Nonlabens dokdonensis视紫红质2中的钠离子结合与pH依赖性的传递（英文）

正Dear editor,Light-driven Na~+ pumping rhodopsins(Na Rs),the next generation optogenetic tools,are a family of seven-helical transmembrane proteins and covalently link to a retinal chromophore~([1]).Na Rs have a putative Na~+ -conducting motif of Asn112-Asp116-Gln123~([1]),homologous to the H~+-conducting motif of Asp85-Thr89-Asp96 in H~+ pump bacteriorhodopsin(BR)~([2]).     

Roles of HIV-1 auxiliary proteins in viral pathogenesis and host-pathogen interactions

INTRODUCTION In addition to the prototypical retroviral Gag, Pol, and Env proteins, HIV-1 produces six additional proteins, i.e., Tat, Rev, Nef, Vif, Vpr and Vpu (Fig. 1, adapted from [1]). While Tat and Rev are required for viral replication, Nef, Vif, V…     

Assessment and comparison of recombinant proteins from different sources for the detection of SARS-CoV-2 infection by using protein microarray

COVID-19 (the COVID-19 is a type of disease and resulted from being infected by virus SARS-CoV-2) pandemic is threatening tens of millions of lives around the world [1]. To date, specific drugs or vaccines are still not available for fighting the SARS-CoV-2. Diagnosis and quarantine are still the effective strategies for preventing the virus from spreading. Up to now, various detection methods for SARS-CoV-2 have been developed [2], which play critical roles in controlling the pandemics. According to the targets to be detected, these methods can be divided into three classes: methods for the nucleic acid [3], antigens [4], and antibodies elicited by the virus in the host [5]. Among these methods, the ones for antigens and antibodies could produce results in 10–15 min [6], which are suitable for point-of-care diagnosis, especially the ones for antibodies [7]. Meanwhile, the asymptomatic cases [8] and the false-negative results of nucleic acid testing [9] make the detection methods based on antibodies the best alternatives. The proteins, used in methods for detection of antibodies elicited by SARS-CoV-2 in the host, are critical agents, which could affect the diagnosis results. Given the strong immunogenicity of the nucleocapsid (N protein), spike protein (S protein), and related domains [10] and the potential diagnosis values, we collected 9 S1 proteins, 3 N proteins, 5 S2-related proteins, and receptor-binding domains (RBDs) from ACROBiosystems (Beijing, China), ABclonal (Wuhan, China), Novoprotein (Shanghai, China), Sino Biological (Beijing, China), and KactusBiosystems (Shanghai, China) and fabricated a protein microarray (Fig. 1A) to assess their diagnosis performance. In addition, other proteins such as the angiotensin converting enzyme 2 (ACE2), envelop protein (E), 3C-like protease, and papain-like protease were also included (Fig. 1B).     

The Saffold Virus-Penang 2B and 3C Proteins,but not the L Protein,Induce Apoptosis in HEp-2 and Vero Cells

Our previous work has shown that Saffold virus(SAFV) induced several rodent and primate cell lines to undergo apoptosis(Xu et al. in Emerg Microb Infect 3:1–8, 2014), but the essential viral proteins of SAFV involved in apoptotic activity lack study. In this study, we individually transfected the viral proteins of SAFV into HEp-2 and Vero cells to assess their ability to induce apoptosis, and found that the 2 B and 3 C proteins are proapoptotic. Further investigation indicated the transmembrane domain of the 2 B protein is essential for the apoptotic activity and tetramer formation of the 2 B protein. Our research provides clues for the possible mechanisms of apoptosis induced by SAFV in different cell lines. It also opens up new directions to study viral proteins(the 2 B, 3 C protein), and sets the stage for future exploration of any possible link between SAFV, inclusive of its related uncultivable genotypes, and multiple sclerosis.     

红凤菜和白子菜总黄酮含量的动态变化

红凤菜[Gynura bicolor (Willd. ) DC. ]和白子菜[G. divaricata (L. ) DC. ]均为菊三七属(Gynura Cass. )植物~([1]).红凤菜的嫩茎叶中含有丰富的营养成分,可作蔬菜食用~([2]);白子菜叶片在民间用于治疗糖尿病,动物实验证明其有显著的降血糖作用~([3]).     

Phosphoinositides as ligands of PHD-fingers: implications for chromatin remodeling

Phosphatidylinositol phosphates (PtdInsPs) play critical roles in signal transduction pathways, cytoskele-tal regulation, and vesicular trafficking and are implicated in multiple disease pathways. In the nucleus, PtdlnsPs have been found associated with chromatin, but their specific nuclear-binding proteins have not been identified. In a biochemical screen for PtdInsP-binding proteins, we identified a protein (ING2) containing a Plant Homeodomain (PHD) finger, a motif present in many chromatin- regulatory proteins. We show that the PHD domains of ING2 and of other diverse nuclear proteins bind to the rare PtdInsP species, phosphatidylinositol 5-phosphate (PtdIns(5)P). Further, we provide evidence for a functional interaction     

Interaction between Mnk2 and CBCVHL ubiquitin ligase E3 complex

MAP kinase-interacting kinase-2 (Mnk2) is one of the downstream kinases activated by MAP kinases. It phosphorylates the eukaryotic initiation factor 4E (elF4E), although the role of elF4E phosphorylation and the role of Mnk2 in the process of protein translation are not well understood. Except for elF4E, other physiological substrates of Mnk2 are still unidentified. To look for these unidentified substrates and to reveal the physiological function of Mnk2, we performed a yeast two-hybrid screening with Mnk2 as the bait. The results demonstrated Mnk2 could interact with VHL (von Hip-pel-Lindau tumor suppressor), Rbx1 (ring-box 1) and Cul2 (Cullin2) proteins in yeast cells. Furthermore, we validated the interaction between Mnk2 and VHL proteins in mammalian cells by co-immunoprecipitation analysis. Because the three proteins VHL, Rbx1 and Cul2 are all components of the CBCVHL ubiquitin ligase E3 complex, it has been shown that Mnk2 can interact with CBCVHL complex, and is probably one of the new substrates of the CBCVHL complex. Furthermore, during the interaction of Mnk2 with von Hippel-Lindau (VHL) tumor suppressor- binding protein 1 (VBP1), it appears that Mnk2 also joins to modulate cell shape as VBP1 plays an important role in the process of the maturation of the cytoskeleton and in the process of morphogenesis.     

Snake Venom C-Type Lectin Related Proteins Up-to-date

The research projects were supported by aresearch scholarship from the National Universityof Singapore,Singapore and by a fund from TheNational Bureau of Foreign Talents,China[2 0 0 1 -1 51 ] .1　 Introduction　　 L ectins are generally considered to be non-enzymatic proteins which selectively bind to spe-cific carbohydrate structure.Animal C- typelectins are a group of proteins which have carbo-hydrate- recognition domains (CRDs) in theirstructures and require calcium ion for their lig-…     

Open Sesame: treasure in store-operated calcium entry pathway for cancer therapy

Store-operated Ca2+ entry(SOCE) controls intracellular Ca2+ homeostasis and regulates a wide range of cellular events including proliferation,migration and invasion.The discovery of STIM proteins as Ca2+ sensors and Orai proteins as Ca2+ channel pore forming units provided molecular tools to understand the physiological function of SOCE.Many studies have revealed the pathophysiological roles of Orai and STIM in tumor cells.This review focuses on recent advances in SOCE and its contribution to tumorigenesis.Altered Orai and/or STIM functions may serve as biomarkers for cancer prognosis,and targeting the SOCE pathway may provide a novel means for cancer treatment.     

PLK1是DNA内切酶CtIP的新相互作用蛋白（英文）

正Dear Editor,DNA double-strand breaks caused by ionizing radiation are the most severe DNA damage types.If not being timely or correctly repaired,cells will undergo apoptosis or gene mutation and subsequent genomic instability~([1-2]).For double-strand breaks,there are two main repair pathway in cells,namely homologous recombination and non-homologous     

Direct insertion of proteins into a living cell using an atomic force microscope with a nanoneedle

We have developed a tool for directly inserting proteins into living cells by using atomic force microscopy (AFM) and an ultrathin needle, termed a nanoneedle. The surface of the nanoneedle was modified with His-tagged proteins using nickel chelating nitrilotriaceticacid (NTA). The fluorescent proteins, DsRed2-His₆ and EGFP-His₆, could be attached to and detached from the surface of the nanoneedle. These results suggest that the Ni-NTA modified nanoneedle can successfully be used for specific delivery of proteins. The nanoneedle modified with DsRed2-His₆ was able to penetrate the surface of a living HeLa cell, as confirmed by laser scanning fluorescence microscopy and monitoring an exerting force on the nanoneedle using AFM. Force curves using the nanoneedle indicated that the needle was able to penetrate at displacement speeds of 0.10–10 μm/s. These results suggest that this technique can be used to directly insert proteins into living cells and is applicable for modulation or regulation of single cell activity.     

Two-Dimensional Electrophoretic Analysis of Soluble Leaf Proteins of a Salt-sensitive(Triticum aestivum)and a Salt-tolerant(T.durum)Cultivar in Response to NaCl Stress

In this research, 3-day-old etiolated wheat seedlings of Triticum aestivum L. cv. Ceyhan-99 (salt-sensitive) and T. durumDesf. cv. Firat-93 (salt-tolerant) were grown in control and salt (150 mmol/L NaCI) treatments at a 15/25℃ temperatureregime in the light for 12 days. Soluble proteins extracted from the first leaf tissues of two cultivars were analyzed by two-dimensional (2-D) electrophoresis in order to detect NaCl-induced changes. The soluble leaf protein profiles of cultivarswere observed to be similar. However, quantitative differences in 74 proteins were detected in the salt treatment group,compared to the control. Among the 74 protein spots, 14 were common for two cultivars. As a result of NaCl treatment, twolow-molecular-weight (LMW) proteins (28.9 and 30.0 kDa) and one intermediate-molecular-weight (IMW) protein (44.3 kDa)in cv. Ceyhan-99 and six LMW proteins (18.6, 19.4, 25.7, 25.9, 26 and 27.6 kDa) in cv. Firat-93 were newly synthesized. Thenewly synthesized proteins were specific to each cultivar. In the Firat-93 cultivar, four proteins with LMW (24.8-27.9 kDa)were completely lost in NaCl treatment. Moreover, these four protein spots were not observed in both protein profiles ofcv. Ceyhan-99. Most of these proteins were in acidic character (pi<6.0-6.9) and low molecular weight (<31.6 kDa). It issuggested that the newly synthesized or completely lost LMW proteins may be important for cultivars differing in sensitivitytowards NaCl.     

粉尘螨组分在过敏性哮喘发生过程中的作用

正哮喘是一种临床上常见的慢性呼吸道疾病,其特点是病人气道反复阻塞和喘息,过敏性哮喘是其最常见的形式~([1]).据统计,全世界哮喘的发病率高达5%~16%,在美国全年用于哮喘的治疗费用超过了AIDS和肺结核治疗费用的总和~([2]).我国约有哮喘患者3000万人,哮喘已经成为危害我国人民健康的重大疾病~([3,4]).在众多吸入性过敏原中,尘螨是诱发呼吸道过敏最重要的因素,约有80%左右的哮喘患者对尘螨敏感~([5,6]).     

Proteomic Analysis of the Response of Liangyoupeijiu （Super High-Yield Hybrid Rice） Seedlings to Cold Stress

Liangyoupeijiu is a super high-yield hybrid rice. Despite its advantages with respect to yield and grain quality, it is sensitive to cold, which keeps it from being widely cultivated. We subjected Liangyoupeijiu seedlings to 4 ℃ cold treatment, then extracted the leaf proteins. After 2-D gel electrophoresis separation and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis, a series of differentially displayed proteins were identified. Some metabolism-associated proteins were found among the downregulated proteins, such as carbamoyl phosphate synthetase, transketolase 1, dihydrolipoamide dehydrogenase and glyceraldehyde 3-phosphate dehydrogenase. The upregulated proteins included both stress-resistance proteins such as nucleoside diphosphate kinase I and proteins that are negative for rice growth, such as FtsH-like protein, plastid fusion and/or translocation factor （Pftf） and actin. Our results indicate that cold may inhibit Liangyoupeijiu growth through decreasing metabolic activity and damaging cell structure.     

Computational Screening of Phase-separating Proteins

Phase separation is an important mechanism that mediates the compartmentalization of proteins in cells. Proteins that can undergo phase separation in cells share certain typical sequence features, like intrinsically disordered regions(IDRs) and multiple modular domains. Sequencebased analysis tools are commonly used in the screening of these proteins. However, current phase separation predictors are mostly designed for IDR-containing proteins, thus inevitably overlook the phase-separating proteins with relatively low IDR content. Features other than amino acid sequence could provide crucial information for identifying possible phase-separating proteins: protein–protein interaction(PPI) networks show multivalent interactions that underlie phase separation process; post-translational modifications(PTMs) are crucial in the regulation of phase separation behavior; spherical structures revealed in immunofluorescence(IF) images indicate condensed droplets formed by phase-separating proteins, distinguishing these proteins from non-phaseseparating proteins. Here, we summarize the sequence-based tools for predicting phaseseparating proteins and highlight the importance of incorporating PPIs, PTMs, and IF images into phase separation prediction in future studies.