Browsing by Subject "SITES"

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  • Fernandez-Llamazares, Alvaro; Lopez-Baucells, Adria; Rocha, Ricardo; Andriamitandrina, Santatra F. M.; Andriatafika, Zo Emmanuel; Burgas, Daniel; Temba, Eric Marcel; Torrent, Laura; Cabeza, Mar (2018)
    Despite conservation discourses in Madagascar increasingly emphasizing the role of customary institutions for wildlife management, we know relatively little about their effectiveness. Here, we used semi-structured interviews with 54 adults in eight villages to investigate whether sacred caves and taboos offer conservation benefits for cave-dwelling bats in and around Tsimanampetsotsa National Park, south-west Madagascar. Although some caves were described as sites of spiritual significance for the local communities, most interviewees (c. 76%) did not recognize their present-day sacred status. Similarly, only 22% of the interviewees recognized taboos inhibiting bat hunting and consumption. Legal protection of bats and caves through protected areas was often more widely acknowledged than customary regulations, although up to 30% of the interviewees reported consumption of bats within their communities. Guano extraction was often tolerated in sacred caves in exchange for economic compensation. This may benefit bat conservation by creating incentives for bat protection, although extraction is often performed through destructive and exploitative practices with little benefit for local communities. In view of these results our study questions the extent to which sacred sites, taboos and protected areas offer protection for bats in Madagascar. These results support previous studies documenting the erosion of customary institutions in Madagascar, including the loss of the spiritual values underpinning sacred sites. Given that many Malagasy bats are cave-dwelling species and that most depend on the customary protection of these sites, it is important to obtain a better understanding of the complex interactions between spiritual practices, taboos and protected areas in sustaining bat diversity.
  • Kallijärvi, Jukka; Stratoulias, Vassilis; Virtanen, Kristel; Hietakangas, Ville; Heino, Tapio I.; Saarma, Mart (2012)
  • Iqbal, Sumaiya; Perez-Palma, Eduardo; Jespersen, Jakob B.; May, Patrick; Hoksza, David; Heyne, Henrike O.; Ahmed, Shehab S.; Rifat, Zaara T.; Rahman, M. Sohel; Lage, Kasper; Palotie, Aarno; Cottrell, Jeffrey R.; Wagner, Florence F.; Daly, Mark J.; Campbell, Arthur J.; Lal, Dennis (2020)
    Interpretation of the colossal number of genetic variants identified from sequencing applications is one of the major bottlenecks in clinical genetics, with the inference of the effect of amino acid-substituting missense variations on protein structure and function being especially challenging. Here we characterize the three-dimensional (3D) amino acid positions affected in pathogenic and population variants from 1,330 disease-associated genes using over 14,000 experimentally solved human protein structures. By measuring the statistical burden of variations (i.e., point mutations) from all genes on 40 3D protein features, accounting for the structural, chemical, and functional context of the variations' positions, we identify features that are generally associated with pathogenic and population missense variants. We then perform the same amino acid-level analysis individually for 24 protein functional classes, which reveals unique characteristics of the positions of the altered amino acids: We observe up to 46% divergence of the class-specific features from the general characteristics obtained by the analysis on all genes, which is consistent with the structural diversity of essential regions across different protein classes. We demonstrate that the function-specific 3D features of the variants match the readouts of mutagenesis experiments for BRCA1 and PTEN, and positively correlate with an independent set of clinically interpreted pathogenic and benign missense variants. Finally, we make our results available through a web server to foster accessibility and downstream research. Our findings represent a crucial step toward translational genetics, from highlighting the impact of mutations on protein structure to rationalizing the variants' pathogenicity in terms of the perturbed molecular mechanisms.
  • Djikic, Teodora; Vucicevic, Jelica; Laurila, Jonne; Radi, Marco; Veljkovic, Nevena; Xhaard, Henri; Nikolic, Katarina M. (2020)
    Based on the finding that a central antihypertensive agent with high affinity for I1-type imidazoline receptors ? rilmenidine, shows cytotoxic effects on cultured cancer cell lines, it has been suggested that imidazoline receptors agonists might have a therapeutic potential in the cancer therapy. Nevertheless, potential rilmenidine side effects caused by activation of α-adrenoceptors, or other associated receptors and enzymes, might hinder its therapeutic benefits. Considering that human α-adrenoceptors belong to the rhodopsin-like class A of G-protein-coupled receptors (GPCRs) it is reasonable to assume that imidazolines might have the affinity for other receptors from the same class. Therefore, to investigate possible off-target effects of imidazoline ligands we have prepared a reverse docking protocol on class A GPCRs, using imidazoline ligands and their decoys. To verify our in silico results, three ligands with high scores and three ligands with low scores were tested for antagonistic activity on α2- adrenoceptors.
  • Harju, Jarkko; Vehkaoja, Antti; Lindroos, Ville; Kumpulainen, Pekka; Liuhanen, Sasu; Yli-Hankala, Arvi; Oksala, Niku (2017)
    Alterations in arterial blood oxygen saturation, heart rate (HR), and respiratory rate (RR) are strongly associated with intra-hospital cardiac arrests and resuscitations. A wireless, easy-to-use, and comfortable method for monitoring these important clinical signs would be highly useful. We investigated whether the Nellcor (TM) OxiMask MAX-FAST forehead sensor could provide data for vital sign measurements when located at the distal forearm instead of its intended location at the forehead to provide improved comfortability and easy placement. In a prospective setting, we recruited 30 patients undergoing surgery requiring postoperative care. At the postoperative care unit, patients were monitored for two hours using a standard patient monitor and with a study device equipped with a Nellcor (TM) Forehead SpO(2) sensor. The readings were electronically recorded and compared in post hoc analysis using Bland-Altman plots, Spearman's correlation, and root-mean-square error (RMSE). Bland-Altman plot showed that saturation (SpO(2)) differed by a mean of -0.2 % points (SD, 4.6), with a patient-weighted Spearman's correlation (r) of 0.142, and an RMSE of 4.2 points. For HR measurements, the mean difference was 0.6 bpm (SD, 2.5), r = 0.997, and RMSE = 1.8. For RR, the mean difference was -0.5 1/min (4.1), r = 0.586, and RMSE = 4.0. The SpO(2) readings showed a low mean difference, but also a low correlation and high RMSE, indicating that the Nellcor (TM) saturation sensor cannot reliably assess oxygen saturation at the forearm when compared to finger PPG measurements.
  • Karhula, Sakari S.; Finnilä, Mikko A.; Lammi, Mikko J.; Ylärinne, Janne H.; Kauppinen, Sami; Rieppo, Lassi; Pritzker, Kenneth P. H.; Nieminen, Heikki J.; Saarakkala, Simo (2017)
    Contrast-enhanced micro-computed tomography (CE mu CT) with phosphotungstic acid (PTA) has shown potential for detecting collagen distribution of articular cartilage. However, the selectivity of the PTA staining to articular cartilage constituents remains to be elucidated. The aim of this study was to investigate the dependence of PTA for the collagen content in bovine articular cartilage. Adjacent bovine articular cartilage samples were treated with chondroitinase ABC and collagenase to degrade the proteoglycan and the collagen constituents in articular cartilage, respectively. Enzymatically degraded samples were compared to the untreated samples using CE mu CT and reference methods, such as Fourier-transform infrared imaging. Decrease in the X-ray attenuation of PTA in articular cartilage and collagen content was observed in cartilage depth of 0-13% and deeper in tissue after collagen degradation. Increase in the X-ray attenuation of PTA was observed in the cartilage depth of 13- 39% after proteoglycan degradation. The X-ray attenuation of PTA-labelled articular cartilage in CE mu CT is associated mainly with collagen content but the proteoglycans have a minor effect on the X-ray attenuation of the PTA-labelled articular cartilage. In conclusion, the PTA labeling provides a feasible CE mu CT method for 3D characterization of articular cartilage.
  • Arriga, Nicola; Rannik, Ullar; Aubinet, Marc; Carrara, Arnaud; Vesala, Timo; Papale, Dario (2017)
    Footprint models, which simulate source area for scalar fluxes, are fundamental tools for a correct interpretation of micromoeteorological flux measurements and ecosystem exchange inferred from such data. Over the last two decades models of varying complexity have been developed, but all of them suffer from a significant lack of experimental validation. In this study two different experimental tests have been conducted with the aim of offering validation: a manipulation of the vegetation cover and an artificial tracer emission. In the first case the extension of the flux source has been changed progressively by successive cuts of vegetation, while in the second case by varying the distance of a tracer emission line respect to the measurement point. Results have been used to validate two analytical and a numerical footprint models. The experimental data show a good agreement with footprint models and indicate a limited extension of the flux source area, with approximately 75% of the sources confined within a range of 10-20 times the effective measurement height, i.e. the measurement height above the zero plane displacement. Another interesting result was the strong dependence on the surface roughness of both experimental estimates and numerical simulations of footprint. The effect of surface roughness on experimental results and models outputs was comparable to the effect of atmospheric stability. This indicates that surface roughness and turbulence conditions may play a significant role in source area location, in particular above inhomogeneous surfaces with change in roughness, as in the case of the manipulation experiment. Consequently a careful site specific quantification of these parameters seems to be fundamental to obtain realistic footprint estimates and significantly improve eddy covariance flux interpretation at complex sites.
  • Lokki, A. Inkeri; Aalto-Viljakainen, Tia; Meri, Seppo; Laivuori, Hannele; FINNPEC; Kere, Juha Kalervo (2015)
  • Madauss, Lukas; Zegkinoglou, Ioannis; Muinos, Henrique Vazquez; Choi, Yong-Wook; Kunze, Sebastian; Zhao, Meng-Qiang; Naylor, Carl H.; Ernst, Philipp; Pollmann, Erik; Ochedowski, Oliver; Lebius, Henning; Benyagoub, Abdenacer; Ban-d'Etat, Brigitte; Johnson, A. T. Charlie; Djurabekova, Flyura; Cuenya, Beatriz Roldan; Schleberger, Marika (2018)
    Two-dimensional molybdenum-disulfide (MoS2) catalysts can achieve high catalytic activity for the hydrogen evolution reaction upon appropriate modification of their surface. The intrinsic inertness of the compound's basal planes can be overcome by either increasing the number of catalytically active edge sites or by enhancing the activity of the basal planes via a controlled creation of sulfur vacancies. Here, we report a novel method of activating the MoS2 surface using swift heavy ion irradiation. The creation of nanometer-scale structures by an ion beam, in combination with the partial sulfur depletion of the basal planes, leads to a large increase of the number of low-coordinated Mo atoms, which can form bonds with adsorbing species. This results in a decreased onset potential for hydrogen evolution, as well as in a significant enhancement of the electrochemical current density by over 160% as compared to an identical but non-irradiated MoS2 surface.
  • Pollari, Sirkku; Leivonen, Suvi-Katri; Perälä, Merja; Fey, Vidal; Käkönen, Sanna-Maria; Kallioniemi, Olli (2012)
  • Toivonen, Jarkko; Das, Pratyush; Taipale, Jussi; Ukkonen, Esko (2020)
    Motivation: Position-specific probability matrices (PPMs, also called position-specific weight matrices) have been the dominating model for transcription factor (TF)-binding motifs in DNA. There is, however, increasing recent evidence of better performance of higher order models such as Markov models of order one, also called adjacent dinucleotide matrices (ADMs). ADMs can model dependencies between adjacent nucleotides, unlike PPMs. A modeling technique and software tool that would estimate such models simultaneously both for monomers and their dimers have been missing. Results: We present an ADM-based mixture model for monomeric and dimeric TF-binding motifs and an expectation maximization algorithm MODER2 for learning such models from training data and seeds. The model is a mixture that includes monomers and dimers, built from the monomers, with a description of the dimeric structure (spacing, orientation). The technique is modular, meaning that the co-operative effect of dimerization is made explicit by evaluating the difference between expected and observed models. The model is validated using HT-SELEX and generated datasets, and by comparing to some earlier PPM and ADM techniques. The ADM models explain data slightly better than PPM models for 314 tested TFs (or their DNA-binding domains) from four families (bHLH, bZIP, ETS and Homeodomain), the ADM mixture models by MODER2 being the best on average.
  • Toivonen, Jarkko; Kivioja, Teemu; Jolma, Arttu; Yin, Yimeng; Taipale, Jussi; Ukkonen, Esko (2018)
    In some dimeric cases of transcription factor (TF) binding, the specificity of dimeric motifs has been observed to differ notably from what would be expected were the two factors to bind to DNA independently of each other. Current motif discovery methods are unable to learn monomeric and dimeric motifs in modular fashion such that deviations from the expected motif would become explicit and the noise from dimeric occurrences would not corrupt monomeric models. We propose a novel modeling technique and an expectation maximization algorithm, implemented as software tool MODER, for discovering monomeric TF binding motifs and their dimeric combinations. Given training data and seeds for monomeric motifs, the algorithm learns in the same probabilistic framework a mixture model which represents monomeric motifs as standard position-specific probability matrices (PPMs), and dimeric motifs as pairs of monomeric PPMs, with associated orientation and spacing preferences. For dimers the model represents deviations from pure modular model of two independent monomers, thus making co-operative binding effects explicit. MODER can analyze in reasonable time tens of Mbps of training data. We validated the tool on HT-SELEX and ChIP-seq data. Our findings include some TFs whose expected model has palindromic symmetry but the observed model is directional.
  • Haukka, E.; Kaila-Kangas, L.; Ojajarvi, A.; Saastamoinen, P.; Holtermann, A.; Jorgensen, M. B.; Karppinen, J.; Heliovaara, M.; Leino-Arjas, P. (2015)
    BackgroundMusculoskeletal pain at several sites (multisite pain) is more common than single-site pain. Little is known on its effects on disability pension (DP) retirement. MethodsA nationally representative sample comprised 4071 Finns in the workforce aged 30 to 63. Data (questionnaire, interview, clinical examination) were gathered in 2000-2001 and linked with national DP registers for 2000-2011. Pain during the preceding month in 18 locations was combined into four sites (neck, upper limbs, low back, lower limbs). Hazard ratios (HR) of DP were estimated by Cox regression. ResultsThe HR of any DP (n=477) was 1.6 (95% confidence interval 1.2-2.1) for one, 2.5 (1.9-3.3) for two, 3.1 (2.3-4.3) for three and 5.6 (4.0-7.8) for four pain sites, when adjusted for age and gender. When additionally adjusted for clinically assessed chronic diseases, the HRs varied from 1.4 (1.0-1.8) to 3.5 (2.5-4.9), respectively. When further adjusted for physical and psychosocial workload, education, body mass index, smoking, exercise and sleep disorders, the HRs were 1.3 (0.9-1.7), 1.6 (1.2-2.2), 1.8 (1.3-2.5) and 2.5 (1.8-3.6). The number of pain sites was especially strong in predicting DPs due to musculoskeletal diseases (HRs in the full model; 3.1 to 4.3), but it also predicted DPs due to other somatic diseases (respective HRs 1.3 to 2.3); pain in all four sites was also predictive of DPs due to mental disorders (full model HR 2.2). ConclusionsThe number of pain sites independently predicted DP retirement. Employees with multisite pain may need specific support to maintain their work ability.
  • Dai, Xiaofeng; Yli-Harja, Olli; Lahdesmaki, Harri (2010)
    Background. Revealing protein-DNA interactions is a key problem in understanding transcriptional regulation at mechanistic level. Computational methods have an important role in predicting transcription factor target gene genomewide. Multiple data fusion provides a natural way to improve transcription factor target gene predictions because sequence specificities alone are not sufficient to accurately predict transcription factor binding sites. Methods. Here we develop a new data fusion method to combine multiple genome-level data sources and study the extent to which DNA duplex stability and nucleosome positioning information, either alone or in combination with other data sources, can improve the prediction of transcription factor target gene. Results. Results on a carefully constructed test set of verified binding sites in mouse genome demonstrate that our new multiple data fusion method can reduce false positive rates, and that DNA duplex stability and nucleosome occupation data can improve the accuracy of transcription factor target gene predictions, especially when combined with other genome-level data sources. Cross-validation and other randomization tests confirm the predictive performance of our method. Our results also show that nonredundant data sources provide the most efficient data fusion.
  • Jousi, Mille; Skrifvars, Markus B.; Nelskylä, Annika; Ristagno, Giuseppe; Schramko, Alexey; Nurmi, Jouni (2019)
    Introduction: Screening and correcting reversible causes of cardiac arrest (CA) are an essential part of cardiopulmonary resuscitation (CPR). Point-ofcare (POC) laboratory analyses are used for screening pre-arrest pathologies, such as electrolyte disorders and acid-base balance disturbances. The aims of this study were to compare the intraosseous (10), arterial and central venous POC values during CA and CPR and to see how the CPR values reflect the pre-arrest state. Methods: We performed an experimental study on 23 anaesthetised pigs. After induction of ventricular fibrillation (VF), we obtained POC samples from the 10 space, artery and central vein simultaneously at three consecutive time points. We observed the development of the values during CA and CPR and compared the CPR values to the pre-arrest values. Results: The 10, arterial and venous values changed differently from one another during the course of CA and CPR. Base excess and pH decreased in the venous and 10 samples during untreated VF, but in the arterial samples, this only occurred after the onset of CPR. The 10, arterial and venous potassium values were higher during CPR compared to the pre-arrest arterial values (mean elevations 4.4 mmol/l (SD 0.72), 3.3 mmol/l (0.78) and 2.8 mmol/l (0.94), respectively). Conclusions: A dynamic change occurs in the common laboratory values during CA and CPR. POC analyses of lactate, pH, sodium and calcium within 10 samples are not different from analyses of arterial or venous blood. Potassium values in 10, arterial and venous samples during CPR are higher than the pre-arrest arterial values.
  • Pavon-Jordan, Diego; Abdou, Web; Azafzaf, Hichem; Balaz, Michal; Bino, Taulant; Borg, John J.; Bozic, Luca; Butchart, Stuart H. M.; Clausen, Preben; Sniauksta, Laimonas; Dakki, Mohamed; Devos, Koen; Domsa, Cristi; Encarnacao, Vitor; Etayeb, Khaled; Farago, Sandor; Fox, Anthony D.; Frost, Teresa; Gaudard, Clemence; Georgiev, Valeri; Goratze, Irakli; Hornman, Menno; Keller, Verena; Kostiushyn, Vasiliy; Langendoen, Tom; Ieronymidou, Christina; Lewis, Lesley J.; Lorentsen, Svein-Hakon; Luigujoe, Leho; Meissner, Wlodzimierz; Mikuska, Tibor; Molina, Blas; Musil, Petr; Musilova, Zuzana; Nagy, Szabolcs; Natykanets, Viktor; Nilsson, Leif; Paquet, Jean-Yves; Portolou, Danae; Ridzon, Josef; Santangeli, Andrea; Sayoud, Samir; Sciban, Marko; Stipniece, Antra; Teufelbauer, Norbert; Topic, Goran; Uzunova, Danka; Vizi, Andrej; Wahl, Johannes; Yavuz, Kiraz E.; Zenatello, Marco; Lehikoinen, Aleksi; Lawicki, Lukasz (2020)
    Migratory waterbirds require an effectively conserved cohesive network of wetland areas throughout their range and life-cycle. Under rapid climate change, protected area (PA) networks need to be able to accommodate climate-driven range shifts in wildlife if they are to continue to be effective in the future. Thus, we investigated geographical variation in the relationship between local temperature anomaly and the abundance of 61 waterbird species during the wintering season across Europe and North Africa during 1990-2015. We also compared the spatio-temporal effects on abundance of sites designated as PAs, Important Bird and Biodiversity Areas (IBAs), both, or neither designation (Unlisted). Waterbird abundance was positively correlated with temperature anomaly, with this pattern being strongest towards north and east Europe. Waterbird abundance was higher inside IBAs, whether they were legally protected or not. Trends in waterbird abundance were also consistently more positive inside both protected and unprotected IBAs across the whole study region, and were positive in Unlisted wetlands in southwestern Europe and North Africa. These results suggest that IBAs are important sites for wintering waterbirds, but also that populations are shifting to unprotected wetlands (some of which are IBAs). Such IBAs may therefore represent robust candidate sites to expand the network of legally protected wetlands under climate change in north-eastern Europe. These results underscore the need for monitoring to understand how the effectiveness of site networks is changing under climate change.
  • Peret, Benjamin; Middleton, Alistair M.; French, Andrew P.; Larrieu, Antoine; Bishopp, Anthony; Njo, Maria; Wells, Darren M.; Porco, Silvana; Mellor, Nathan; Band, Leah R.; Casimiro, Ilda; Kleine-Vehn, Juergen; Vanneste, Steffen; Sairanen, Ilkka; Mallet, Romain; Sandberg, Goran; Ljung, Karin; Beeckman, Tom; Benkova, Eva; Friml, Jiri; Kramer, Eric; King, John R.; De Smet, Ive; Pridmore, Tony; Owen, Markus; Bennett, Malcolm J. (2013)
  • Morgunova, Ekaterina; Yin, Yimeng; Jolma, Arttu; Dave, Kashyap; Schmierer, Bernhard; Popov, Alexander; Eremina, Nadejda; Nilsson, Lennart; Taipale, Jussi (2015)
    The mammalian cell cycle is controlled by the E2F family of transcription factors. Typical E2Fs bind to DNA as heterodimers with the related dimerization partner (DP) proteins, whereas the atypical E2Fs, E2F7 and E2F8 contain two DNA-binding domains (DBDs) and act as repressors. To understand the mechanism of repression, we have resolved the structure of E2F8 in complex with DNA at atomic resolution. We find that the first and second DBDs of E2F8 resemble the DBDs of typical E2F and DP proteins, respectively. Using molecular dynamics simulations, biochemical affinity measurements and chromatin immunoprecipitation, we further show that both atypical and typical E2Fs bind to similar DNA sequences in vitro and in vivo. Our results represent the first crystal structure of an E2F protein with two DBDs, and reveal the mechanism by which atypical E2Fs can repress canonical E2F target genes and exert their negative influence on cell cycle progression.
  • Lagström, Sonja; Umu, Sinan Ugur; Lepistö, Maija; Ellonen, Pekka; Meisal, Roger; Christiansen, Irene Kraus; Ambur, Ole Herman; Rounge, Trine B. (2019)
    HPV genomic variability and chromosomal integration are important in the HPV-induced carcinogenic process. To uncover these genomic events in an HPV infection, we have developed an innovative and cost-effective sequencing approach named TaME-seq (tagmentation-assisted multiplex PCR enrichment sequencing). TaME-seq combines tagmentation and multiplex PCR enrichment for simultaneous analysis of HPV variation and chromosomal integration, and it can also be adapted to other viruses. For method validation, cell lines (n = 4), plasmids (n = 3), and HPV16, 18, 31, 33 and 45 positive clinical samples (n = 21) were analysed. Our results showed deep HPV genome-wide sequencing coverage. Chromosomal integration breakpoints and large deletions were identified in HPV positive cell lines and in one clinical sample. HPV genomic variability was observed in all samples allowing identification of low frequency variants. In contrast to other approaches, TaME-seq proved to be highly efficient in HPV target enrichment, leading to reduced sequencing costs. Comprehensive studies on HPV intra-host variability generated during a persistent infection will improve our understanding of viral carcinogenesis. Efficient identification of both HPV variability and integration sites will be important for the study of HPV evolution and adaptability and may be an important tool for use in cervical cancer diagnostics.
  • Kukkurainen, Sampo; Azizi, Latifeh; Zhang, Pingfeng; Jacquier, Marie-Claude; Baikoghli, Mo; von Essen, Magdalena; Tuukkanen, Anne; Laitaoja, Mikko; Liu, Xiaonan; Rahikainen, Rolle; Orlowski, Adam; Jänis, Janne; Määttä, Juha A. E.; Varjosalo, Markku; Vattulainen, Ilpo; Rog, Tomasz; Svergun, Dmitri; Cheng, R. Holland; Wu, Jinhua; Hytönen, Vesa P.; Wehrle-Haller, Bernhard (2020)
    Integrin activation and clustering by talin are early steps of cell adhesion. Membrane-bound talin head domain and kindlin bind to the beta integrin cytoplasmic tail, cooperating to activate the heterodimeric integrin, and the talin head domain induces integrin clustering in the presence of Mn2+. Here we show that kindlin-1 can replace Mn2+ to mediate beta 3 integrin clustering induced by the talin head, but not that induced by the F2-F3 fragment of talin. Integrin clustering mediated by kindlin-1 and the talin head was lost upon deletion of the flexible loop within the talin head F1 subdomain. Further mutagenesis identified hydrophobic and acidic motifs in the F1 loop responsible for beta 3 integrin clustering. Modeling, computational and cysteine crosslinking studies showed direct and catalytic interactions of the acidic F1 loop motif with the juxtamembrane domains of alpha- and beta 3-integrins, in order to activate the beta 3 integrin heterodimer, further detailing the mechanism by which the talin-kindlin complex activates and clusters integrins. Moreover, the F1 loop interaction with the beta 3 integrin tail required the newly identified compact FERM fold of the talin head, which positions the F1 loop next to the inner membrane clasp of the talin-bound integrin heterodimer. This article has an associated First Person interview with the first author of the paper.