Physical Properties of Radio Stars Based on LAMOST Spectral Survey

Radio emission has been detected for all types of stars in the Hertzsprung Russell diagram. Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) low and medium-resolution spectroscopic surveys provide a good opportunity to obtain the spectroscopic properties of radio stars. We cross-matched big data from the LAMOST DR7 low resolution spectral survey with a catalogue of radio stars, and obtained 449 stellar spectra of 258 stars. We detected 185 spectra with Hα role= presentation style= box-sizing: border-box; max-height: none; display: inline; line-height: normal; font-size: 13.2px; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; color: rgb(34, 34, 34); font-family: Arial, Arial, Helvetica, sans-serif; position: relative; \u3eα emission. There are a total of 108 objects with repeated low resolution spectral observations, of which 63 show variations in the Hα role= presentation style= box-sizing: border-box; max-height: none; display: inline; line-height: normal; font-size: 13.2px; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; color: rgb(34, 34, 34); font-family: Arial, Arial, Helvetica, sans-serif; position: relative; \u3eα line over a long time, about several months. We cross-matched LAMOST DR7 medium resolution spectra with the radio star catalogue. We obtained 1319 LAMOST medium-resolution spectra of the 156 radio stars and then calculated their equivalent widths (EWs role= presentation style= box-sizing: border-box; max-height: none; display: inline; line-height: normal; font-size: 13.2px; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; color: rgb(34, 34, 34); font-family: Arial, Arial, Helvetica, sans-serif; position: relative; \u3eEWs) of the Hα role= presentation style= box-sizing: border-box; max-height: none; display: inline; line-height: normal; font-size: 13.2px; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; color: rgb(34, 34, 34); font-family: Arial, Arial, Helvetica, sans-serif; position: relative; \u3eα line. Among them, 93 radio stars with Hα role= presentation style= box-sizing: border-box; max-height: none; display: inline; line-height: normal; font-size: 13.2px; overflow-wrap: normal; white-space: nowrap; float: none; direction: ltr; max-width: none; min-width: 0px; min-height: 0px; border: 0px; padding: 0px; margin: 0px; color: rgb(34, 34, 34); font-family: Arial, Arial, Helvetica, sans-serif; position: relative; \u3eα emission were found from the LAMOST medium resolution spectra, and 63 objects showed short and long-term variabilities, especially on a short time scale of approximately 20 min. Finally, we estimated the minimal detectable radio flux of the FAST telescope and provided a scientific plan for studying radio stars

Statistical and Radio Analysis of Exoplanets and Their Host Stars

As of February 2022, over 4900 exoplanets have been confirmed. In this study, we conducted statistical analyses on both the exoplanets and their host stars’ parameters. Our findings suggest that the radius and true mass distribution of the exoplanets remain largely unchanged compared to prior research. However, we observed a correlation between the average eccentricity and the number of planets in a system, and fluctuations in the “size” of the planets may contribute to such variation. Moreover, we discovered that, among planets with precise measurements of radius, true mass, and semi-major axis, the true mass-radius relationship follows a power–law distribution. Interestingly, the power–law index tends to decrease from super-Earths to cold Jupiters, potentially due to atmospheric composition. We also revised the radius valley, and determined that M-type host stars with low mass and metal abundance exhibit high planetary ownership rates or harbor large-mass planets, suggesting a different planet formation mechanism than GK-type stars. Lastly, we assessed the possibility of detecting exoplanets using FAST and found that there are three planets in FAST sky that may be detected, namely CoRoT-3 b, GPX-1 b, and TOI-2109 b

MAP4K4 associates with BIK1 to regulate plant innate immunity

King Abdullah University of Science and Technology (KAUST). Grant Numbers: BAS/1/1062‐01‐01, URF/1/2965‐01‐01 Institut National de la Recherche Agronomique (INRA). Grant Number: ANR‐10‐LABX‐0040‐SPS Centre National de la Recherche Scientifique (CNRS). Grant Number: ANR‐10‐LABX‐0040‐SPS LabEx Saclay Plant Sciences‐SPSTo perceive pathogens, plants employ pattern recognition receptor (PRR) complexes, which then transmit these signals via the receptor-like cytoplasmic kinase BIK1 to induce defense responses. How BIK1 activity and stability are controlled is still not completely understood. Here, we show that the Hippo/STE20 homolog MAP4K4 regulates BIK1-mediated immune responses. MAP4K4 associates and phosphorylates BIK1 at Ser233, Ser236, and Thr242 to ensure BIK1 stability and activity. Furthermore, MAP4K4 phosphorylates PP2C38 at Ser77 to enable flg22-induced BIK1 activation. Our results uncover that a Hippo/STE20 homolog, MAP4K4, maintains the homeostasis of the central immune component BIK1

Physical Properties of Three Eclipsing Binaries of V Crt, WY Cnc and CG Cyg with Radio Radiation

Radio radiation has been detected across the Hertzsprung Russell diagram. We selected three objects with radio radiation (a semi-detached eclipsing binary V Crt, and two detached binaries WY Cnc and CG Cyg) that show magnetic activity. We made new photometric observations using a SARA 60 cm and NAOC 85 cm optical telescopes. Then, we obtained their orbital and starspot parameters by analyzing our light curves and published radial velocities using the updated Wilson-Devinney program. We revised the ephemeris information for V Crt and WY Cnc by analyzing the orbital minimum times. The orbital periods increased by 2.8 (±2.1) ×10−9 d yr−1 for V Crt, which maybe caused by mass transfer. The orbital periods decreased by −8.641 (±0.004) ×10−8 d yr−1 for WY Cnc. Orbital period change for CG Cyg was also found and we used a third-body of M3 of 0.14 M⊙ and a period of approximately 59.20 (0.36) yr to explain that. We also analysed the possible second period oscillation of CG Cyg with a cycle about 18.31 (0.06) yr. The long period changes of WY Cnc and CG Cyg might be caused by magnetic activity or stellar wind, rather than mass transfer

CATION-CHLORIDE CO-TRANSPORTER 1 (CCC1) Mediates Plant Resistance against Pseudomonas syringae

International audiencePlasma membrane (PM) depolarization functions as an initial step in plant defense signaling pathways. However, only a few ion channels/transporters have been characterized in the context of plant immunity. Here, we show that the Arabidopsis (Arabidopsis thaliana) Na+:K+:2Cl(-) (NKCC) cotransporter CCC1 has a dual function in plant immunity. CCC1 functions independently of PM depolarization and negatively regulates pathogen-associated molecular pattern-triggered immunity. However, CCC1 positively regulates plant basal and effector-triggered resistance to Pseudomonas syringae pv. tomato (Pst) DC3000. In line with the compromised immunity to Pst DC3000, ccc1 mutants show reduced expression of genes encoding enzymes involved in the biosynthesis of antimicrobial peptides, camalexin, and 4-OH-ICN, as well as pathogenesis-related proteins. Moreover, genes involved in cell wall and cuticle biosynthesis are constitutively down-regulated in ccc1 mutants, and the cell walls of these mutants exhibit major changes in monosaccharide composition. The role of CCC1 ion transporter activity in the regulation of plant immunity is corroborated by experiments using the specific NKCC inhibitor bumetanide. These results reveal a function for ion transporters in immunity-related cell wall fortification and antimicrobial biosynthesis

Molecular insights into the Darwin paradox of coral reefs from the sea anemone Aiptasia

Symbiotic cnidarians such as corals and anemones form highly productive and biodiverse coral reef ecosystems in nutrient-poor ocean environments, a phenomenon known as Darwin’s paradox. Resolving this paradox requires elucidating the molecular bases of efficient nutrient distribution and recycling in the cnidarian-dinoflagellate symbiosis. Using the sea anemone Aiptasia, we show that during symbiosis, the increased availability of glucose and the presence of the algae jointly induce the coordinated up-regulation and relocalization of glucose and ammonium transporters. These molecular responses are critical to support symbiont functioning and organism-wide nitrogen assimilation through glutamine synthetase/glutamate synthase–mediated amino acid biosynthesis. Our results reveal crucial aspects of the molecular mechanisms underlying nitrogen conservation and recycling in these organisms that allow them to thrive in the nitrogen-poor ocean environments.publishe

Transcriptomic Characterization of Hepatocellular Carcinoma with <i>CTNNB1</i> Mutation

<div><p>Purpose</p><p>Hepatocellular carcinoma (HCC) is the sixth most common solid tumor worldwide and the third leading cause of cancer-related death. HCC is a particularly serious threat to the Chinese population. Although many molecular alterations are known to be involved in the tumorigenesis of hepatocytes, no systemic survey has examined the somatic mutations in HCC samples from Chinese patients. Our goal was to elucidate somatic mutations in Chinese HCC patients and investigate the possible molecular mechanisms involved in tumorigenesis.</p><p>Experimental Design</p><p>A total of 110 hepatitis B virus (HBV)-positive HCC samples and 46 HBV-negative HCC samples were genotyped for hot-spot mutations in the <i>CSF1R</i>, <i>CTNNB1</i>, <i>KRAS</i>, <i>BRAF</i>, <i>NRAS</i>, <i>ERBB2</i>, <i>MET</i>, <i>PIK3CA</i>, <i>JAK1</i>, and <i>SMO</i> genes. The transcriptomes of the <i><u>C</u>TNNB1</i> mutation-positive HCC samples from the H<u>B</u>V-positive patients (CB+ HCC) were compared to adjacent non-cancerous livers, and significantly altered genes were functionally validated <i>in vitro</i>.</p><p>Results</p><p><i>CTNNB1</i> mutations accounted for the majority of the mutations detected in our study. A slightly higher mutation rate was found in the HBV-positive patients than in their negative counterparts. A distinct pattern of <i>CTNNB1</i> mutation was detected in these two populations, and drastic changes at the transcriptomic level were detected in the CB+ tumors compared to adjacent non-cancerous livers. Potential tumor suppressors (FoxA3 and Onecut1) and oncogenes (MAFG and SSX1) were functionally validated.</p><p>Conclusions</p><p>Our work is the first systemic characterization of oncogenic mutations in HCC samples from Chinese patients. Targeting the Wnt-β-catenin pathway may represent a valid treatment option for Chinese HCC patients. Our work also suggests that targeting ONECUT1, FOXA3, SSX1, and MAFG may be a valid treatment option for CTNNB1 mutation positive HCC patients.</p></div

<i>CTNNB1</i> mutation-positive patients have a better prognosis.

<p>Statistical analysis of 110 HBV-positive patients and 46 HBV-negative HCC patients showed that the <i>CTNNB1</i> mutation-positive patients have a longer survival time; Difference was not significant.</p

Statistical analysis of mutational information in the Chinese HCC patients.

<p>A: <i>CTNNB1</i> mutation is the predominant mutagenic event. Of the 156 samples assessed, 15 cases (9.6%) were found to have <i>CTNNB1</i> mutations. 14 cases (8.97%) had CTNNB1 mutation only, one case (0.64%) harbored CTNNB1 mutation and SMO (K575M) mutation, and one case (0.64%) had a KRAS (G12D) mutation. B: All of the mutations in CTNNB1 were clustered within the N-terminal region; five cases exhibited the T41A mutation, whereas three cases had the S37C mutation. The G34E and S45P mutations were found in two cases each, and the G34V, D32Y and D32G mutations were detected in only one case each in this study.</p

Potential tumor suppressors and oncogenes are involved in tumorigenesis.

<p>A: MAFG and SSX1 synergize mutant β-catenin on transcriptional activity. 293T cells transfected with vehicle (VEH), expression vector for FLAG tagged SSX1, or FLAG tagged MAFG with/without mutant β-catenin. (−) for without and (+) for with mutant β-catenin using Dual-Luciferase Reporter Assay System. Fold-change of luciferase activity is grafted. B: Representative Western blot analysis was conducted with anti-FLAG antibody on cells transfected with β-catenin and VEH, SSX1, or MAFG. C: Onecut1 and FoxA3 overexpression inhibits the growth of HCC cancer cells. D: Representative Western blot analysis was conducted with anti-FLAG antibody on HepG2 and Hep3B cells transfected with FLAG tagged GFP, ONECUT1 and FOXA3.*P value 0.05-0.01; **P value <0.01</p