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The hallmark of coronavirus infection lies in its ability to evade host immune defenses, a process intricately linked to the nuclear entry of transcription factors crucial for initiating the expression of antiviral genes. Central to this evasion strategy is the manipulation of the nucleocytoplasmic trafficking system, which serves as an effective target for the virus to modulate the expression of immune response-related genes. In this investigation, we discovered that infection with the infectious bronchitis virus (IBV) dynamically impedes the nuclear translocation of several transcription factors such as IRF3, STAT1, STAT2, NF-κB p65, and the p38 MAPK, leading to compromised transcriptional induction of key antiviral genes such as IFNβ, IFITM3, and IL-8. Further examination revealed that during the infection process, components of the nuclear pore complex (NPC), particularly FG-Nups (such as NUP62, NUP153, NUP42, and TPR), undergo cytosolic dispersion from the nuclear envelope; NUP62 undergoes phosphorylation, and NUP42 exhibits a mobility shift in size. These observations suggest a disruption in nucleocytoplasmic trafficking. Screening efforts identified the IBV nucleocapsid (N) protein as the agent responsible for the cytoplasmic distribution of FG-Nups, subsequently hindering the nuclear entry of transcription factors and suppressing the expression of antiviral genes. Interactome analysis further revealed that the IBV N protein interacts with the scaffold protein RACK1, facilitating the recruitment of activated protein kinase C alpha (p-PKCα) to RACK1 and relocating the p-PKCα-RACK1 complex to the cytoplasm. These observations are conserved across diverse coronaviruses N proteins. Concurrently, the presence of both RACK1 and PKCα/β proved essential for the phosphorylation and cytoplasmic dispersion of NUP62, the suppression of antiviral cytokine expression, and efficient virus replication. These findings unveil a novel, highly effective, and evolutionarily conserved mechanism. Author summary: Coronaviruses employ diverse strategies to suppress the host innate immune defense. In this study, we uncovered a novel and highly effective strategy utilized by diverse coronaviruses to inhibit the innate immune response. Specifically, we found that the coronavirus N protein facilitates the binding of p-PKCα to RACK1, leading to the phosphorylation of NUP62 and the cytoplasmic redistribution of multiple FG-Nups. This phenomenon is accompanied by the disruption of nuclear translocation of several innate immune response-related transcription factors and suppression of antiviral/pro-inflammatory gene expression. Our research represents the first elucidation of how the N protein targets and impairs NPC function through the promotion of p-PKCα- RACK1 interaction and NUP62 phosphorylation/disassembly. This discovery unveils a novel mechanism employed by diverse coronaviruses to counteract the host immune response. [ABSTRACT FROM AUTHOR]

【Objective】 Evaporation loss via capillary rise is an important component of groundwater cycle but difficult to measure in situ. This paper presents an empirical formula to estimate it using surface evaporation and ambient air temperature, based on long-term experimental data obtained from a hydrological experimental station. 【Method】 Groundwater evaporation from phreatic surface of shallow groundwater was measured from lysimeters with cross section of 0.3 m2 at Wudaogou Hydrological Experiment Station, and the meteorological data were measured from a weather station installed at the station. There were two soils, a fluvo-aquic soil and a lime concretion black soil. For each soil, we established a regression model using temperature and surface evaporation, either separately or in combination, to estimate groundwater evaporation. 【Result】 For the lime concretion black soil, the average R2 of the models using single or two meteorological factors was 0.88, and its associated average absolute error (MAE) and root mean square error (RMSE) were 0.15 mm/d and 0.23 mm/d, respectively. For the yellow fluvo-aquic soil, the associated results were R2=0.92, MAE=0.194 mm, and RMSE=0.28 mm/d. When using a single meteorological factor, the average R2 for the two soils using all models was R2=0.92, and its associated MAE and RMSE were 0.18 mm/d and 0.26 mm/d, respectively. In contrast, in using the two meteorological factors, the average R2 for the two soils using all models was 0.94, and its associated MAE and RMSE were 0.14 mm/d and 0.205 mm/d, respectively. 【Conclusion】 For a given area, the evaporation of its shallow groundwater via capillary rise depends on surface evaporation and ambient air temperature. Since air temperature and surface evaporation are closely correlated, we can use either one of the two factor or their combination to estimate the groundwater evaporation.