Unraveling the CDK9/PP2A/ERK Network in Transcriptional Pause Release and Complement Activation in KRAS-mutant Cancers.

Selective inhibition of the transcription elongation factor (P-TEFb) complex represents a promising approach in cancer therapy, yet CDK9 inhibitors (CDK9i) are currently limited primarily to certain hematological malignancies. Herein, while initial responses to CDK9-targeted therapies are observed in vitro across various KRAS-mutant cancer types, their efficacy is far from satisfactory in nude mouse xenograft models. Mechanistically, CDK9 inhibition leads to compensatory activation of ERK-MYC signaling, accompanied by the recovery of proto-oncogenes, upregulation of immediate early genes (IEGs), stimulation of the complement C1r-C3-C3a cascade, and induction of tumor immunosuppression.

Monitoring of carbon-water fluxes at Eurasian meteorological stations using random forest and remote sensing.

Simulating the carbon-water fluxes at more widely distributed meteorological stations based on the sparsely and unevenly distributed eddy covariance flux stations is needed to accurately understand the carbon-water cycle of terrestrial ecosystems. We established a new framework consisting of machine learning, determination coefficient (R), Euclidean distance, and remote sensing (RS), to simulate the daily net ecosystem carbon dioxide exchange (NEE) and water flux (WF) of the Eurasian meteorological stations using a random forest model or/and RS. The daily NEE and WF datasets with RS-based information (NEE-RS and WF-RS) for 3774 and 4427 meteorological stations during 2002-2020 were produced, respectively.

Differential responses of CO and latent heat fluxes to climatic anomalies on two alpine grasslands on the northeastern Qinghai-Tibetan Plateau.

Discrete extreme heat events, deluges, and droughts will become more frequent and disproportionately affect the processes and functions of grassland ecosystems. Here, we compared the responses of CO and heat fluxes to natural extreme events in 2016 in a lower alpine meadow and neighboring upper shrubland on the northeastern Qinghai-Tibetan Plateau. Unlike insensitive sensible heat flux, latent heat flux (LE) increased by 21.

Interannual characteristics and driving mechanism of CO fluxes during the growing season in an alpine wetland ecosystem at the southern foot of the Qilian Mountains.

The carbon process of the alpine ecosystem is complex and sensitive in the face of continuous global warming. However, the long-term dynamics of carbon budget and its driving mechanism of alpine ecosystem remain unclear. Using the eddy covariance (EC) technique-a fast and direct method of measuring carbon dioxide (CO) fluxes, we analyzed the dynamics of CO fluxes and their driving mechanism in an alpine wetland in the northeastern Qinghai-Tibet Plateau (QTP) during the growing season (May-September) from 2004-2016.

Mapping Chinese annual gross primary productivity with eddy covariance measurements and machine learning.

Annual gross primary productivity (AGPP) is the basis for grain production and terrestrial carbon sequestration. Mapping regional AGPP from site measurements provides methodological support for analysing AGPP spatiotemporal variations thereby ensures regional food security and mitigates climate change. Based on 641 site-year eddy covariance measuring AGPP from China, we built an AGPP mapping scheme based on its formation and selected the optimal mapping way, which was conducted through analysing the predicting performances of divergent mapping tools, variable combinations, and mapping approaches in predicting observed AGPP variations.

Pixel-scale historical-baseline-based ecological quality: Measuring impacts from climate change and human activities from 2000 to 2018 in China.

Widespread concern about ecological degradation has prompted development of concepts and exploration of methods to quantify ecological quality with the aim of measuring ecosystem changes to contribute to future policy-making. This paper proposes a conceptual framework for ecological quality measurement based on current ecosystem functions and biodiverse habitat, compared with pixel-scale historical baselines. The framework was applied to evaluate the changes and driving factors of ecological quality for Chinese terrestrial ecosystems through remote sensing-based and ecosystem process modeled data at 1 km spatial resolution from 2000 to 2018.

Stability response of alpine meadow communities to temperature and precipitation changes on the Northern Tibetan Plateau.

Biomass temporal stability plays a key role in maintaining sustainable ecosystem functions and services of grasslands, and climate change has exerted a profound impact on plant biomass. However, it remains unclear how the community biomass stability in alpine meadows responds to changes in some climate factors (e.g.

Atmospheric water vapor and soil moisture jointly determine the spatiotemporal variations of CO fluxes and evapotranspiration across the Qinghai-Tibetan Plateau grasslands.

Alpine grasslands play important functions in mitigating climate change and regulating water resources. However, the spatiotemporal variability of their carbon and water budgets remains unquantified. Here, 47 site-year observations of CO and water vapor fluxes (ET) are analyzed at sites situated along a hydrothermal gradient across the Qinghai-Tibetan Plateau, including an alpine wetland (wettest), an alpine shrub (coldest), an alpine meadow, an alpine meadow-steppe, and an alpine steppe (driest and warmest).

Ambient climate determines the directional trend of community stability under warming and grazing.

Changes in ecological processes over time in ambient treatments are often larger than the responses to manipulative treatments in climate change experiments. However, the impacts of human-driven environmental changes on the stability of natural grasslands have been typically assessed by comparing differences between manipulative plots and reference plots. Little is known about whether or how ambient climate regulates the effects of manipulative treatments and their underlying mechanisms.

Warming homogenizes apparent temperature sensitivity of ecosystem respiration.

Warming-induced carbon loss through terrestrial ecosystem respiration () is likely getting stronger in high latitudes and cold regions because of the more rapid warming and higher temperature sensitivity of ( ). However, it is not known whether the spatial relationship between and temperature also holds temporally under a future warmer climate. Here, we analyzed apparent values derived from multiyear observations at 74 FLUXNET sites spanning diverse climates and biomes.

The paleoclimatic footprint in the soil carbon stock of the Tibetan permafrost region.

Tibetan permafrost largely formed during the late Pleistocene glacial period and shrank in the Holocene Thermal Maximum period. Quantifying the impacts of paleoclimatic extremes on soil carbon stock can shed light on the vulnerability of permafrost carbon in the future. Here, we synthesize data from 1114 sites across the Tibetan permafrost region to report that paleoclimate is more important than modern climate in shaping current permafrost carbon distribution, and its importance increases with soil depth, mainly through forming the soil's physiochemical properties.

Overall grazing tolerance index (overall GTI) is not an ideal predictor for describing a single-species tolerance to grazing.

Plants' pattern of compensatory growth is often used to intuitively estimate their grazing tolerance. However, this tolerance is sometimes measured by the overall grazing tolerance index (overall GTI), which assumes that tolerance is a multivariate linear function of various underlying mechanisms. Because the interaction among mechanisms is not independent, the grazing tolerance expression based on overall GTI may be inconsistent with that based on compensatory growth.

Effects of chemical substances on the rapid cultivation of moss crusts in a phytotron from the Loess Plateau, China.

In this study, typical moss crusts, which were dominated by the species Didymodon vinealis (Brid.) Zand., were collected from the Loess Plateau and a 65-day cultivation experiment was performed to study the effects of five kinds of nutrient solutions (Knop, Murashige-Skoog (MS), Benecke, Part and Hoagland), two kinds of carbohydrates (glucose and sucrose) and three kinds of plant growth regulators (thidiazuron (TDZ), 6-benzylaminopurine (6-BA) and naphthaleneacetic acid (NAA)) on the coverage, plant density, and plant height of moss crusts.

Spatiotemporal pattern of gross primary productivity and its covariation with climate in China over the last thirty years.

The uncertainties of China's gross primary productivity (GPP) estimates by global data-oriented products and ecosystem models justify a development of high-resolution data-oriented GPP dataset over China. We applied a machine learning algorithm developing a new GPP dataset for China with 0.1° spatial resolution and monthly temporal frequency based on eddy flux measurements from 40 sites in China and surrounding countries, most of which have not been explored in previous global GPP datasets.

Grassland restoration reduces water yield in the headstream region of Yangtze River.

Large-scale ecological restoration programs are considered as one of the key strategies to enhance ecosystem services. The Headstream region of Yangtze River (HYZR), which is claimed to be China's Water Tower but witnessed the rapid grassland deterioration during 1970s-2000, has seen a series of grassland restoration programs since 2000. But few studies have thoroughly estimated the hydrological effect of this recent grassland restoration.

Responses of sequential and hierarchical phenological events to warming and cooling in alpine meadows.

Organisms' life cycles consist of hierarchical stages, from a single phenological stage (for example, flowering within a season), to vegetative and reproductive phases, to the total lifespan of the individual. Yet phenological events are typically studied in isolation, limiting our understanding of life history responses to climate change. Here, we reciprocally transfer plant communities along an elevation gradient to investigate plastic changes in the duration of sequential phenological events for six alpine species.

Modeling net ecosystem carbon exchange of alpine grasslands with a satellite-driven model.

Estimate of net ecosystem carbon exchange (NEE) between the atmosphere and terrestrial ecosystems, the balance of gross primary productivity (GPP) and ecosystem respiration (Reco) has significant importance for studying the regional and global carbon cycles. Using models driven by satellite data and climatic data is a promising approach to estimate NEE at regional scales. For this purpose, we proposed a semi-empirical model to estimate NEE in this study.

Hysteresis responses of evapotranspiration to meteorological factors at a diel timescale: patterns and causes.

Evapotranspiration (ET) is an important component of the water cycle in terrestrial ecosystems. Understanding the ways in which ET changes with meteorological factors is central to a better understanding of ecological and hydrological processes. In this study, we used eddy covariance measurements of ET from a typical alpine shrubland meadow ecosystem in China to investigate the hysteresis response of ET to environmental variables including air temperature (Ta), vapor pressure deficit (VPD) and net radiation (Rn) at a diel timescale.

[Characteristics of evapotranspiration in an alpine shrub meadow in Haibei, Qinghai of Northwest China].

Evapotranspiration (ET) is an important component of hydrological cycle of terrestrial ecosystem. To study the seasonal and interannual ET variation patterns of typical ecosystems is essential to better understand the water cycle process and to provide reference for the rational utilization of water resources. By using eddy covariance method, this paper studied the seasonal and interannual variation characteristics of ET and water budget in an alpine shrub meadow ecosystem in Haibei of Qinghai from 2003 to 2011.

Gene or environment? Species-specific control of stomatal density and length.

Stomatal characteristics are used as proxies of paleo-environment. Only a few model species have been used to study the mechanisms of genetic and environmental effects on stomatal initiation. Variation among species has not been quantified.

Small-scale variation in ecosystem CO2 fluxes in an alpine meadow depends on plant biomass and species richness.

Characterizing the spatial variation in the CO2 flux at both large and small scales is essential for precise estimation of an ecosystem's CO2 sink strength. However, little is known about small-scale CO2 flux variations in an ecosystem. We explored these variations in a Kobresia meadow ecosystem on the Qinghai-Tibetan plateau in relation to spatial variability in species composition and biomass.