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Communications Biology May 2021Transmembrane conductance of small uncharged solutes such as glycerol typically occurs through aquaglyceroporins (Glps), which are commonly encoded by multiple genes in...
Transmembrane conductance of small uncharged solutes such as glycerol typically occurs through aquaglyceroporins (Glps), which are commonly encoded by multiple genes in metazoan organisms. To date, however, little is known concerning the evolution of Glps in Crustacea or what forces might underly such apparent gene redundancy. Here, we show that Glp evolution in Crustacea is highly divergent, ranging from single copy genes in species of pedunculate barnacles, tadpole shrimps, isopods, amphipods and decapods to up to 10 copies in diplostracan water fleas although with monophyletic origins in each lineage. By contrast the evolution of Glps in Copepoda appears to be polyphyletic, with surprisingly high rates of gene duplication occurring in a genera- and species-specific manner. Based upon functional experiments on the Glps from a parasitic copepod (Lepeophtheirus salmonis), we show that such lineage-level gene duplication and splice variation is coupled with a high rate of neofunctionalization. In the case of L. salmonis, splice variation of a given gene resulted in tissue- or sex-specific expression of the channels, with each variant evolving unique sites for protein kinase C (PKC)- or protein kinase A (PKA)-regulation of intracellular membrane trafficking. The combined data sets thus reveal that mutations favouring a high fidelity control of intracellular trafficking regulation can be a selection force for the evolution and retention of multiple Glps in copepods.
Topics: Animals; Aquaglyceroporins; Biological Evolution; Copepoda; Crustacea; Evolution, Molecular; Genetic Variation; Multigene Family; Phylogeny; Protein Isoforms
PubMed: 34059783
DOI: 10.1038/s42003-021-01921-9 -
The New Phytologist Sep 2021Leaves interact with a wealth of microorganisms. Among these, fungi are highly diverse and are known to contribute to plant health, leaf senescence and early...
Leaves interact with a wealth of microorganisms. Among these, fungi are highly diverse and are known to contribute to plant health, leaf senescence and early decomposition. However, patterns and drivers of the seasonal dynamics of foliar fungal communities are poorly understood. We used a multifactorial experiment to investigate the influence of warming and tree genotype on the foliar fungal community on the pedunculate oak Quercus robur across one growing season. Fungal species richness increased, evenness tended to decrease, and community composition strongly shifted during the growing season. Yeasts increased in relative abundance as the season progressed, while putative fungal pathogens decreased. Warming decreased species richness, reduced evenness and changed community composition, especially at the end of the growing season. Warming also negatively affected putative fungal pathogens. We only detected a minor imprint of tree genotype and warming × genotype interactions on species richness and community composition. Overall, our findings demonstrate that warming plays a larger role than plant genotype in shaping the seasonal dynamics of the foliar fungal community on oak. These warming-induced shifts in the foliar fungal community may have a pronounced impact on plant health, plant-fungal interactions and ecosystem functions.
Topics: Ecosystem; Genotype; Mycobiome; Quercus; Seasons
PubMed: 33960441
DOI: 10.1111/nph.17434 -
Integrative and Comparative Biology Nov 2021Many marine invertebrates have complex life histories that begin with a planktonic larval stage. Similar to other plankton, these larval invertebrates often possess...
Many marine invertebrates have complex life histories that begin with a planktonic larval stage. Similar to other plankton, these larval invertebrates often possess protruding body extensions, but their function beyond predator deterrence is not well-documented. For example, the planktonic nauplii of crustaceans have spines. Using the epibiotic pedunculate barnacle Octolasmis spp., we investigated how the dorsal thoracic spine affects swimming and fluid disturbance by comparing nauplii with their spines partially removed against those with intact spines. Our motion analysis showed that amputated Octolasmis spp. swam slower, in jerkier trajectories, and were less efficient per stroke cycle than those with intact spines. Amputees showed alterations in limb beat pattern: larger beat amplitude, increased phase lag, and reduced contralateral symmetry. These changes might partially help increase propulsive force generation and streamline the flow, but were insufficient to restore full function. Particle image velocimetry further showed that amputees had a larger relative area of influence, implying elevated risk by rheotactic predator. Body extensions and their interactions with limb motion play important biomechanical roles in shaping larval performance, which likely influences the evolution of form.
Topics: Animals; Biomechanical Phenomena; Larva; Rheology; Spine; Swimming; Thoracica
PubMed: 33905496
DOI: 10.1093/icb/icab036 -
Tree Physiology Jul 2021Research on wood phenology has mainly focused on reactivation of the cambium in spring. In this study we investigated if summer drought advances cessation of wood...
Research on wood phenology has mainly focused on reactivation of the cambium in spring. In this study we investigated if summer drought advances cessation of wood formation and if it has any influence on wood structure in late successional forest trees of the temperate zone. The end of xylogenesis was monitored between August and November in stands of European beech and pedunculate oak in Belgium for two consecutive years, 2017 and 2018, with the latter year having experienced an exceptional summer drought. Wood formation in oak was affected by the drought, with oak trees ceasing cambial activity and wood maturation about 3 weeks earlier in 2018 compared with 2017. Beech ceased wood formation before oak, but its wood phenology did not differ between years. Furthermore, between the 2 years, no significant difference was found in ring width, percentage of mature fibers in the late season, vessel size and density. In 2018, beech did show thinner fiber walls, whereas oak showed thicker walls. In this paper, we showed that summer drought can have an important impact on late season wood phenology xylem development. This will help to better understand forest ecosystems and improve forest models.
Topics: Droughts; Ecosystem; Seasons; Trees; Wood; Xylem
PubMed: 33616191
DOI: 10.1093/treephys/tpaa175 -
Tree Physiology Jul 2021We explored the timing of spring xylogenesis and its potential drivers in homogeneous mature forest stands in a temperate European region. Three species with contrasting...
We explored the timing of spring xylogenesis and its potential drivers in homogeneous mature forest stands in a temperate European region. Three species with contrasting leaf development dynamics and wood anatomy were studied: European beech, silver birch and pedunculate oak. Detailed phenological observations of xylogenesis and leaf phenology were performed from summer 2017 until spring 2018. Cambium reactivation (CR) occurred before the buds of oak and birch were swollen, whereas these two phenological phases were concurrent for beech. On the other hand, initial earlywood vessels were fully differentiated (FDIEV) after leaf unfolding for all three species. Timing of CR was correlated to average ring-width of the last 10 years (2008-17), tree diameter and, partially, with tree age. In addition, the timing of FDIEV was correlated to tree age and previous year's autumn phenology, i.e., timing of wood growth cessation and onset of leaf senescence. Multivariate models could explain up to 68% of the variability of CR and 55% of the variability of FDIEV. In addition to the 'species' factor, the variability could be explained by ca 30% by tree characteristics and previous year's autumn phenology for both CR and FDIEV. These findings are important to better identify which factors (other than environment) can be driving the onset of the growing season, and highlight the influence of tree growth characteristics and previous year's phenology on spring wood phenology, wood formation and, potentially, forest production.
Topics: Fagus; Plant Leaves; Quercus; Seasons; Trees
PubMed: 33367844
DOI: 10.1093/treephys/tpaa171 -
Phytochemical Analysis : PCA Sep 2021Two species of oak are dominant in French forests: pedunculate oak (Quercus robur L.) and sessile oak (Quercus petraea Liebl.). Differentiating oak species is difficult,...
INTRODUCTION
Two species of oak are dominant in French forests: pedunculate oak (Quercus robur L.) and sessile oak (Quercus petraea Liebl.). Differentiating oak species is difficult, since features such as morphological characters, geographical origin and grain are not always relevant. Even if the former is generally richer in tannin compounds while the latter is often richer in aromatic compounds, the intra-species variability is high. The characterisation of the oak species remains a suitable indicator of the molecular composition and quality of the wood.
OBJECTIVES
The aim of this study was to determine differentiating molecules allowing oak species identification in order to assist in a suitable wood selection for a better oak tree valorisation since the selection of the oak wood to be used in the production of barrels plays an essential role in wine ageing.
MATERIALS AND METHODS
Oak wood samples were collected both in forests and in cooperage timber yards. An untargeted metabolomic approach using ultra-high-pressure liquid chromatography qualitative time-of-flight high-resolution mass spectrometry (UHPLC-Q-TOF-HRMS) associated to multivariate statistical analyses (hierarchical ascendant clustering and partial least squares discriminant analysis) was implemented to determine molecular markers of oak species.
RESULTS
Heartwood was identified as the suitable wood part to distinguish oak species. Discriminating molecules did not depend on the sample set. The pedunculate species showed overexpression of bartogenic derivatives while sessile oak presented a higher content in oak lactone precursors and in quercotriterpenosids.
CONCLUSION
The developed method allowed the identification of relevant compounds for oak species identification to a better wood valorisation and selection.
Topics: Chromatography, High Pressure Liquid; Mass Spectrometry; Quercus; Wine; Wood
PubMed: 33197960
DOI: 10.1002/pca.3013 -
Zootaxa May 2020Tibetyrus formicarius Yin Lin, gen. et sp. nov., a new myrmecophilous genus and species of the pselaphine tribe Tyrini, is described from southeastern Xizang, China....
Tibetyrus formicarius Yin Lin, gen. et sp. nov., a new myrmecophilous genus and species of the pselaphine tribe Tyrini, is described from southeastern Xizang, China. Three adults were collected in nests of a Formica ant species (Hymenoptera: Formicidae) at an altitude of 3,485 m. Tibetyrus is similar to Megatyrus Hlaváč Nomura in sharing the basally pedunculate maxillary palpi that lack an apical cone on the fourth palpomeres. Nevertheless, it can be readily separated from the latter and all other genera of the tribe by its unique suite of morphological features as well as a highly recognizable habitus.
Topics: Animal Distribution; Animal Structures; Animals; Ants; China; Coleoptera
PubMed: 33056502
DOI: 10.11646/zootaxa.4786.1.10 -
Insects Oct 2020The oak lace bug (OLB), (Hemiptera: Tingidae), was first identified as an invasive pest in Europe in northern Italy in 2000 and since then it has spread rapidly,...
The oak lace bug (OLB), (Hemiptera: Tingidae), was first identified as an invasive pest in Europe in northern Italy in 2000 and since then it has spread rapidly, attacking large forested areas in European countries. The OLB is a cell sap-sucking insect that is native to North America, with spp. as its main host. Its rapid expansion, successful establishment in invaded countries, and observations of more damage to hosts compared to native areas are most likely due to a lack of natural enemies, pathogens and competitors. In its native area, various natural enemies of OLBs have been identified; however, little is known about the occurrence and impact of OLB pathogens. None of the pathogenic fungi found on OLBs in natural conditions have been identified until now. In this study, we provide evidence of four entomopathogenic fungi that are naturally occurring on invasive OLBs found in infested pedunculate oak forests in eastern Croatia. On the basis of their morphology and multilocus molecular phylogeny, the fungi were identified as , , and . The sequences generated for this study are available from GenBank under the accession numbers MT004817-MT004820, MT004833-MT004835, MT027501-MT27510, and MT001936-MT0011943. These pathogenic species could facilitate biological control strategies against OLBs.
PubMed: 33036392
DOI: 10.3390/insects11100679 -
Evolutionary Applications Oct 2020Understanding how tree species will respond to a future climate requires reliable and quantitative estimates of intra-specific variation under current climate...
Assessing adaptive and plastic responses in growth and functional traits in a 10-year-old common garden experiment with pedunculate oak ( L.) suggests that directional selection can drive climatic adaptation.
Understanding how tree species will respond to a future climate requires reliable and quantitative estimates of intra-specific variation under current climate conditions. We studied three 10-year-old common garden experiments established across a rainfall and drought gradient planted with nearly 10,000 pedunculate oak ( L.) trees from ten provenances with known family structure. We aimed at disentangling adaptive and plastic responses for growth (height and diameter at breast height) as well as for leaf and wood functional traits related to adaptation to dry environments. We used restricted maximum likelihood approaches to assess additive genetic variation expressed as narrow-sense heritability (h), quantitative trait differentiation among provenances (Q), and genotype-by-environment interactions (GxE). We found strong and significant patterns of local adaptation in growth in all three common gardens, suggesting that transfer of seed material should not exceed a climatic distance of approximately 1°C under current climatic conditions, while transfer along precipitation gradients seems to be less stringent. Moreover, heritability reached 0.64 for tree height and 0.67 for dbh at the dry margin of the testing spectrum, suggesting significant additive genetic variation of potential use for future selection and tree breeding. GxE interactions in growth were significant and explained less phenotypic variation than origin of seed source (4% versus 10%). Functional trait variation among provenances was partly related to drought regimes at provenances origins but had moderate explanatory power for growth. We conclude that directional selection, either naturally or through breeding, is the most likely and feasible outcome for pedunculate oak to adapt to warmer and drier climate conditions in the future.
PubMed: 33005231
DOI: 10.1111/eva.13034 -
Proceedings. Biological Sciences Sep 2020Insects and pathogens frequently exploit the same host plant and can potentially impact each other's performance. However, studies on plant-pathogen-insect interactions...
Insects and pathogens frequently exploit the same host plant and can potentially impact each other's performance. However, studies on plant-pathogen-insect interactions have mainly focused on a fixed temporal setting or on a single interaction partner. In this study, we assessed the impact of time of attacker arrival on the outcome and symmetry of interactions between aphids (), powdery mildew (), and caterpillars () feeding on pedunculate oak, , and explored how single versus multiple attackers affect oak performance. We used a multifactorial greenhouse experiment in which oak seedlings were infected with either zero, one, two, or three attackers, with the order of attacker arrival differing among treatments. The performances of all involved organisms were monitored throughout the experiment. Overall, attackers had a weak and inconsistent impact on plant performance. Interactions between attackers, when present, were asymmetric. For example, aphids performed worse, but powdery mildew performed better, when co-occurring. Order of arrival strongly affected the outcome of interactions, and early attackers modified the strength and direction of interactions between later-arriving attackers. Our study shows that interactions between plant attackers can be asymmetric, time-dependent, and species specific. This is likely to shape the ecology and evolution of plant-pathogen-insect interactions.
Topics: Animals; Aphids; Ascomycota; Host-Pathogen Interactions; Insecta; Plant Diseases; Quercus
PubMed: 32962544
DOI: 10.1098/rspb.2020.1303