Project description:Background: Responses to hypoxia have been investigated in many species; however, comparative study between conspecific geographical populations in different altitude regions is rare, especially for invertebrates . The migratory locust, Locusta migratoria, is widely distributed both on high-altitude Tibetan Plateau (TP) and on low-altitude North China Plain (NP). TP locusts have inhabited Tibetan Plateau since Quaternary glaciations events and thus probably have evolved superior capacity to deal with hypoxia. Results: Here we compared the hypoxic responses of TP and NP locusts from morphological, behavioral and physiological perspectives. We found that TP locusts were more tolerant of extreme hypoxia than NP locusts, with a lower proportion exhibiting stupor, a faster recovery time, and higher respiration rates. We compared the transcriptional profiles of field TP and NP locusts and found that their differences were possibly attributed to a combination of multiple factors, e.g. oxygen, UV radiation, temperature and nutrition. To evaluate why TP locusts respond to extreme hypoxia differently from NP locusts, we subjected them to extreme hypoxia and compared their transcriptional responses. We found that the aerobic metabolism was more active in TP locusts than in NP locusts. RNAi disruption of PDHE1b, an entry gene from glycolysis to TCA cycle, increased the ratio of stupor in Tibetan locusts and decreased the ATP content of Tibetan locusts in hypoxia, confirming the significant importance of this metabolic branch for TP locusts to conquer hypoxia. Conclusions: Here we show that TP locusts are better tolerant of hypoxia than NP locusts and the better capacity to modulate primary metabolism in TP locusts contributes to their superior tolerance of hypoxia compared to NP locusts.
Project description:BackgroundThe elevation and dissipation of pollutants after the ignition of fireworks in different functional areas of a valley city were investigated.MethodsThe Air Quality Index (AQI) as well as inter-day and intra-day concentrations of various air pollutants (PM10, PM2.5, SO2, NO2, CO, O3) were measured during two episodes that took place during Chinese New Year festivities.ResultsFor the special terrain of Jinan, the mean concentrations of pollutants increased sharply within 2-4 h of the firework displays, and concentrations were 4-6 times higher than the usual levels. It took 2-3 d for the pollutants to dissipate to background levels. Compared to Preliminary Eve (more fireworks are ignited on New Year's Eve, but the amounts of other human activities are also lesser), the primary pollutants PM2.5, PM10, and CO reached higher concentrations on New Year's Eve, and the highest concentrations of these pollutants were detected in living quarters. All areas suffered from serious pollution problems on New Year's Eve (rural = urban for PM10, but rural > urban for PM2.5). However, SO2 and NO2 levels were 20%-60% lower in living quarters and industrial areas compared to the levels in these same areas on Preliminary Eve. In contrast to the other pollutants, O3 concentrations fell instead of rising with the firework displays.ConclusionInteractions between firework displays and other human activities caused different change trends of pollutants. PM2.5 and PM10 were the main pollutants, and the rural living quarter had some of the highest pollution levels.
Project description:Background: Responses to hypoxia have been investigated in many species; however, comparative study between conspecific geographical populations in different altitude regions is rare, especially for invertebrates . The migratory locust, Locusta migratoria, is widely distributed both on high-altitude Tibetan Plateau (TP) and on low-altitude North China Plain (NP). TP locusts have inhabited Tibetan Plateau since Quaternary glaciations events and thus probably have evolved superior capacity to deal with hypoxia. Results: Here we compared the hypoxic responses of TP and NP locusts from morphological, behavioral and physiological perspectives. We found that TP locusts were more tolerant of extreme hypoxia than NP locusts, with a lower proportion exhibiting stupor, a faster recovery time, and higher respiration rates. We compared the transcriptional profiles of field TP and NP locusts and found that their differences were possibly attributed to a combination of multiple factors, e.g. oxygen, UV radiation, temperature and nutrition. To evaluate why TP locusts respond to extreme hypoxia differently from NP locusts, we subjected them to extreme hypoxia and compared their transcriptional responses. We found that the aerobic metabolism was more active in TP locusts than in NP locusts. RNAi disruption of PDHE1b, an entry gene from glycolysis to TCA cycle, increased the ratio of stupor in Tibetan locusts and decreased the ATP content of Tibetan locusts in hypoxia, confirming the significant importance of this metabolic branch for TP locusts to conquer hypoxia. Conclusions: Here we show that TP locusts are better tolerant of hypoxia than NP locusts and the better capacity to modulate primary metabolism in TP locusts contributes to their superior tolerance of hypoxia compared to NP locusts. FIELD POPULATION: TP locusts vs. NP locusts;direct comparison on 6 separate microarrays; each microarray compares one biological replicate; each biological replicate contains 10 individuals. LAB POPULATION: hypoxia-treated TP locusts vs TP locusts in normoxia; hypoxia-treated NP locusts vs NP locusts in normoxia; direct comparison on 6 separate microarrays; each microarray compares one biological replicate; each biological replicate contains 10 individuals.
Project description:The Tibetan Plateau uplift and Cenozoic global cooling are thought to induce enhanced aridification in the Asian interior. Although the onset of Asian desertification is proposed to have started in the earliest Miocene, prevailing desert environment in the Tarim Basin, currently providing much of the Asian eolian dust sources, is only a geologically recent phenomenon. Here we report episodic occurrences of lacustrine environments during the Late Miocene and investigate how the episodic lakes vanished in the basin. Our oxygen isotopic (δ(18)O) record demonstrates that before the prevailing desert environment, episodic changes frequently alternating between lacustrine and fluvial-eolian environments can be linked to orbital variations. Wetter lacustrine phases generally corresponded to periods of high eccentricity and possibly high obliquity, and vice versa, suggesting a temperature control on the regional moisture level on orbital timescales. Boron isotopic (δ(11)B) and δ(18)O records, together with other geochemical indicators, consistently show that the episodic lakes finally dried up at ∼4.9 million years ago (Ma), permanently and irreversibly. Although the episodic occurrences of lakes appear to be linked to orbitally induced global climatic changes, the plateau (Tibetan, Pamir, and Tianshan) uplift was primarily responsible for the final vanishing of the episodic lakes in the Tarim Basin, occurring at a relatively warm, stable climate period.
Project description:El Niño-Southern Oscillation (ENSO) teleconnections are an important predictability source for extratropical seasonal climate forecasts. Previous studies suggest that the ENSO teleconnection pattern depends on the ENSO phase (El Niño vs. La Niña) and/or Sea Surface Temperature (SST) pattern (central Pacific vs. eastern Pacific El Niño events). Observations and ensemble simulations with the CNRM-CM6.1 atmospheric general circulation model indicate that only extreme El Niño events (e.g. 1982-1983, 1997-1998, 2015-2016) display a statistically significant eastward shift relative to the well-known Pacific-North American teleconnection pattern that occurs during both central and eastern Pacific moderate El Niño or during La Niña. This specific teleconnection pattern emerges when equatorial SST anomalies are both eastward-shifted and sufficiently large to exceed the deep atmospheric convection threshold over most of the eastern Pacific, resulting in a basin-wide reorganization of tropospheric heat sources. It yields> 0.5 std wet conditions over Western United States (74% likelihood) as well as> 0.5 std warm anomalies over Canada and the Northern United States (71% likelihood), with more consistency across events and ensemble members than for any other El Niño or La Niña type. These findings hold important implications for the seasonal forecasting of El Niño's impacts on the North American climate.
Project description:Posttranslational modifications such as phosphorylation are universally acknowledged regulators of protein function. Recently we characterised a striated muscle-specific isoform of the formin FHOD3 that displays distinct subcellular targeting and protein half-life compared to its non-muscle counterpart and which is dependent on phosphorylation by CK2 (formerly casein kinase 2). We now show that the two isoforms of FHOD3 are already expressed in the vertebrate embryonic heart. Analysis of CK2 alpha knockout mice showed that phosphorylation by CK2 is also required for proper targeting of muscle FHOD3 to the myofibrils in embryonic cardiomyocytes in situ. The localisation of muscle FHOD3 in the sarcomere varies depending on the maturation state, being either broader or restricted to the Z-disc proper in the adult heart. Following myofibril disassembly, such as that in dedifferentiating adult rat cardiomyocytes in culture, the expression of non-muscle FHOD3 is up-regulated, which is reversed once the myofibrils are reassembled. The shift in expression levels of different isoforms is accompanied by an increased co-localisation with p62, which is involved in autophagy, and affects the half-life of FHOD3. Phosphorylation of three amino acids in the C-terminus of FHOD3 by ROCK1 is sufficient for activation, which results in increased actin filament synthesis in cardiomyocytes and also a broader localisation pattern of FHOD3 in the myofibrils. ROCK1 can directly phosphorylate FHOD3, and FHOD3 seems to be the downstream mediator of the exaggerated actin filament formation phenotype that is induced in cardiomyocytes upon the overexpression of constitutively active ROCK1. We conclude that the expression of the muscle FHOD3 isoform is characteristic of the healthy mature heart and that two distinct phosphorylation events are crucial to regulate the activity of this isoform in thin filament assembly and maintenance.
Project description:A series of trace compounds (diamondoids, ethanodiamondoids, and thiadiamondoids) were detected through two-dimensional gas chromatography/time-of-flight mass spectrometry (GC × GC-TOFMS) analysis of Ordovician condensate samples from the Tazhong area. Gas chromatography-mass spectrometry (GC-MS) analysis showed that the biomarker parameters are less effective for high-maturity oils. Carbon isotope and geochemical features suggested that the gas is a high-temperature cracking gas when its temperature is higher than 170 °C. The H2S content is 8.27%, suggesting that it is affected by thermochemical sulfate reduction (TSR). However, the geological analysis indicated that the Ordovician reservoirs do not satisfy the conditions for TSR. The high-maturity oil in the Ordovician reservoirs may generate diamondoids and ethanodiamondoids when cracking, while TSR and severe cracking occur in deep Cambrian source rocks and produce a large number of diamondoids, ethanodiamondoids, organic sulfur compounds (OSCs), etc. The secondary geochemical products that are carried up by the dry gas and migrate upward through faults and are enriched in Ordovician crude oil reservoirs. On this basis, we proposed that the condensate presented was formed by the mixing of dry gas from Cambrian oil that was altered by cracking and TSR into Ordovician in situ slightly cracked oil, therefore speculating that the favorable reservoir-seal assemblages in this area may contain abundant oil and gas resources. Consequently, improved knowledge of secondary alteration effects on the reservoir and underground fluids is vital for oil and gas prediction and exploration development in the next step.
Project description:It is well established that the expression profiles of multiple and possibly redundant matrix-remodeling proteases (e.g., collagenases) differ strongly in health, disease, and development. Although enzymatic redundancy might be inferred from their close similarity in structure, their in vivo activity can lead to extremely diverse tissue-remodeling outcomes. We observed that proteolysis of collagen-rich natural extracellular matrix (ECM), performed uniquely by individual homologous proteases, leads to distinct events that eventually affect overall ECM morphology, viscoelastic properties, and molecular composition. We revealed striking differences in the motility and signaling patterns, morphology, and gene-expression profiles of cells interacting with natural collagen-rich ECM degraded by different collagenases. Thus, in contrast to previous notions, matrix-remodeling systems are not redundant and give rise to precise ECM-cell crosstalk. Because ECM proteolysis is an abundant biochemical process that is critical for tissue homoeostasis, these results improve our fundamental understanding its complexity and its impact on cell behavior.
Project description:Increasing evidence suggests that Parkinson's disease (PD) exhibits disparate spatial and temporal patterns of progression. Here we used a machine-learning technique-Subtype and Stage Inference (SuStaIn) - to uncover PD subtypes with distinct trajectories of clinical and neurodegeneration events. We enrolled 228 PD patients and 119 healthy controls with comprehensive assessments of olfactory, autonomic, cognitive, sleep, and emotional function. The integrity of substantia nigra (SN), locus coeruleus (LC), amygdala, hippocampus, entorhinal cortex, and basal forebrain were assessed using diffusion and neuromelanin-sensitive MRI. SuStaIn model with above clinical and neuroimaging variables as input was conducted to identify PD subtypes. An independent dataset consisting of 153 PD patients and 67 healthy controls was utilized to validate our findings. We identified two distinct PD subtypes: subtype 1 with rapid eye movement sleep behavior disorder (RBD), autonomic dysfunction, and degeneration of the SN and LC as early manifestations, and cognitive impairment and limbic degeneration as advanced manifestations, while subtype 2 with hyposmia, cognitive impairment, and limbic degeneration as early manifestations, followed later by RBD and degeneration of the LC in advanced disease. Similar subtypes were shown in the validation dataset. Moreover, we found that subtype 1 had weaker levodopa response, more GBA mutations, and poorer prognosis than subtype 2. These findings provide new insights into the underlying disease biology and might be useful for personalized treatment for patients based on their subtype.