Fertilization of an egg by multiple sperm (polyspermy) leads to lethal genome imbalance and chromosome segregation defects. In
, the block to polyspermy is facilitated by a mechanism that prevents ...polytubey (the arrival of multiple pollen tubes to one ovule). We show here that FERONIA, ANJEA, and HERCULES RECEPTOR KINASE 1 receptor-like kinases located at the septum interact with pollen tube-specific RALF6, 7, 16, 36, and 37 peptide ligands to establish this polytubey block. The same combination of RALF (rapid alkalinization factor) peptides and receptor complexes controls pollen tube reception and rupture inside the targeted ovule. Pollen tube rupture releases the polytubey block at the septum, which allows the emergence of secondary pollen tubes upon fertilization failure. Thus, orchestrated steps in the fertilization process in
are coordinated by the same signaling components to guarantee and optimize reproductive success.
•MYB111 is a positive regulator in salt stress response.•MYB111 could bind to specific cis-elements in promoter of key enzyme genes of flavonoid synthesis.•MYB111’s role on salt resistance is ...dependent on its regulation on flavonoid synthesis.
Salt stress is an adverse environmental factor severely disturbing plant growth and development. Correspondingly, plants have evolved in a set of machinery to cope with salt toxicity including transcriptional regulation. In this study, by employing knockout and overproducing plants, we found that MYB111 is a positive regulator in salt stress response. MYB111 deficiency significantly decreased salt tolerance in Arabidopsis, whereas MYB111 overproduction dramatically increased during the stages of seed germination and seedling growth. Physiological analyses suggested that this altered sensitivity may be from different reactive oxygen species (ROS) scavenging capacity. ROS accumulation was higher in myb111 mutants than the wild-type (WT) plants, but lower in MYB111-overexpressed plants. Consistent to previous report that MYB111 is a regulator in flavonoid synthesis, flavonoid accumulation was lower in mutants, but higher in MYB111-overexpressed plants compared with WT. Surprisingly, addition of bioflavonoids, chalcone/ dihydrokaempferole/ quercetin were able to rescue the loss of salt tolerance in myb111 mutants, demonstrating that flavonoids are crucial against salt stress. Furthermore, we found that MYB111 can bind to specific cis-elements in promoter of chalcone synthase (CHS), flavanone carboxylase (F3H), flavonol synthase 1 (FLS1), and in turn activates their transcription. Meanwhile, MYB111 expression was highly induced under salt treatment, indicating its role in responses to salt stress. Taken together, our data clearly showed that MYB111’s role on salt resistance is dependent on its regulation on flavonoid synthesis.
Simultaneously tuning the electronic structure of active sites and the microenvironment of the carbon matrix in metal phosphide/carbon nanohybrids is the most effective way to design and develop ...bi-functional electrocatalysts for electrochemically related energy storage devices. Inspired by this, a robust and advanced N/P co-doped carbon-based dodecahedron catalyst with confined Fe-doped Co2P particles was successfully prepared through a multi-doping engineering strategy. Phytic acid molecules, which were used in the synthesis of the catalyst, not only contribute to the formation of the porous structure, but also act as a phosphorus source to form the corresponding metal phosphide and the P dopant in the carbon matrix. Thanks to the unique composition and structure-dependent merits, the microenvironment of the electrocatalyst was significantly modulated, thus promoting the advantageous local charge rearrangement and smooth mass/charge transfer processes during the oxygen-related electrocatalytic reactions. As a result, the resultant catalyst exhibited significantly enhanced reversible oxygen activity, as evidenced by an ultra-small potential gap of 0.655 V (half-wave potential of 0.895 V for the oxygen reduction reaction; η10 of 320 mV for the oxygen evolution reaction), a remarkable specific capacity of 762 mA h gZn−1, and high voltaic efficiency, exceeding most previous reports. This study provides a new synthetic approach for fabricating highly efficient bi-functional oxygen catalysts and can be handily extended to the synthesis of other heterogeneous electrocatalysts for sustainable energy storage.
: Tetraspanins constitute a family of transmembrane spanning proteins that function mainly by organizing the plasma membrane into micro-domains. CD82, a member of tetraspanins, is a potent inhibitor ...of cancer metastasis in numerous malignancies. CD82 is a highly glycosylated protein, however, it is still unknown whether and how this post-translational modification affects CD82 function and cancer metastasis.
: The glycosylation of CD82 profiles are checked in the paired human ovarian primary and metastatic cancer tissues. The functional studies on the various glycosylation sites of CD82 are performed in vitro and in vivo.
: We demonstrate that CD82 glycosylation at Asn157 is necessary for CD82-mediated inhibition of ovarian cancer cells migration and metastasis
and
. Mechanistically, we discover that CD82 glycosylation is pivotal to disrupt integrin α5β1-mediated cellular adhesion to the abundant extracellular matrix protein fibronectin. Thereby the glycosylated CD82 inhibits the integrin signaling pathway responsible for the induction of the cytoskeleton rearrangements required for cellular migration. Furthermore, we reveal that the glycosyltransferase MGAT3 is responsible for CD82 glycosylation in ovarian cancer cells. Metastatic ovarian cancers express reduced levels of MGAT3 which in turn may result in impaired CD82 glycosylation.
: Our work implicates a pathway for ovarian cancers metastasis regulation via MGAT3 mediated glycosylation of tetraspanin CD82 at asparagine 157.
Ground-based microwave radiometers (MWRs) operating in the K- and V-bands (20–60 GHz) can help us obtain temperature and humidity profiles in the troposphere. Aside from some soundings from local ...meteorological observatories, the tropospheric atmosphere over the Tibetan Plateau (TP) has never been continuously observed. As part of the Chinese Second Tibetan Plateau Scientific Expedition and Research Program (STEP), the Tibetan Plateau Atmospheric Profile (TP-PROFILE) project aims to construct a comprehensive MWR troposphere observation network to study the synoptic processes and environmental changes on the TP. This initiative has collected three years of data from the MWR network. This paper introduces the data information, the data quality, and data downloading. Some applications of the data obtained from these MWRs were also demonstrated. Our comparisons of MWR against the nearest radiosonde observation demonstrate that the TP-PROFILE MWR system is adequate for monitoring the thermal and moisture variability of the troposphere over the TP. The continuous temperature and moisture profiles derived from the MWR data provide a unique perspective on the evolution of the thermodynamic structure associated with the heating of the TP. The TP-PROFILE project reveals that the low-temporal resolution instruments are prone to large uncertainties in their vapor estimation in the mountain valleys on the TP.
Baicalin and berberine hydrochloride are the main chemical compositions of
and
respectively.
and
are two traditional Chinese herbs that are commonly used together in compounded formulations to treat ...colitis. Therefore, the combination of Baicalin and berberine hydrochloride (BBH) to treat colitis was studied. The results of pharmacological evaluations demonstrated the excellent protective effects of BBH on colitis induced by dextran sulfate sodium (DSS). BBH could improve the morphological condition of colitis in mice and maintain the balance of proinflammation cytokines (IL-6, IL-8, IL-1
, and TNF-
) and anti-inflammation cytokines (IL-4 and IL-10). The 16s rDNA sequencing revealed that BBH was able to modulate the composition of intestinal microflora, especially the abundances of
,
,
,
,
The results of PICRUSt indicated that the therapeutic effects of BBH were tightly connected with DNA synthesis, replication and repair of gut microbiota. In summary, it was concluded that BBH could protect mice against DSS-induced colitis, and the protective effects were tightly correlated with gut microbiota.
Objective
To investigate the effects of TNF‐α‐induced exosomes release on the biological behavior, metabolism, and bioenergetics of HUVECs.
Methods
Exosomes were isolated from conditioned media of ...HUVECs by ultracentrifugation after treatment with or without TNF‐α. HUVECs were treated with or without TNF‐α, or different concentrations of exosomes isolated from conditioned media with or without TNF‐α induction (TExo and CExo, respectively).
Results
The results showed that TNF‐α significantly inhibited migration, tube formation, and increased apoptosis rate of HUVECs compared with controls. Furthermore, TNF‐α‐induced exosomes (TExo) rather than CExo, indicated similar effects to inhibit migration, tube formation and promote endothelial apoptosis. Although TNF‐α treatment did not show a statistical difference, TExo significantly inhibited extracellular OCR compared with controls. TExo could significantly inhibited intracellular OCR in a hypoxia condition. TNF‐α significantly increased L‐ECA compared with control cells, and TExo showed similar stimulative effect on L‐ECA.
Conclusions
TNF‐α‐induced exosomes could significantly (a) change migration, tube formation, and apoptosis; (b) inhibit endothelial extracellular OCR and intracellular OCR (hypoxia); (c) increase glycolysis rate of the endothelial cells. These data provide new evidence for exploring endothelial behavior regulation using exosomes and their effects on endothelial metabolism and bioenergetics.
Abstract
Snowfall on the Tibetan Plateau (TP) is crucially important to the hydrological cycle and glacier acceleration over the TP and surroundings. Climate and weather models are challenged by ...biases and uncertainties in representing microphysical characteristics of snowfall over TP. In order to bridge the gaps in our understanding of microphysical characteristics of snowfall on the southeastern TP (SETP), an integrated and systematic measurement is conducted at the South‐East Tibetan Plateau Station during the two winters of 2022–2023. It is the first time to conduct a long‐term measurement of microphysical characteristics of snowfall on the SETP. The major objective of this campaign was to collect cloud microphysical properties including, fall velocity, aspect ratio, and particle size distribution (PSD). The results show that the particle number concentration is less than 10
3
mm
−1
·m
−3
, which is one to two orders of magnitude smaller than that reported in low‐altitudes in eastern China. The shape parameter
μ
is mainly in the range 0–4, and the slope parameter
λ
is mainly in the range 3–7 mm
−1
, exceeding the values for eastern China. In heavy snowfall processes (snowfall rate (SR) exceeding 2 mm/hr), the collision‐coalescence process between snowfall particles is enhanced, and the number concentration of small particles decreases with SR, whereas that of large particles increases. A negative correlation was observed between the aspect ratio and the diameter of snowfall particles. The microphysical characteristics of snowfall will be used to improve the microphysical scheme and evaluate the representation of precipitation in the climate model.
Plain Language Summary
Snowfall on the southeastern Tibetan Plateau (SETP) affects the mass change of glaciers, the energy balance, and precipitation patterns on the TP and their surrounding areas. However, a large part of the forecast bias for snowfall in climate and weather models comes from the representation of the microphysical characteristics of snowfall. In order to close the knowledge gap, we conducted a long‐term observation experiment of the microphysical characteristics of snowfall on the SETP for the first time. The research purpose of this experiment is to investigate the microphysical characteristics of snowfall on the southeastern TP, such as fall velocity, aspect ratio, particle size distribution, and its vertical variation. The results show that the particle size distribution of snowfall particles on the southeastern TP is lower than that in the low‐altitudes. With the increase of snowfall rate, the collision‐coalescence process between snowfall particles is enhanced, the number of small particles decreases, and the number of large particles increases. Observations of the microphysical characteristics of snowfall will help improve snowfall estimates in climate weather models.
Key Points
The first time to conduct a long‐term measurement of microphysical characteristics of snowfall on the southeastern Tibetan Plateau (SETP)
Comparing the particle number concentration of snowfall on the SETP with that in low‐altitudes areas
The microphysical processes that dominate snowfall under different snowfall rates are different
It is estimated that non-small-cell lung cancer (NSCLC) is responsible for 80% of human deaths related to lung cancer worldwide. Currently, it has been discovered that two transcription factors. ...Nuclear factor-κB (NF-κB) and Signal transducer and activator of transcription 3 (STAT3) were the main factors affecting inflammation and cancer, and their activation promoted lung cancer cell proliferation.
Hedyotis diffusa
Willd. (
H. diffusa
) is an herbal Chinese medicine, which has always been used for the treatment of malignant tumors in clinical. Previous research found that
H. diffusa
could inhibit the proliferation of H1975 cells, but the specific mechanisms remain elusive. We investigated the effects of total triterpenes extracted from
H. diffusa
(TTH) on the migration, proliferation and apoptosis of H1975 cells. Cell-cycle and immunofluorescence analysis showed that TTH could block H1975 cells at G0/G1 phase and induce apoptosis of experimental cells. The protein levels of Bcl-2 were decreased, while the levels of pro-apoptotic Bax were increased. In addition, TTH could also inhibit the migration of H1975 cells through downregulated MMP-2 and MMP-9 and upregulated TIMP-2. Further research found that the level of phospho-STAT3 was significantly decreased after administration of TTH. And protein expression level of NF-κB in nucleus was decreased after TTH treatment, while NF-κB in cytoplasm increased. These results suggested that TTH could inhibit the proliferation and migration of H1975 cells, and also could induce cell apoptosis. These effects were closely connected to the activation of NF-κB and the phosphorylation of STAT3.
Satellite-based precipitation retrievals such as the Integrated Multi-satellite Retrievals for Global Precipitation Measurement (IMERG), provide alternative data in mountainous regions. In this ...study, we evaluated IMERG in the Yarlung Tsangbo Grand Canyon (YGC) using ground observations. It was found that IMERG underestimated the total rainfall primarily due to under-detection of rainfall events, with misses being more prevalent than false alarms. We analyzed the relationships between the probability of detection (POD), false alarm ratio (FAR), bias in detection (BID), and Heidke skill score (HSS) and terrain factors. It was found that the POD decreased with elevation, leading to increased underestimation of rainfall events at higher elevations, and the FAR was higher in valley sites. In terms of the hit events, IMERG overestimated the light rainfall events and underestimated the heavy rainfall events and the negative bias in the hit events decreased with elevation. IMERG could capture the early morning peak precipitation in the YGC region but underestimated the amplitude of the diurnal variation. This bias was inherent at the sensor level, and the Global Precipitation Climatology Center (GPCC) calibration partially improved the underestimation. However, this improvement was not sufficient for the YGC region. This study fills the gap in IMERG validation in a complex mountainous region and has implications for users and developers.
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