Biology subjects

Bos, J. I.

Publications and source records attributed to Bos, J. I..

3 recordsLinked to original sources

bioRxiv2025

The highly conserved aphid effector pair Mp1-Mp58 associates to form an effector complex that targets host trafficking protein VPS52

Pathogen and pest effectors play a crucial role in manipulating plant biological processes, facilitating infection and infestation. While pathogens and pests secrete repertoires of effectors into their host plants, most effector function studies focus on characterising individual proteins. We previously identified a genetically linked and co-regulated gene pair in the aphid Myzus persicae encoding effectors Mp1 and Mp58. Here, we explored the functional link between these effectors. We used ectopic expression assays in Nicotiana benthamiana followed by co-immunoprecipitation assays and confocal microscopy to explore effector-effector and effector-target interactions and their subcellular localisation. We produced recombinant proteins to validate effector interactions and used computational modelling to predict effector complex 3D structures. We revealed that effectors Mp1 and Mp58 interact in planta and in vitro and likely form an oligomeric complex. Both effectors associate with the host target Vacuolar Protein Sorting associated Protein 52 (VPS52) to form an Mp1-Mp58-VPS52 complex which localises at vesicle-like structures. Our findings point to effector complex formation in plant-insect interactions and highlight a further layer of complexity in the molecular dialogue between plants and insects. Our work also shows the importance of considering the context in which effectors may function within a larger effector repertoire.

plant biology↗

bioRxiv2023

Computational prediction of structure, function and interaction of aphid salivary effector proteins

Similar to plant pathogens, phloem-feeding insects such as aphids deliver effector proteins inside their hosts that act to promote host susceptibility and enable feeding and infestation. Despite exciting progress towards identifying and characterizing effector proteins from these insects, their functions remain largely unknown. The recent ground-breaking development in protein structure prediction algorithms combined with the availability of proteomics and transcriptomic datasets for agriculturally important pests, such as the aphid Myzus persicae (green peach aphid), provides new opportunities to explore the structural and functional diversity of effector repertoires. In this study, we sought to gain insight into the the M. persicae effector repertoire by predicting and analysing the structures of a set of 71 effector candidate proteins. We used two protein structure prediction methods, AlphaFold and OmegaFold, which produced mutually consistent results. We observed a wide continuous spectrum of sizes and structures among the effector candidates, from disordered proteins to globular enzymes. We made use of the structural information and state-of-the-art computational methods to predict M. persicae effector protein properties, including function and interaction with host plant proteins. Overall, our investigation provides novel insights into the structure, function, and interaction prediction of aphid effector repertoires and will guide the necessary experimental characterization to address new hypotheses.

biochemistry↗

bioRxiv2020

Stressful times in a climate crisis: how will aphids respond to more frequent drought?

AimAphids are abundant in natural and managed vegetation, supporting a diverse community of organisms and causing damage to agricultural crops. Using a meta-analysis approach, we aimed to advance understanding of how increased drought incidence will affect this ecologically and economically important insect group, and to characterise the underlying mechanisms. LocationGlobal. Time period1958-2020. Major taxa studiedAphids. MethodsWe used qualitative and quantitative synthesis techniques to determine whether drought stress has a negative, positive, or null effect on aphid fitness. We examined these effects in relation to 1) aphid biology, 2) the aphid-plant. species combination. We compiled two datasets: 1) a "global" dataset (n = 55 from 55 published studies) comprising one pooled effect size per study, and 2) an "expanded" dataset (n = 93) containing multiple datapoints per study, separated into different measures of aphid fitness but pooled across aphid-plant combinations. Where reported, we extracted data on the effect of drought on plant vigour, and plant tissue concentrations of nutrients and defensive compounds, to capture the potential causes of aphid responses. ResultsAcross all studies ("global" dataset), drought stress had a negative effect on aphid fitness: Hedges g = -0.57; 95% confidence interval (CI95) = {+/-}0.31. The "expanded" dataset indicated that, on average, drought stress reduced aphid fecundity (g = - 0.98; CI95 = {+/-}0.50) and increased development time (g = 1.13; CI95 = {+/-}1.02). Furthermore, drought stress had a negative impact on plant vigour (g = -7.06; CI95 = {+/-}2.86) and increased plant concentrations of defensive chemicals (g = 3.14; CI95 = {+/-}3.14). Main conclusionsAphid fitness is typically reduced under drought, associated with reduced plant vigour and increased chemical defence in drought-stressed plants. We propose a conceptual model to predict drought effects on aphid fitness in relation to plant vigour and defence.

ecology↗