The neural mechanisms of fear-associated thermoregulation remain unclear. Innate fear odor 2-methyl-2-thiazoline (2MT) elicits rapid hypothermia and elevated tail temperature, indicative of ...vasodilation-induced heat dissipation, in wild-type mice, but not in mice lacking Trpa1-the chemosensor for 2MT. Here we report that Trpa1
mice show diminished 2MT-evoked c-fos expression in the posterior subthalamic nucleus (PSTh), external lateral parabrachial subnucleus (PBel) and nucleus of the solitary tract (NTS). Whereas tetanus toxin light chain-mediated inactivation of NTS-projecting PSTh neurons suppress, optogenetic activation of direct PSTh-rostral NTS pathway induces hypothermia and tail vasodilation. Furthermore, selective opto-stimulation of 2MT-activated, PSTh-projecting PBel neurons by capturing activated neuronal ensembles (CANE) causes hypothermia. Conversely, chemogenetic suppression of vGlut2
neurons in PBel or PSTh, or PSTh-projecting PBel neurons attenuates 2MT-evoked hypothermia and tail vasodilation. These studies identify PSTh as a major thermoregulatory hub that connects PBel to NTS to mediate 2MT-evoked innate fear-associated hypothermia and tail vasodilation.
Ocean litter is of growing global concern, and its impacts on marine environments and ecosystems are expected to increase further this century. From a management perspective, natural drifting of ...macro ocean litter to or near the coast may have a relatively easier opportunity to be cleaned up directly from land, which then helps eliminate litter sufficiently and reduces the associated societal costs. However, quantitative descriptions both of the potential arrival areas of accumulation and of the cumulative impacts of ocean litter and services are lacking. The wind is critical to restructuring litter distributions in locations greatly different from those within the gyres where litter is typically found, prompting strong concerns regarding previously ignored areas, especially the equatorial zone and northern polar regions. As the windage increases, litter is transported across oceans, and polar oceans would become a litter sink instead of a source when litter is simulated to originate from both offshore and coastal areas. Different proportions of offshore- and coastal-source litter exhibit different terminal configurations, including floating offshore, floating near the coast and washed ashore. Notably, depending on windage, 78.4%-94.0% and 54.1%-56.1% offshore- and coastal-source litter continue moving in the oceans. Furthermore, important consequences associated with global marine biodiversity priority areas and litter accumulation are identified, as are substantial increases in influences on phytoplankton biomass with increasing windage. The results not only improve our understandings of macro ocean litter accumulation but also reveal opportunities for proactive prevention and planning of cleanup efforts with relatively low costs regardless of the ocean litter's offshore or coastal origins and can provide support for regional-to-global actions and policies addressing the contemporary impacts of macro ocean litter on environments.
Nutrient subsidy of methane‐oxidising bacteria (MOB), an alternative basal resource, to plankton communities through pelagic‐benthic coupling is expected to alter carbon‐to‐nitrogen (C/N) ratios and ...biomass of zooplankton, and affect biological processes in aquatic food webs. Previous studies indicate that most MOB nutrient subsidies to zooplankton are focused largely on C subsidies; nevertheless, considering that N is important to zooplankton and phytoplankton growth, a better understanding of MOB N subsidies to plankton communities is needed.
We examined changes in nutrients, phytoplankton mass‐specific productivity, MOB reliance, C/N ratios and biomass of zooplankton between summer stratification and winter mixing periods based on in situ investigation in a subtropical deep oligotrophic freshwater ecosystem during 2010–2014.
The results revealed that with increasing reliance on MOB during the winter mixing period, zooplankton C/N ratios decreased and had a significantly nonlinearly inverse relationship with zooplankton biomass. The negative relationship between zooplankton biomass and phytoplankton mass‐specific productivity was further observed in synchronous time.
The profundal MOB enhanced pelagic‐profundal coupling and served as an alternative N support for pelagic plankton food webs during the winter and/or less productive seasons, adding to greater understanding of the role of methanotrophs in aquatic food webs.
Tropical cyclones (TCs), as natural extreme weather events, alter plankton and hydrological environments, affecting the stability of biological processes in freshwater ecosystems, and such TC effects ...vary with water depths. Previous studies have found increased phytoplankton biomass resulting from TC effects has been observed, leading to potential strong grazing of zooplankton and enhanced plankton trophic‐level relationships. However, this remains understudied, particularly under in situ conditions.
Using a zooplankton to phytoplankton (ZB/PB) ratio to represent the plankton trophic‐level relationship, we estimated the ZB/PB ratios at various depth intervals, including surface (2 m depth) and euphotic (depths between 0 and 20 m) depths and depth layer 0–50 m (depths between 0 and 50 m), in a subtropical deep oligotrophic freshwater ecosystem from 2012 to 2015 to understand how TC effects would influence changes in the ZB/PB ratio variations.
TCs affected the surface and euphotic ZB/PB ratios but not those at the depth layer 0–50 m. The TC durations had an initially negative and then positive impact on the surface ZB/PB ratio, indicating that slow‐moving TCs might restructure surface plankton trophic‐level relationships. The water temperature and nutrient dynamics during the TC weeks showed the highest correlations with the ZB/PB ratios at the surface and euphotic depths. The combined environmental effects influenced the ZB/PB ratios at the surface and euphotic depths during the TC weeks, with 65.1% and 72.2% of the total variations explained in the multivariate regressions, respectively.
There were greater impacts of TCs in shallow water (surface and euphotic depth) than in deep water. Aquatic food chains may be unexpectedly vulnerable to natural extreme weather events, such as TCs, and continuous assessments of food chain dynamics are necessary to better manage potential risks from natural extreme weather events in freshwater ecosystems.
Innate behaviors are genetically encoded, but their underlying molecular mechanisms remain largely unknown. Predator odor 2,4,5-trimethyl-3-thiazoline (TMT) and its potent analog ...2-methyl-2-thiazoline (2MT) are believed to activate specific odorant receptors to elicit innate fear/defensive behaviors in naive mice. Here, we conduct a large-scale recessive genetics screen of ethylnitrosourea (ENU)-mutagenized mice. We find that loss of Trpa1, a pungency/irritancy receptor, diminishes TMT/2MT and snake skin-evoked innate fear/defensive responses. Accordingly, Trpa1
mice fail to effectively activate known fear/stress brain centers upon 2MT exposure, despite their apparent ability to smell and learn to fear 2MT. Moreover, Trpa1 acts as a chemosensor for 2MT/TMT and Trpa1-expressing trigeminal ganglion neurons contribute critically to 2MT-evoked freezing. Our results indicate that Trpa1-mediated nociception plays a crucial role in predator odor-evoked innate fear/defensive behaviors. The work establishes the first forward genetics screen to uncover the molecular mechanism of innate fear, a basic emotion and evolutionarily conserved survival mechanism.
Rising ocean temperatures pose a continuing threat to marine fish communities. As warming has far‐reaching impacts at multiple ecological levels, incorporating multimodal data is necessary for more ...accurately forecasting the responses of species and communities to the warming ocean. Range shifts, life‐history changes, and alterations of trophic dynamics are three important aspects of warming impacts, yet there has not been a formal integration of all three aspects in the same analysis.
Here, we present a novel framework that integrates species distribution projections, life‐history changes, and food web dynamics to assess warming impacts on marine fish communities. We first introduce a simple yet effective way of incorporating thermal physiological data into the species distribution model without the need to empirically measure thermal performance curves. We then use the dynamic size‐spectrum model as the modeling backbone to incorporate data from species distributions and population‐level life history analyses. With this framework, we evaluate how individual species are affected under two warming scenarios (RCP4.5 and RCP8.5). We also simulate large‐scale top‐down and bottom‐up perturbations to examine community resilience under rising temperatures.
We find that warming generally reduces species biomass and shifts species size spectra towards larger individuals, even though the maximum size tends to decrease under warming. However, the exact responses to rising temperatures differ among species and do not exhibit strong correlations with species size and the pace of life history. More severe warming also renders the focal community more vulnerable to top‐down perturbations, even though the community remains sufficiently resilient overall.
The complex nature of species and community responses result from the fact that distribution range, life history, and food web dynamics change with warming in different directions that may not be intuitive to predict a priori. Importantly, we show that neglecting changes in species distribution or life history will lead to biased assessment of species and community responses. Our analyses highlight trophic dynamics, species biomass, and community resilience as three emergent properties that our framework can uniquely quantify. This integrative framework is readily applicable to other communities of interest and can be scaled up for multi‐regional or global analyses.
Yeast one-hybrid (Y1H) is a common technique for identifying DNA-protein interactions, and robotic platforms have been developed for high-throughput analyses to unravel the gene regulatory networks ...in many organisms. Use of these high-throughput techniques has led to the generation of increasingly large datasets, and several software packages have been developed to analyze such data. We previously established the currently most efficient Y1H system, meiosis-directed Y1H; however, the available software tools were not designed for processing the additional parameters suggested by meiosis-directed Y1H to avoid false positives and required programming skills for operation.
We developed a new tool named GateMultiplex with high computing performance using C++. GateMultiplex incorporated a graphical user interface (GUI), which allows the operation without any programming skills. Flexible parameter options were designed for multiple experimental purposes to enable the application of GateMultiplex even beyond Y1H platforms. We further demonstrated the data analysis from other three fields using GateMultiplex, the identification of lead compounds in preclinical cancer drug discovery, the crop line selection in precision agriculture, and the ocean pollution detection from deep-sea fishery.
The user-friendly GUI, fast C++ computing speed, flexible parameter setting, and applicability of GateMultiplex facilitate the feasibility of large-scale data analysis in life science fields.
Thiazoline-related innate fear-eliciting compounds (tFOs) orchestrate hypothermia, hypometabolism, and anti-hypoxia, which enable survival in lethal hypoxic conditions. Here, we show that most of ...these effects are severely attenuated in transient receptor potential ankyrin 1 (Trpa1) knockout mice. TFO-induced hypothermia involves the Trpa1-mediated trigeminal/vagal pathways and non-Trpa1 olfactory pathway. TFOs activate Trpa1-positive sensory pathways projecting from trigeminal and vagal ganglia to the spinal trigeminal nucleus (Sp5) and nucleus of the solitary tract (NTS), and their artificial activation induces hypothermia. TFO presentation activates the NTS-Parabrachial nucleus pathway to induce hypothermia and hypometabolism; this activation was suppressed in Trpa1 knockout mice. TRPA1 activation is insufficient to trigger tFO-mediated anti-hypoxic effects; Sp5/NTS activation is also necessary. Accordingly, we find a novel molecule that enables mice to survive in a lethal hypoxic condition ten times longer than known tFOs. Combinations of appropriate tFOs and TRPA1 command intrinsic physiological responses relevant to survival fate.
Ocean litter has accumulated rapidly and is becoming a major environmental concern, yet quantitative and regular observations and exploration that track litter origins are limited. By implementing ...monthly sample collections over five years (2012-2016) at Dongsha Island, a remote island in the northern South China Sea (SCS), we assessed macro ocean litter dynamics, identified source countries of individual plastic bottles, and analyzed the origins of the litter by a backward-tracking model simulation considering both the effects of current velocity and windage. The results showed that large amounts of litter, which varied monthly and annually in weight and quantity, reached the island during the study years, and there were spatial differences in accumulation patterns between the north and south coasts. Styrofoam and plastic bottles were the two primary sources of macro ocean litter both annually and monthly, and most of the litter collected on the island originated from China and Vietnam, which were collectively responsible for approximately 47.5%-63.7% per month. The simulation indicated that current advection at the near-surface depths and low windage at the sea surface showed similar patterns, while medium to high windage exhibited comparable expression patterns in response to potential source regions and drifting time experiments. At either the surface with low windage or current advection at depths of 0.5 m and 1 m, macro ocean litter in the Western Philippine Sea, i.e. through the Luzon Strait between Taiwan and the Philippines, was an important contributor to the litter bulk from October to March, whereas the litter was predicted to mainly originate from the southwestern SCS from April to September. With an increasing windage effect, litter in the Taiwan Strait was predicted to be an additional major potential source. Surprisingly, a small proportion of the macro ocean litter was predicted to continuously travel in the northern SCS for a long duration (> 2 years) before drifting onto Dongsha Island. The estimated drifting time of macro ocean litter also showed monthly and directional variability. This study demonstrated that a tremendous quantity of macro ocean litter, which may cause great damage to the marine ecosystem, drifts in the ocean surface layer and is finally pushed onto beaches. Therefore, we proposed an action plan for effective ocean litter management development at regional and global spatial scales, which is vital for improving and restoring the health and sustainability of the oceanic environment.
Small for gestational age (SGA) birth is associated with high rates of mortality and morbidity in preterm infants. The aim of this preliminary observational study was to investigate the difference in ...gut microbiota between SGA and appropriate for gestational age (AGA) preterm infants with very low birth weight (VLBW). We included 20 VLBW preterm infants (SGA,
= 10; AGA,
= 10) in this study. Stool samples were collected on days 7, 14, and 30 after birth. We performed 16S ribosomal DNA sequencing to compare microbiota composition between both groups. The SGA group exhibited a lower abundance of
on day 14 (SGA, 0.57%; AGA, 7.42%;
= 0.037). On day 30, the SGA group exhibited a lower abundance of
(SGA 3.76% vs. AGA 16.05%;
= 0.07) and
(SGA 5.09% vs. AGA 27.25%;
= 0.011) than the AGA group. Beta diversity demonstrated a separation of the bacterial community structure between both groups on day 30 (
= 0.019). The present study revealed that a distinct gut microbiota profile gradually develops in SGA preterm infants with VLBW during the early days of life. The role of changes in gut microbiota structure warrants further investigation.
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