permeable pores in the plasma membrane.  The resulting excess calcium influx can disrupt synaptic signaling and stimulate apoptosis. As explained in this week’s In Focus, Demuro et al.’s technique of optical patch-clamping measures the properties of many individual channels at the same time. This approach revealed that individual beta-amyloid pores have a wide variety of behaviors, possibly reflecting differences in the number of beta-amyloid peptides that assemble into each channel and, as cells were exposed to beta-amyloid oligomers for longer periods, the channels became more active, potentially corresponding to the progressive nature of Alzheimer’s disease. Intriguingly, the proteins associated with Huntington’s and Parkinson’s diseases may form similar calcium-permeable pores in the plasma membrane as well.

Meanwhile, Wee et al. reveal that the Ran GTPase orients the mitotic spindle by controlling the recruitment of the motor adaptor Mud to the cell cortex. Ran works with a protein called Canoe to recruit Mud, which, in turn, brings in the dynein/dynactin motor complex to help drag the spindle into position for oriented cell divisions that can determine daughter cell fate. A slightly longer summary is here.

And finally for today, Chen and Pollard describe how the actin-severing protein cofilin helps to assemble the actomyosin contractile ring in cytokinesis by limiting the actin-based connections between precursor structures called cytokinetic nodes. If cofilin is inactive, nodes maintain their connections for too long, causing them to clump together instead of spreading out evenly around the cell equator. As you can see in this month’s biosights, however, Chen and Pollard find that there’s an alpha-actinin-dependent backup mechanism that allows these clumped nodes to eventually form a contractile ring, even in the absence of cofilin-mediated severing.

As always, there are lots of other great papers in today’s new issue. You can find them all in our table of contents by clicking here.

Cover image courtesy of Brett Wee.

 

New issue: October 17th

Time for a quick look at some of the highlights from today’s new issue. 

Brownlee et al. describe how the phosphatase PP2A and its regulatory subunit Twins promote centriole duplication by activating the kinase Plk4. Plk4 initiates centriole duplication but, for most of the cell cycle, the kinase limits its own activity by phosphorylating itself, which triggers its degradation by the proteasome. Brownlee et al. show that, in mitosis, PP2A and Twins counteract Plk4 autophosphorylation, stabilizing the kinase and allowing it to initiate centriole duplication. Twins overexpression kept Plk4 active throughout the cell cycle, leading to centriole overamplication. Moreover, the SV40 small t-antigen, a viral oncogene, mimicked Twins’ ability to overactivate Plk4 and induce centriole amplification, which may be a key step in tumorigenesis as too many centrioles can lead to multipolar spindles and genomic instability. You can read more in this summary article.

Brill et al. investigate the organization and dynamics of Schwann cells at neuromuscular junctions, where they wrap around axon terminals to support neurotransmission. Although highly dynamic during development, Schwann cells settle down at mature neuromuscular junctions to occupy their own distinct, non-overlapping territories as seen in this weeks cover image where each of the individual Schwann cells are labeled with a different color. This tiled arrangement is maintained by spatial competition between the cells – when one Schwann cell is ablated, the others rapidly swoop in to fill its place. The Schwann cells are similarly activated if the axon itself fragments and disappears, only resuming their stable, segregated arrangement when the axon has re-grown. You can read more about these nerve terminal Schwann cells – and their potential function in synaptic remodeling – in this summary.

Snider et al. reveal that differential expression of two key metabolic enzymes may explain why some people are more susceptible to liver damage. By comparing mice with different sensitivies to a liver-damaging drug, the researchers find that increased sensitivity correlates with reduced expression of the “housekeeping” proteins GAPDH and NDPK. Knocking down these proteins in hepatocytes raised reactive oxygen species levels, whereas GAPDH overexpression offered dome protection against oxidative damage. GAPDH is aggregated in cirrhotic patient livers, suggesting that similar mechanisms may determine human sensitivities to liver injury. More here.

Hoppins et al. construct a high-density map of the genetic interactions between genes encoding mitochondrial and ER proteins, a systems-wide approach that allowed them to identify a scaffold-like protein complex called MitOS that helps to organize the mitochondrial inner membrane. It's a great example of our new "Tools" article format - if you missed it, here's our announcement from last month. Meanwhile, you can read how Hoppins et al. constructed their map, and why it allowed them to identify MitOS in this week’s In Focus.

Staying with mitochondria, Chen et al. reveal that the anti-apoptotic protein Bcl-Xl also promotes cell survival by regulating mitochondrial energetics. It does this by localizing to the mitochondrial inner membrane (a surprising location for a protein generally thought to be on the outer membrane), where it maintains mitochondrial membrane potential by keeping an unidentified proton channel closed to avoid wasteful proton leakage across the inner membrane. You can learn more in today’s biobytes podcast, where you can listen to senior author Marie Hardwick discuss her group’s work as well as hear Pura Muñoz-Cánoves explain her lab’s research (Perdiguero et al.) into how MAP kinase signaling regulates macrophages during muscle tissue repair.

Lots of other great papers in today’s new issue as well. You can find them all on our table of contents by clicking here. 

Cover image courtesy of Monika Brill.