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W.D.V.H. acknowledges support from National Institutes of Health (Grant: R01GM112077). S.B.O. acknowledges support from the Gordon and Betty Moore Foundations and National Science Foundation (Awards: 1715591 and 1901709). J.M.S.R. acknowledges support from Spanish Ministry of Economy and Competitiveness/FEDER Funds (Grants BIO2015-66426-R and RTI2018-097142-B-100) and the Human Frontier Science Program (Grant RGP0041/2017). V.A.R. acknowledges support from FEDER/Junta de Andalucia-Consejeria de Economia y Conocimiento (Grant E.FQM.113.UGR18). We would like to thank the beamline staff of ID30B of the ESRF (European Synchrotron Radiation Facility, Grenoble, France) for their assistance during data collection and the ESRF for the provision of time through proposals MX-2064., TEM-1 β-lactamase degrades β-lactam antibiotics with a strong preference for penicillins. Sequence reconstruction studies indicate that it evolved from ancestral enzymes that degraded a variety of β-lactam antibiotics with moderate efficiency. This generalist to specialist conversion involved more than 100 mutational changes, but conserved fold and catalytic residues, suggesting a role for dynamics in enzyme evolution. Here, we develop a conformational dynamics computational approach to rationally mold a protein flexibility profile on the basis of a hinge-shift mechanism. By deliberately weighting and altering the conformational dynamics of a putative Precambrian β-lactamase, we engineer enzyme specificity that mimics the modern TEM-1 β-lactamase with only 21 amino acid replacements. Our conformational dynamics design thus re-enacts the evolutionary process and provides a rational allosteric approach for manipulating function while conserving the enzyme active site., United States Department of Health & Human Services National Institutes of Health (NIH) - USA R01GM112077, Gordon and Betty Moore Foundations, National Science Foundation (NSF) 1715591 1901709, Spanish Ministry of Economy and Competitiveness/FEDER Funds BIO2015-66426-R RTI2018-097142-B-100, Human Frontier Science Program RGP0041/2017, FEDER/Junta de Andalucia-Consejeria de Economia y Conocimiento E.FQM.113.UGR18

Cells remodel their structure in response to mechanical strain. However, how mechanical forces are translated into biochemical signals that coordinate the structural changes observed at the plasma membrane (PM) and the underlying cytoskeleton during mechanoadaptation is unclear. Here, we show that PM mechanoadaptation is controlled by a tension-sensing pathway composed of c-Abl tyrosine kinase and membrane curvature regulator FBP17. FBP17 is recruited to caveolae to induce the formation of caveolar rosettes. FBP17 deficient cells have reduced rosette density, lack PM tension buffering capacity under osmotic shock, and cannot adapt to mechanical strain. Mechanistically, tension is transduced to the FBP17 F-BAR domain by direct phosphorylation mediated by c-Abl, a mechanosensitive molecule. This modification inhibits FBP17 membrane bending activity and releases FBP17-controlled inhibition of mDia1-dependent stress fibers, favoring membrane adaptation to increased tension. This mechanoprotective mechanism adapts the cell to changes in mechanical tension by coupling PM and actin cytoskeleton remodeling., Mechanical forces are sensed by cells and can alter plasma membrane properties, but biochemical changes underlying this are not clear. Here the authors show tension is sensed by c-Abl and FBP17, which couples changes in mechanical tension to remodelling of the plasma membrane and actin cytoskeleton.

It is unclear how the mitochondrial fusion protein Optic atrophy 1 (OPA1), which inhibits cristae remodeling, protects from mitochondrial dysfunction. Here we identify the mitochondrial F1Fo-ATP synthase as the effector of OPA1 in mitochondrial protection. In OPA1 overexpressing cells, the loss of proton electrochemical gradient caused by respiratory chain complex III inhibition is blunted and this protection is abolished by the ATP synthase inhibitor oligomycin. Mechanistically, OPA1 and ATP synthase can interact, but recombinant OPA1 fails to promote oligomerization of purified ATP synthase reconstituted in liposomes, suggesting that OPA1 favors ATP synthase oligomerization and reversal activity by modulating cristae shape. When ATP synthase oligomers are genetically destabilized by silencing the key dimerization subunit e, OPA1 is no longer able to preserve mitochondrial function and cell viability upon complex III inhibition. Thus, OPA1 protects mitochondria from respiratory chain inhibition by stabilizing cristae shape and favoring ATP synthase oligomerization., R.Q.-C. was supported by an AIRC Postdoctoral Fellowship, a Fondazione Umberto Veronesi Postdoctoral Fellowship and is currently a recipient of a Juan de la Cierva-Incorporación fellowship from the Spanish Ministry of Economy, Industry and Competitiveness (IJCI-2015–26225). This work was supported by Telethon-Italy GPP10005, GGP14187, GGP15091; AIRC Italy IG-15748, ERC FP7-282280, FP7 CIG PCIG13-GA-2013-618697; Italian Ministry of Research FIRB RBAP11Z3YA_005 to L.S. C.Ge. is supported by JST, CREST Grant JPMJCR13M4 (to Genij Kurisu and C.Ge.), the Platform for Drug Design, Discovery and Development from MEXT, Japan and the Grants-in-Aid for Scientific Research (Kiban B: 17H03647) from MEXT, Japan. JAE is supported by Spanish Ministry of Economy, Industry and Competitiveness (SAF2015-65633-R; SAF2015-71521-REDC). The CNIC is supported by MINECO and Pro-CNIC Foundation and is a SO-MINECO (award SEV-2015-0505).

In germinal centres (GC) mature B cells undergo intense proliferation and immunoglobulin gene modification before they differentiate into memory B cells or long-lived plasma cells (PC). GC B-cell-to-PC transition involves a major transcriptional switch that promotes a halt in cell proliferation and the production of secreted immunoglobulins. Here we show that the CCCTC-binding factor (CTCF) is required for the GC reaction in vivo, whereas in vitro the requirement for CTCF is not universal and instead depends on the pathways used for B-cell activation. CTCF maintains the GC transcriptional programme, allows a high proliferation rate, and represses the expression of Blimp-1, the master regulator of PC differentiation. Restoration of Blimp-1 levels partially rescues the proliferation defect of CTCF-deficient B cells. Thus, our data reveal an essential function of CTCF in maintaining the GC transcriptional programme and preventing premature PC differentiation., Activated B cells differentiate into antibody-producing plasma cells in the germinal centre in secondary lymphoid organs. Here the authors show that this differentiation process and related transcription programs are modulated by the transcription factor CTCF, partly by suppressing the premature expression of Blimp-1.

Appropriate therapeutic modulation of endothelial proliferation and sprouting is essential for the effective inhibition of angiogenesis in cancer or its induction in cardiovascular disease. The current view is that an increase in growth factor concentration, and the resulting mitogenic activity, increases both endothelial proliferation and sprouting. Here, we modulate mitogenic stimuli in different vascular contexts by interfering with the function of the VEGF and Notch signalling pathways at high spatiotemporal resolution in vivo. Contrary to the prevailing view, our results indicate that high mitogenic stimulation induced by VEGF, or Notch inhibition, arrests the proliferation of angiogenic vessels. This is due to the existence of a bell-shaped dose-response to VEGF and MAPK activity that is counteracted by Notch and p21, determining whether endothelial cells sprout, proliferate, or become quiescent. The identified mechanism should be considered to achieve optimal therapeutic modulation of angiogenesis. Research in the R.B. group was supported by the European Research Council (ERC-2014-StG—638028), the Centro Nacional de Investigaciones Cardiovasculares (CNIC), and by the Ministerio de Economia, Industria y Competitividad (MEIC: SAF2013-44329-P, SAF2013-42359-ERC and RYC-2013-13209). The CNIC is supported by the Ministerio de Ciencia, Innovación y Universidades (MCNU) and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (SEV-2015–0505). S. Pontes-Quero and M. Fernandez-Chacon received PhD fellowships from the La Caixa bank. W. Luo received a COFUND CNIC International Postdoctoral fellowship. Sí

Methane is of great environmental importance as a greenhouse gas, and marine seeps are estimated to contribute some 37% of the geological sources; likewise mud volcanism provides another 11–17% (ref. 1). Methane hydrates are often found in the vicinity of submarine seeps and mud volcanoes2, and the project of commercializing this energy source is under way. Concomitantly, there is concern that anthropogenic climate change could destabilize hydrates, thereby potentially releasing large quantities of methane into the ocean and atmosphere3,4,5. Thus there are both environmental and economic reasons to be interested in methane associated with seeps and mud volcanism. A mud volcano is a geological structure on land or in the oceans in which water plus fine particulates—‘mud’—issues from a conduit typically topped by a conical hill with a crater. The emerging mud is generally accompanied by methane, both dissolved and, if the concentration exceeds the saturation concentration, as bubbles6. A submarine seep, on the other hand, has similar fluid flow through the porous sediment constituting the seabed without the conical structure or open conduit. What physical forces drive such fluid flows? We find that both buoyancy and osmotic effects are present in cold seeps and mud volcanism in which, rather than being a passive element, methane is its driving force. Some researchers have suggested the importance of considering osmosis in seeps and mud volcanism7,8. Clays and shales are known to possess the semipermeability necessary for osmosis, associated with charge and pore-size effects9,10. Moreover, methane hydrates frequently exist in the sediments around a cold seep or mud volcano2,6. As hydrate forms, the sediment plus hydrate becomes progressively less permeable11,12. However, other mechanisms involving adsorption and chemical reaction can also produce significant osmotic pressures13,14,15,16,17,18,19,20. Methane is shown to adsorb onto sediments21,22,23,24. Hydrates form in pores under a wider range of conditions than in the bulk25 and methane molecules adsorb onto the cages of methane hydrate during the hydrate growth process26,27. Thus, we propose below that given a supply of methane, a submarine cold seep or mud volcano can function as a geological instance of an osmotic pump9,28,29. We find cause for concern that this convective pump mechanism facilitates methane hydrate destabilization under anthropogenic climate change., The financial support of the UK Leverhulme Trust project RPG-2015-002. J.H.E.C. acknowledges the financial support of the Spanish MINCINN project FIS2013-48444-C2-2

The ideal magnetocaloric material would lay at the borderline of a first-order and a second-order phase transition. Hence, it is crucial to unambiguously determine the order of phase transitions for both applied magnetocaloric research as well as the characterization of other phase change materials. Although Ehrenfest provided a conceptually simple definition of the order of a phase transition, the known techniques for its determination based on magnetic measurements either provide erroneous results for specific cases or require extensive data analysis that depends on subjective appreciations of qualitative features of the data. Here we report a quantitative fingerprint of first-order thermomagnetic phase transitions: the exponent n from field dependence of magnetic entropy change presents a maximum of n > 2 only for first-order thermomagnetic phase transitions. This model-independent parameter allows evaluating the order of phase transition without any subjective interpretations, as we show for different types of materials and for the Bean–Rodbell model., Magnetocaloric materials often perform best when their magnetic transitions are at the boundary between first- and second-order behavior. Here the authors propose a simple criterion to determine the order of a transition, which may accelerate future magnetocaloric material searches.

The viability of building artificial metabolic pathways within a cell will depend on our ability to design biocompatible and orthogonal catalysts capable of achieving non-natural transformations. In this context, transition metal complexes offer unique possibilities to develop catalytic reactions that do not occur in nature. However, translating the potential of metal catalysts to living cells poses numerous challenges associated to their biocompatibility, and their stability and reactivity in crowded aqueous environments. Here we report a gold-mediated C-C bond formation that occurs in complex aqueous habitats, and demonstrate that the reaction can be translated to living mammalian cells. Key to the success of the process is the use of designed, water-activatable gold chloride complexes. Moreover, we demonstrate the viability of achieving the gold-promoted process in parallel with a ruthenium-mediated reaction, inside living cells, and in a bioorthogonal and mutually orthogonal manner., This work has received financial support from Spanish grants (SAF2013-41943-R, SAF2016-76689-R, Orfeo-cinqa network CTQ2016-81797-REDC), the Xunta de Galicia (2015-CP082, ED431C 2017/19, and Centro Singular de Investigación de Galicia accreditation 2016-2019, ED431G/09), the European Union (European Regional Development Fund-ERDF), and the European Research Council (Advanced Grant No. 340055). M.T.G. thanks the Ministerio de Economía y Competitividad for the Juan de la Cierva-Incorporación fellowship (IJCI-2015-23210). The authors thank R. Menaya- Vargas for excellent technical assistance and M. Marcos for helpful contributions on MS analysis.

During development, mesodermal progenitors from the first heart field (FHF) form a primitive cardiac tube, to which progenitors from the second heart field (SHF) are added. The contribution of FHF and SHF progenitors to the adult zebrafish heart has not been studied to date. Here we find, using genetic tbx5a lineage tracing tools, that the ventricular myocardium in the adult zebrafish is mainly derived from tbx5a+ cells, with a small contribution from tbx5a− SHF progenitors. Notably, ablation of ventricular tbx5a+-derived cardiomyocytes in the embryo is compensated by expansion of SHF-derived cells. In the adult, tbx5a expression is restricted to the trabeculae and excluded from the outer cortical layer. tbx5a-lineage tracing revealed that trabecular cardiomyocytes can switch their fate and differentiate into cortical myocardium during adult heart regeneration. We conclude that a high degree of cardiomyocyte cell fate plasticity contributes to efficient regeneration., Funding was through FPU12/03007 and BFU2014–56970–P (Plan Estatal de Investigación Científica y Técnica y de Innovación 2013–2016, Programa Estatal de I+D+i Orientada a los Retos de la Sociedad Retos Investigación: Proyectos I+D+i 2016, del Ministerio de Economía competitividad e Industria), and co-funding by Fondo Europeo de Desarrollo Regional (FEDER) (H.S. and N.M.); Swiss National Science Foundation grant 31003A_159721, ANR-SNF collaborative Project 320030E-164245, and the ERC starting grant 337703–zebra–Heart (N.M.). A.E. is enrolled into PhD specialization Cutting Edge Microscopy offered by the Graduate School for Cellular and Biomedical Sciences (GCB) and the Microscopy Imaging Center (MIC). The CNIC is supported by the Ministry of Economy, Industry and Competitiveness (MEIC) and the Pro CNIC Foundation, and is a Severo Ochoa Center of Excellence (MEIC award SEV-2015-0505). Further support was from the Canton of Zürich, project grant from the Swiss Heart Foundation (A.F. and C. Mosimann); the Swiss National Science Foundation (SNSF) professorship (PP00P3_139093) and a Marie Curie Career Integration Grant from the European Commission (CIG PCIG14-GA-2013-631984) (C. Mosimann).

Increasing the thermogenic capacity of adipose tissue to enhance organismal energy expenditure is considered a promising therapeutic strategy to combat obesity. Here, we report that expression of the p38 MAPK activator MKK6 is elevated in white adipose tissue of obese individuals. Using knockout animals and shRNA, we show that Mkk6 deletion increases energy expenditure and thermogenic capacity of white adipose tissue, protecting mice against diet-induced obesity and the development of diabetes. Deletion of Mkk6 increases T3-stimulated UC P1 expression in adipocytes, thereby increasing their thermogenic capacity. Mechanistically, we demonstrate that, in white adipose tissue, p38 is activated by an alternative pathway involving AMPK, TAK, and TAB. Our results identify MKK6 in adipocytes as a potential therapeutic target to reduce obesity., Brown and beige adipose tissues dissipate heat via uncoupling protein 1 (UCP1). Here the authors show that the stress activated kinase MKK6 acts as a repressor of UCP1 expression, suggesting that its inhibition promotes adipose tissue browning and increases organismal energy expenditure.

The beta 1-adrenergic-receptor (ADRB1) antagonist metoprolol reduces infarct size in acute myocardial infarction (AMI) patients. The prevailing view has been that metoprolol acts mainly on cardiomyocytes. Here, we demonstrate that metoprolol reduces reperfusion injury by targeting the haematopoietic compartment. Metoprolol inhibits neutrophil migration in an ADRB1-dependent manner. Metoprolol acts during early phases of neutrophil recruitment by impairing structural and functional rearrangements needed for productive engagement of circulating platelets, resulting in erratic intravascular dynamics and blunted inflammation. Depletion of neutrophils, ablation of Adrb1 in haematopoietic cells, or blockade of PSGL-1, the receptor involved in neutrophil-platelet interactions, fully abrogated metoprolol's infarct-limiting effects. The association between neutrophil count and microvascular obstruction is abolished in metoprolol-treated AMI patients. Metoprolol inhibits neutrophil-platelet interactions in AMI patients by targeting neutrophils. Identification of the relevant role of ADRB1 in haematopoietic cells during acute injury and the protective role upon its modulation offers potential for developing new therapeutic strategies. We are grateful to all the METOCARD-CNIC trial investigators and to Noemi Escalera for coordinating the clinical work and Maite D. Rodriguez for handling human samples (CNIC). Angel Macias and Barulio-Perez-Asenjo (CNIC) performed the MRI studies. Noelia A-Gonzalez (CNIC) supplied the LysM-GFP + mice. R.P. Khaton, J. Mateos and V. Zorita provided technical support and animal care. M. Casanova-Acebes gave advice on neutrophil isolation. J.M. Adrover for IVM technical advice. R. Doohan, A. Guijarro and A. Molina-Iracheta provided technical support in histology. A. M. Santos-Beneit helped with microscopy image analysis and movie editing. We also thank the CNIC Animal, Cellomics and Microscopy units for support. Simon Bartlett provided English editing. We are grateful to Eeva I. Soininen and Ana I. Castillo for their inconditional support and management of the grants supporting this work. This work was supported by a competitive grant from the Institute of Health Carlos III and the European Regional Development Fund (ERDF/FEDER) (PI10/02268, PI13/01979 \& RD12/0042/0054). R.F.-J. was the recipient of non-overlapping grants from the Institute of Health Carlos III and ERDF/FEDER (Rio Hortega fellowship) and the Fundacion Jesus Serra, the Fundacion Interhospitalaria de Investigacion Cardiovascular (FIC) and the CNIC (FICNIC fellowship). A.H. is funded by MINECO and ERDF/FEDER (SAF2015-65607-R) and Fundacio La Marato-TV3 (120/C/2015-20153032). The CNIC is supported by the Spanish Ministry of Economy and Competitiveness (MINECO) and the Pro-CNIC Foundation, and is a Severo Ochoa Center of Excellence (MINECO award SEV-2015-0505). Borja Ibanez is the 2010 Princess of Girona awardee in Science. Sí

Photolithography has been a major enabling tool for miniaturisation of silicon devices that underpinned the electronics revolution. Rapid, high-resolution patterning of key material characteristics would, similarly, accelerate the advent of molecular electronics and photonics. Here we advance a versatile approach employing local diffusion of functional small-molecular compounds through a solution-processed ‘molecular gate’ interlayer. Diffusion is activated using laser light or solvent vapour jets―a process that can be finely modulated down to molecule-on-demand deposition precision with almost photolithographic resolution (3 S cm–1 for improved electronic devices. Finally, we demonstrate the unique capability for one-step patterning of multiple functionalities by spatially modulating composition in ternary blends, leading to locally tunable photoluminescence from blue to red., We are indebted to Enrique Pascual (ICMAB-CSIC) for providing insights into laser patterning and Lou Kiss (Middlesex University) for freely shared advice on the preparation of the graphics. We express our deepest gratitude to Paul Smith (ETH Zürich) for critically reviewing the manuscript. We thank Miquel Casademont-Viñas (ICMAB-CSIC) for invaluable contribution to exploring the limits of the method, and Agustín Mihi and Andrés Gómez (ICMAB-CSIC) for assistance with optical spectroscopy and AFM analysis. We also thank Daniel Kremer and Hans-Werner Schmidt (Universität Bayreuth) for their customary hospitality and assistance with DSC measurements. We further acknowledge financial support from the Spanish Ministry of Economy, Industry and Competitiveness through the “Severo Ochoa” Programme for Centers of Excellence in R&D (SEV-2015-0496) and project reference PGC2018-095411-B-I00, as well as the European Research Council (ERC) under grant agreement number 648901.