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Invasive alien species (IAS) are a key driver of global biodiversity loss. Reducing their spread and impact is a target of the Sustainable Development Goals (SDG target 15.8) and of the EU IAS Regulation 1143/2014. The use of citizen science offers various benefits to alien species (AS) decision making and to society, since public participation in research and management boosts awareness, engagement and scientific literacy and can reduce conflict in IAS management. We report the results of a survey on AS citizen science initiatives within the framework of European Cooperation in Science and Technology (COST) Action Alien-CSI. We gathered metadata on 103 initiatives across 41 countries, excluding general biodiversity reporting portals, spanning from 2005 to 2020, offering the most comprehensive account of AS citizen science initiatives on the continent to date. We retrieved information on project scope, policy relevance, engagement methods, data capture, data quality and data management, methods and technologies applied and performance indicators such as the number of records coming from projects, the numbers of participants and publications. The 103 initiatives were unevenly distributed geographically, with countries with a tradition of CS showing more active projects. The majority of projects were contributory and were run at a national scale, targeting the general public, alien plants and insects, and terrestrial ecosystems. Most projects focused on collecting species presence or abundance data, aiming to map presence and spread. As 75% of the initiatives specifically collected data on IAS of Union Concern, citizen science in Europe is of high policy relevance. Despite this, only half of the projects indicated sustainable funding. Nearly all projects had validation in place to verify species identifications. Strikingly, only about one third of the projects shared their data to open data repositories such as the Global Biodiversity Information facility or the European Alien Species Information Network. Moreover, many did not adhere to the principles of FAIR data management. Based on this dataset, we offer suggestions to strengthen the network of IAS citizen science projects and to foster knowledge exchange among citizens, scientists, managers, policy-makers, local authorities, and other stakeholders.

Sexual selection theory has proven to be fundamental to our understanding of the male-female 15 (sperm-egg) interactions that characterise fertilisation. However, sexual selection does not operate 16 in a void and abiotic environmental factors have been shown to modulate the outcome of pre17 copularory sexual interactions. Environmental modulation of post-copulatory interactions are 18 particularly likely because the form and function of primary reproductive traits appears to be acutely 19 sensitive to temperature stress. Here we report the effects of developmental temperature on female 20 reproductive architecture and the interaction between male and female developmental 21 temperature on the outcome of sperm competition in the bruchid beetle Callosobruchus maculatus. 22 When females were reared at developmental temperatures above and below typical temperatures 23 the bursa copulatrix (site of spermatophore deposition) were smaller and, were either shorter and 24 broader (high temperatures) or longer and thinner (low temperatures) than those reared at 25 intermediate temperatures. Males and females reared at low developmental temperatures were 26 less likely to mate than those reared at higher temperatures. Where copulation occurred, females 27 reared at the highest temperature copulated for longest, whilst males reared at the lowest 28 temperature spent longer in copula. Male developmental temperature had a significant impact on 29 the outcome of sperm competition: males reared at 17oC were largely unsuccessful in sperm 30 competition against control (27oC) males, although some of the variation in the outcome of sperm 31 competition was a product of the interaction between male and female developmental 32 temperature. Our results demonstrate that male-female interactions that characterise pre- and post33 copulatory outcomes are sensitive to developmental temperature and that plasticity in cryptic 34 female preferences could lead to heterogeneous selection on the male reproductive phenotype.

Plasmodium falciparum is the most virulent causative agent of malaria in man accounting for 80% of all malarial infections and 90% of the one million annual deaths attributed to malaria. P. falciparum is a unicellular, Apicomplexan parasite, that spends part of its lifecycle in the mosquito and part in man and it has evolved a special form of motility that enables it to burrow into animal cells, a process termed "host cell invasion". The acute, life threatening, phase of malarial infection arises when the merozoite form of the parasite undergoes multiple cycles of red blood cell invasion and rapid proliferation. Here, we discuss the molecular machinery that enables malarial parasites to invade red blood cells and we focus particularly on the ATP-driven acto-myosin motor that powers invasion.

Myosin-10 is an actin-based molecular motor that participates in essential intracellular processes such as filopodia formation/extension, phagocytosis, cell migration, and mitotic spindle maintenance. To study this motor protein's mechano-chemical properties, we used a recombinant, truncated form of myosin-10 consisting of the first 936 amino acids, followed by a GCN4 leucine zipper motif, to force dimerization. Negative-stain electron microscopy reveals that the majority of molecules are dimeric with a head-to-head contour distance of ∼50 nm. In vitro motility assays show that myosin-10 moves actin filaments smoothly with a velocity of ∼310 nm/s. Steady-state and transient kinetic analysis of the ATPase cycle shows that the ADP release rate (∼13 s(-1)) is similar to the maximum ATPase activity (∼12-14 s(-1)) and therefore contributes to rate limitation of the enzymatic cycle. Single molecule optical tweezers experiments show that under intermediate load (∼0.5 pN), myosin-10 interacts intermittently with actin and produces a power stroke of ∼17 nm, composed of an initial 15-nm and subsequent 2-nm movement. At low optical trap loads, we observed staircase-like processive movements of myosin-10 interacting with the actin filament, consisting of up to six ∼35-nm steps per binding interaction. We discuss the implications of this load-dependent processivity of myosin-10 as a filopodial transport motor.

Stable, single alpha-helix (SAH) domains are widely distributed in the proteome, including in myosins, but their functions are unknown. To test whether SAH domains can act as levers, we replaced four of the six calmodulin-binding IQ motifs in the levers of mouse myosin 5a (Myo5) with the putative SAH domain of Dictyostelium myosin MyoM of similar length. The SAH domain was inserted between the IQ motifs and the coiled coil in a Myo5 HMM construct in which the levers were truncated from six to two IQ motifs (Myo5–2IQ). Electron microscopy of this chimera (Myo5–2IQ-SAH) showed the SAH domain was straight and 17 nm long as predicted, restoring the truncated lever to the length of wild-type (Myo5–6IQ). The powerstroke (of 21.5 nm) measured in the optical trap was slightly less than that for Myo5–6IQ but much greater than for Myo5–2IQ. Myo5–2IQ-SAH moved processively along actin at physiological ATP concentrations with similar stride and run lengths to Myo5–6IQ in in-vitro single molecule assays. In comparison, Myo5–2IQ is not processive under these conditions. Solution biochemical experiments indicated that the rear head did not mechanically gate the rate of ADP release from the lead head, unlike Myo5–6IQ. These data show that the SAH domain can form part of a functional lever in myosins, although its mechanical stiffness might be lower. More generally, we conclude that SAH domains can act as stiff structural extensions in aqueous solution and this structural role may be important in other proteins.

This chapter focuses on the single molecule studies of myosins and specifically research work with myosin II and myosin V. Single molecule studies of actomyosin, the molecular motor system of actin and myosin, have been at the forefront in terms of technology development and applying new and emerging techniques to address highly specific questions of how it works. Much of what we know about the mechanism by which myosin produces force and movement stems from early structural, mechanical, and biochemical studies performed using single muscle fibers from frogs and purified proteins from rabbits. Single molecule approaches have made a major impact in obtaining an increasingly clear picture of how myosin works at the level of molecular rearrangements during the ATPase cycle. Many of these methods are broadly applicable to other fields. The single molecule techniques originally devised to study actomyosin from muscle have opened up an entire field of science that allows biophysicists to make major contributions to our understanding of cell motility and cell biology. In vitro motility assays enable actomyosin motility to be reconstituted from purified component molecules. Rhodamine-phalloidin-labeled actin filaments can be visualized by fluorescence microscopy as they move on a microscope coverslip surface that has been coated with myosin or one of its proteolytic subfragments.

Optical tweezers have been used extensively to measure the mechanical properties of individual biological molecules. Over the past 10-15 years optical trapping studies have revealed important information about the way in which motor proteins convert chemical energy to mechanical work. This paper focuses on studies of the acto-myosin motor system that is responsible for muscle contraction and a host of other cellular motilities. Myosin works by binding to filamentous actin, pulling and then releasing. Each cycle of interaction produces a few nanometres movement and a few piconewtons force. Individual interactions can be observed directly by holding an individual actin filament between two optically trapped microspheres and positioning it in the immediate vicinity of a single myosin motor. When the chemical fuel (adenosine triphosphate or ATP) is present the myosin undergoes repeated cycles of interaction with the actin filament producing square-wave like displacements and forces. Analysis of optical trapping data sets enables the size and timing of the molecular motions to be deduced.

We have determined the kinetic and motile properties of a myosin 5a HMM construct in which four calmodulin-binding IQ motifs are replaced by the putative single alpha helical domain (SAH) of similar length from Dictyostelium myosin, MyoM. Electron microscopy of this chimera showed that the SAH domain was straight and 17 nm long as predicted, restoring the truncated lever to the length of wild type (Myo5-6IQ). The powerstroke (21.5 nm) measured in the optical trap was slightly less than that for Myo5-6IQ (25 nm) but much greater than for Myo5-2IQ (10 nm). Myo5-2IQ-SAH moves processively along actin at physiological ATP concentrations with similar stride length to Myo5-6IQ in TIRF microscopy assays, and the average run length was also similar. Stopped-flow fluorescence experiments indicated that unlike WT Myo5-6IQ the rear head did not mechanically gate the rate of ADP release from the lead head of the chimera and the rate of ADP dissociation was the same from both heads. These data show that the SAH domain can form part of a functional lever in myosins although its bending stiffness might be lower. We conclude that SAH domains can act as mechanically-competent structural extensions in physiological conditions and that gated dissociation of ADP from the lead head of myosin 5 is not required for processive movement.Funded by BBSRC BB/C004906/1 (MP, PJK and TGB), an Underwood fund grant (MP, PJK and JRS), Wellcome Trust vacation studentship (SMJ), NIH EB00209 (HDW), NIH NIDCD 009335 (EF) and intramural funds from NHLBI (JRS).

Funder: Royal Entomological Society; Id: http://dx.doi.org/10.13039/100013849, Funder: Rural & Environment Science & Analytical Services Division of the Scottish Government, Funder: Alexander von Humboldt Foundation; Id: http://dx.doi.org/10.13039/100005156, Funder: Department of Agriculture, Environment & Rural Affairs, Funder: Center for Environmental and Sustainability Research, 1. Entomology is key to understanding terrestrial and freshwater ecosystems at a time of unprecedented anthropogenic environmental change, and offers substantial untapped potential to benefit humanity in a variety of ways, from improving agricultural practices to managing vector-borne diseases and inspiring technological advances. 2. We identified high priority challenges for entomology using an inclusive, open, and democratic four-stage prioritisation approach, conducted among the membership and affiliates (hereafter ‘members’) of the UK-based Royal Entomological Society (RES). 3. A list of 710 challenges was gathered from 189 RES members. Thematic analysis was used to group suggestions, followed by an online vote to determine initial priorities, which were subsequently ranked during an online workshop involving 37 participants. 4. The outcome was a set of 61 priority challenges within four groupings of related themes: (i) ‘Fundamental Research’ (themes: Taxonomy, ‘Blue Skies’ [defined as research ideas without immediate practical application], Methods and Techniques); (ii) ‘Anthropogenic Impacts and Conservation’ (themes: Anthropogenic Impacts, Conservation Options); (iii) ‘Uses, Ecosystem Services and Disservices’ (themes: Ecosystem Benefits, Technology and Resources [use of insects as a resource, or as inspiration], Pests); (iv) ‘Collaboration, Engagement and Training’ (themes: Knowledge Access, Training and Collaboration, Societal Engagement). 5. Priority challenges encompass research questions, funding objectives, new technologies, and priorities for outreach and engagement. Examples include training taxonomists, establishing a global network of insect monitoring sites, understanding the extent of insect declines, exploring roles of cultivated insects in food supply chains, and connecting professional with amateur entomologists. Responses to different challenges could be led by amateur and professional entomologists, at all career stages. 6. Overall, the challenges provide a diverse array of options to inspire and initiate entomological activities, and reveal the potential of entomology to contribute to addressing global challenges related to human health and well-being, and environmental change.

Recent cell biological studies of myosin-10 have revealed that myosin-10 is essential to cellular processes such as filopodia extensions and phagocytosis. Steady-state and transient kinetic biochemical studies of the ATPase cycle of a single-headed, subfragment-1 like (S1), construct of myosin-10 show that it has an intermediate duty-cycle ratio. It remains tightly bound to actin for about 16% of its total ATPase cycle time but spends around 90% associated with actin in both weak and strongly bound states. Furthermore, the acto-myosin-10-S1 complex has two ADP bound states and a surprisingly low affinity for actin, comparable to that of the rigor complex between actin and skeletal muscle myosin II. To study the mechano-chemical coupling of myosin-10, we used the actin filament sliding assay and a dual-beam, optical tweezers apparatus to perform single molecule mechanical studies. For these studies we used a two-headed, heavy meromyosin-like (HMM) construct of myosin-10 that contained a leucine-zipper at the C-terminal end to force dimerization. The actin filament gliding assay showed that myosin-10-HMM moves filaments at a velocity of ∼125 nm s-1. This is similar to the speed of intact, GFP-tagged, myosin-10 moving within filopodia of live mammalian cells (∼140 nm s-1) measured by TIRF microscopy. Optical trapping results showed that the average powerstroke size was ∼10 nm, with the rate of ATP binding of ∼1.3 μM-1 s-1. In most of the raw data traces, we observed displacements of unitary size, however at low ATP concentrations (2 μM) we also observed a number of interactions that exhibited multiple, staircase-like movements consisting of up to 3 steps per binding interaction. This behaviour is characteristic of a processive molecular motor. We will discuss these measurements in the context of mechano-chemical coupling and the functional significance in the living cell.

Myosin-10 is an actin based motor that localizes to actin rich areas within the cell and carries cargos including netrin receptors and β integrins. Using transient kinetic and single molecule assays, a number of groups have shown that myosin-10 can act as a processivemotor, capable of translocating along actin as a single molecule. However, both the mechanical and kinetic parameters are quite diverse amongst different groups (Kerber & Cheney 2011, J. Cell Sci. 124:3733-3741 and references therein). Negative stain electron microscopy and single particle image processing performed using a truncated myosin-10 construct (1 - 940 a.a.) containing a leucine-zipper at the C-terminal end confirmed dimerization of the molecule with a distance between motor domains of ∼50 nm. When bound to F-actin, the myosin-10 lever arm makes a shallower angle with respect to the filament axis than seen for acto-myosin-5 or acto-myosin-2. In vitro actin gliding assays showed myosin-10-HMM moved F-actin at ∼410 nm.s−1 similar to the speed of GFP-tagged, intact myosin-10 we observed moving within filopodia of live mammalian cells (∼600 nm.s−1) using TIRF microscopy. Optical trapping experiments revealed the average work-stroke size was ∼17 nm with a single actomyosin-10 stiffness of ∼0.4 pN.nm−1 and an ADP-release limited detachment rate of ∼13 s−1. In most raw data traces, we observed unitary displacements, however at low [ATP] (