SCP1 as a nuclear transcriptional regulator acts globally to silence neuronal genes and to affect the dephosphorylation of RNA Pol ll. However, we report the first finding and description of SCP1 as a plasma membrane-localized protein in various cancer cells using EGFP- or other epitope-fused SCP1. Membrane-located SCP1 dephosphorylates AKT at serine 473, leading to the abolishment of serine 473 phosphorylation that results in suppressed angiogenesis and a decreased risk of tumorigenesis. Consistently, we observed increased AKT phosphorylation and angiogenesis followed by enhanced tumorigenesis in Ctdsp1 (which encodes SCP1) gene - knockout mice. Importantly, we discovered that the membrane localization of SCP1 is crucial for impeding angiogenesis and tumor growth, and this localization depends on palmitoylation of a conserved cysteine motif within its NH2 terminus. Thus, our study discovers a novel mechanism underlying SCP1 shuttling between the plasma membrane and nucleus, which constitutes a unique pathway in transducing AKT signaling that is closely linked to angiogenesis and tumorigenesis.DOI: http://dx.doi.org/10.7554/eLife.22058.001

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Rivers and streams contribute significant quantities of methane (CH4) to the atmosphere. However, there is a lack of CH4 flux and ebullitive (bubble) emission data from urban rivers, which might lead to large underestimations of global aquatic CH4 emissions. Here, we conducted high-frequency surveys using the boundary layer model (BLM) supplemented with floating chambers (FCs) and bubble traps to investigate the seasonal and diurnal variability in CH4 emissions in a eutrophic urban river and to evaluate whether the contribution of bubbles is important. We found that ebullition contributed nearly 99% of CH4 emissions and varied on hourly to seasonal time scales, ranging from 0.83 to 230 mmol m–2 d–1, although diffusive emissions and CH4 concentrations in bubbles did not exhibit temporal variability. Ebullitive CH4 emissions presented high temperature sensitivity (r = 0.6 and p < 0.01) in this urban river, and eutrophication might have triggered this high temperature sensitivity. The ebullitive CH4 flux is more likely to be underestimated at low temperatures because capturing the bubble flux is more difficult, given the low frequency of ebullition events. This study suggests that future ebullition measurements on longer time scales are needed to accurately quantify the CH4 budgets of eutrophic urban rivers.

To investigate the role of macrophages in the osseointegration of dental implants through induced macrophage reduction in a murine model. Fifty‐four Sprague–Dawley rats with bilateral maxillary first molars replaced by titanium implants were randomly assigned into three groups. For the test group, macrophages were depleted by tail‐vein injection of clodronate liposome (20 mg/kg) 3 days before implantation and reinjection every 3 days until the sacrifice of the rats (10 mg/kg). Animals treated with Phosphate Buffer saline (PBS) alone or empty liposome were included as controls. Samples contained implants were retrieved after 3, 7, 14, and 28 days, and the alterations of macrophages (CD68) and osteoblasts (Osterix) were evaluated using histology and immunohistochemistry technique. Histological analysis showed that new bone gradually formed within the lateral chamber regions in both the Control group and the Lip group, whereas bone healing was delayed at the first 2‐weeks despite of pronounced newly formed peri‐implant bone at 4 weeks in the Lipclod group. The bone‐to‐implant contact was significantly higher in the Lip and Control group than in the Lipclod group after 2 weeks. Immunohistochemical analysis showed that CD68+ cells were present both in the central region and in direct contact with implant surface throughout the healing period. Macrophages depletion reduced osteoblast amounts and new bone formation around implants in the first 2 weeks, and have no adverse impacts on the final formation of osseointegration. Macrophages play a dual role in both regulating the bone healing process and immune response to implant installation during the early stages.

Core Ideas We investigated estuarine environmental factors on CH4 flux from two vegetation communities. Warming significantly affected on CH4 emission from the Phragmites australis community. There was a significant correlation between CH4 flux and water level in both communities. Salinity significantly affects CH4 emissions from the Phragmites australis community. The interaction between temperature and water level was the most important factor controlling CH4 flux. Global warming, rising sea levels, and saltwater intrusion interact to affect carbon cycling, specifically methane (CH4) flux in estuarine coastal wetlands. In the present study, Phragmites australis and Spartina alterniflora communities in the intertidal zone of the Yangtze estuary were selected for investigating CH4 flux under different temperature (natural/warming), water level (high/low), and salinity (0, 5, 15, and 30‰) conditions. The average CH4 flux (from April to October 2016) under natural conditions was 141.0 ± 21.5 and 502.8 ± 65.3 μmol m−2 h−1 for P. australis and S. alterniflora communities, respectively. Warming had a particularly pronounced effect on CH4 emissions from the P. australis community and increased CH4 flux by 130%. There was a significant correlation between CH4 flux and water level; at high water levels, CH4 flux was 2.64‐ and 3.78‐fold higher in P. australis and S. alterniflora communities, respectively. Salinity had a significant pronounced effect on CH4 emissions from the P. australis community, and there was a clear order (5‰ > 15‰ > 0‰ > 30‰) in CH4 flux. The interaction between temperature and water level was the most important factor controlling CH4 flux from wetlands; CH4 emissions were greater at higher temperature and higher water levels. However, at low water level, the effect of salinity was more prominent. The results suggest that CH4 flux from estuarine wetlands could be further enhanced in the future under the influence of rising sea levels due to global warming.