1.In situ Analytical Techniques for Membrane Protein Interactions
Zi-Yuan KANG ; Tong YU ; Chao LI ; Xue-Hua ZHANG ; Jun-Hui GUO ; Qi-Chang LI ; Jing-Xing GUO ; Hao XIE
Progress in Biochemistry and Biophysics 2025;52(5):1206-1218
Membrane proteins are integral components of cellular membranes, accounting for approximately 30% of the mammalian proteome and serving as targets for 60% of FDA-approved drugs. They are critical to both physiological functions and disease mechanisms. Their functional protein-protein interactions form the basis for many physiological processes, such as signal transduction, material transport, and cell communication. Membrane protein interactions are characterized by membrane environment dependence, spatial asymmetry, weak interaction strength, high dynamics, and a variety of interaction sites. Therefore, in situ analysis is essential for revealing the structural basis and kinetics of these proteins. This paper introduces currently available in situ analytical techniques for studying membrane protein interactions and evaluates the characteristics of each. These techniques are divided into two categories: label-based techniques (e.g., co-immunoprecipitation, proximity ligation assay, bimolecular fluorescence complementation, resonance energy transfer, and proximity labeling) and label-free techniques (e.g., cryo-electron tomography, in situ cross-linking mass spectrometry, Raman spectroscopy, electron paramagnetic resonance, nuclear magnetic resonance, and structure prediction tools). Each technique is critically assessed in terms of its historical development, strengths, and limitations. Based on the authors’ relevant research, the paper further discusses the key issues and trends in the application of these techniques, providing valuable references for the field of membrane protein research. Label-based techniques rely on molecular tags or antibodies to detect proximity or interactions, offering high specificity and adaptability for dynamic studies. For instance, proximity ligation assay combines the specificity of antibodies with the sensitivity of PCR amplification, while proximity labeling enables spatial mapping of interactomes. Conversely, label-free techniques, such as cryo-electron tomography, provide near-native structural insights, and Raman spectroscopy directly probes molecular interactions without perturbing the membrane environment. Despite advancements, these methods face several universal challenges: (1) indirect detection, relying on proximity or tagged proxies rather than direct interaction measurement; (2) limited capacity for continuous dynamic monitoring in live cells; and (3) potential artificial influences introduced by labeling or sample preparation, which may alter native conformations. Emerging trends emphasize the multimodal integration of complementary techniques to overcome individual limitations. For example, combining in situ cross-linking mass spectrometry with proximity labeling enhances both spatial resolution and interaction coverage, enabling high-throughput subcellular interactome mapping. Similarly, coupling fluorescence resonance energy transfer with nuclear magnetic resonance and artificial intelligence (AI) simulations integrates dynamic structural data, atomic-level details, and predictive modeling for holistic insights. Advances in AI, exemplified by AlphaFold’s ability to predict interaction interfaces, further augment experimental data, accelerating structure-function analyses. Future developments in cryo-electron microscopy, super-resolution imaging, and machine learning are poised to refine spatiotemporal resolution and scalability. In conclusion, in situ analysis of membrane protein interactions remains indispensable for deciphering their roles in health and disease. While current technologies have significantly advanced our understanding, persistent gaps highlight the need for innovative, integrative approaches. By synergizing experimental and computational tools, researchers can achieve multiscale, real-time, and perturbation-free analyses, ultimately unraveling the dynamic complexity of membrane protein networks and driving therapeutic discovery.
2.N-butyl-9H-pyrimido4,5-bindole-2-carboxamide inhibits macrophage foaming and pyroptosis via NLRP3/caspase-1
Zhi-Yun SHU ; Zi-Xu HUYAN ; Wen-Qing ZHANG ; Shi-Shun XIE ; Hong-Yuan CHENG ; Guo-Xing XU ; Xiang-Jun LI
Chinese Pharmacological Bulletin 2024;40(6):1035-1041
Aim To design the pyrimidoindole deriva-tive N-butyl-9H-pyrimido[4,5-b]indole-2-carboxamide(BFPI)and synthesize it to investigate whether it in-hibits macrophage pyroptosis and foaming effects through the NLRP3/Caspase-1 pathway.Methods BFPI was synthesized using 2,4,6-triethoxycarbonyl-l,3,5-triazine and 2-aminoindole as starting materials and structurally characterized by 1H NMR,13C NMR,and ESI-MS.The in vitro cultured mouse monocyte macro-phage cell line RAW264.7 was divided into blank,model(PA)and therapeutic(BFPI)groups,and the cells in each group were treated with the corresponding culture medium for 24 h.The proliferative viability was detected by MTT assay,and the formation of intracel-lular lipid droplets was detected by oil red O staining,and NLRP3 was detected by Western-blot and RT-qPCR,caspase-1 and MCP-1 mRNA and protein ex-pression levels by Western blot and RT-qPCR.Results Compared with the blank group,the proliferation vi-ability of cells in the model group significantly de-creased and the formation of lipid droplets significantly increased;compared with the model group,the prolif-eration viability of cells in the treatment group signifi-cantly increased and the formation of lipid droplets sig-nificantly decreased,and the differences were statisti-cally significant(P<0.01);compared with the blank group,the cellular NLRP3,caspase-1 and MCP-1 mR-NA and protein expression levels of cells in the model group significantly increased;compared with the model group,the expression levels of the above indexes of the cells in the treatment group significantly decreased,and the difference was statistically significant(P<0.01).Conclusions BFPI contributes to delaying macrophage-derived foam cell formation during athero-genesis by inhibiting macrophage NLRP3,caspase-1,and MCP-1 expression and thereby promoting their pro-liferation and inhibiting lipid phagocytosis.
3.Digital study on proximal clavicle anatomical plate based on 3D printing technology
Yi ZHENG ; Xing-Guo ZHENG ; Jia-Kai ZHANG ; Jun-Long WU ; Xin-Hua YUAN
China Journal of Orthopaedics and Traumatology 2024;37(3):278-280
Objective To explore feasibility of 3D metal printing technology combined with virtual design proximal clavicle anatomical plate.Methods A 52-year-old male healthy volunteer was retrospectively selected to design proximal clavicle anatomical plate system by using Mimics15.01,NX12.0 and other software.STL data were input into 3D printer to print 1∶1 clavicle model and proximal clavicle anatomical plate.The fit of the plate was tested in vitro and the accuracy of screw position was evaluated by imaging.Printing time of model,nail path design and fabrication time of the anatomical plate at proximal clavicle were recorded.Results The 3D metal printing proximal clavicle anatomical plate fitted well to clavicle model,orienta-tion of proximal clavicle locking screw was accurate,and X-ray and CT scan showed the screw position was good.Printing time of model,the time of nail path design,and the time of making anatomical plate of proximal clavicle were 120,15 and 300 min respectively.Conclusion The proximal clavicular anatomical plate system based on 3D metal printing technology could achieve good lamination of proximal clavicular fracture plate and precise screw placement,providing a new and accurate surgical method for the treatment of the proximal clavicular fracture.
4.Porcine SIRT5 promotes replication of foot and mouth disease virus type O in PK-15 cells
Guo-Hui CHEN ; Xi-Juan SHI ; Xin-Tian BIE ; Xing YANG ; Si-Yue ZHAO ; Da-Jun ZHANG ; Deng-Shuai ZHAO ; Wen-Qian YAN ; Ling-Ling CHEN ; Mei-Yu ZHAO ; Lu HE ; Hai-Xue ZHENG ; Xia LIU ; Ke-Shan ZHANG
Chinese Journal of Zoonoses 2024;40(5):421-429
The effect of porcine SIRT5 on replication of foot and mouth disease virus type O(FMDV-O)and the underlying regulatory mechanism were investigated.Western blot and RT-qPCR analyses were employed to monitor expression of endoge-nous SIRT5 in PK-15 cells infected with FMDV-O.Three pairs of SIRT5-specific siRNAs were synthesized.Changes to SIRT5 and FMDV-O protein and transcript levels,in addition to virus copy numbers,were measured by western blot and RT-qPCR analyses.PK-15 cells were transfected with a eukaryotic SIRT5 expression plasmid.Western blot and RT-qPCR analyses were used to explore the impact of SIRT5 overexpression on FMDV-O replication.Meanwhile,RT-qPCR analysis was used to detect the effect of SIRT5 overexpression on the mRNA expression levels of type I interferon-stimulated genes induced by SeV and FMDV-O.The results showed that expression of SIRT5 was up-regulated in PK-15 cells infected with FMDV-O and siRNA interfered with SIRT5 to inhibit FMDV-O replication.SIRT5 overexpression promoted FMDV-O replication.SIRT5 over-expression decreased mRNA expression levels of interferon-stimulated genes induced by SeV and FMDV-O.These results suggest that FMDV-O infection stimulated expression of SIRT5 in PK-15 cells,while SIRT5 promoted FMDV-O rep-lication by inhibiting production of type I interferon-stimula-ted genes.These findings provide a reference to further ex-plore the mechanism underlying the ability of porcine SIRT5 to promote FMDV-O replication.
5.Functional Studies on the Regulation of Flowering by PfFT3,a Member of the Perilla PEBP Gene Family
Qi-Feng WANG ; Xiao-Yan FENG ; Hui LI ; Fu-Peng HOU ; Xi GUO ; Jun-Xing LU ; Jian HU ; Tao ZHANG
Chinese Journal of Biochemistry and Molecular Biology 2024;40(8):1173-1184
Perilla frutescens,a short-day plant,is rich in biologically active substances and nutrients.Current research on Perilla frutescens focuses on agronomic traits such as yield and fatty acid accumula-tion,with limited exploration of the flowering process and floral organ development.The molecular regu-latory mechanisms underlying these aspects remain unclear.FLOWERING LOUC T(FT)is a florigen in Arabidopsis,plays critical roles in floral transition.PfFT3 is unannotated by genome but annotated by transcriptomics data to the FT-like subfamily.Its function in controlling flowering is yet to be explored.Here subcellular localization analysis showed that PfFT3 is localized in the nucleus and cytoplasm.The plant over-expression vector pCAMBIAI1303-PfFT3 was constructed and transformed into wild-type(Col-0)and mutant fd-2,fd-3,and ft-10 plants by agrobacterium-mediated inflorescence infiltration as a means of obtaining genetically stable and pure overexpression and backfill transgenic lines in Arabidopsis,respectively.Analysis of the results showed that overexpression of PfFT3 significantly promoted early flowering in Arabidopsis and rescued the late-flowering phenotype of the mutants fd-2,fd-3,and ft-10,and that expression of the exogenous PfFT3 promoted the expression of the downstream endogenous flow-ering genes AtSOC1,AtAP1,AtFUL,and AtLFY.This study demonstrates the positive role of PfFT3 in promoting flowering,providing a foundation for further investigation of PfPEBP function and advancing the breeding of early-flowering Perilla frrutescens cultivars.
6.Clinical Observation on Haploid Hematopoietic Stem Cells Combined with Umbilical Cord Blood Double Transplantation for Aplastic Anaemia in Children
Huan-Jun LIU ; Xing-Hua CHEN ; Wen-Bang ZHANG ; Shu-Xia GUO
Journal of Experimental Hematology 2024;32(3):890-895
Objective:To explore the efficacy and safety of haploidentical hematopoietic stem cell transplantation combined with umbilical cord blood infusion for the treatment of aplastic anaemia in children.Methods:Nine cases of children with aplastic anaemia treated with umbilical cord blood combined with haploidentical hematopoietic stem cell transplantation at the People's Hospital of Henan University of Chinese Medicine from January 1,2021 to September 15,2023 with a median age of 11(2-13)years and a median follow up of 18(7.5-21)months were included,and the clinical data were retrospectively analyzed.Hematopoiesis reconstitution,the incidence of graft-versus-host disease(GVHD),infections and survival of the patients were analyzed.Results:All 9 children were successfully implanted.The median time to neutrophil and platelet implantation was 11.11±1.27 d and 12.44±3.36 d,respectively.One case developed acute gastrointestinal GVHD of degree I,which was improved after treatment,and the patient developed superficial gastritis and chronic gastrointestinal GVHD at a later stage,which is currently under clinical follow-up.Acute GVHD of Ⅱ-Ⅳ degree was 0%.Hemorrhagic cystitis in 3 cases,CMV infection in 5 cases and bacterial and fungal infections in 5 cases improved with symptomatic treatment.All 9 children demonstrated complete donor chimerism within 1 month after transplantation,at two years of follow-up,all nine children survived without recurrence or development of grade Ⅱ-Ⅳ GVHD,and there were no children with transplant-related deaths.Conclusion:Haploidentical hematopoietic stem cell transplantation combined with umbilical cord blood transfusion for aplastic anaemia in children has a low incidence and mild degree of GVHD,with significant efficacy,and can be used as a therapeutic option for children without an HLA full donor chimeric match.
7.A multicenter study of neonatal stroke in Shenzhen,China
Li-Xiu SHI ; Jin-Xing FENG ; Yan-Fang WEI ; Xin-Ru LU ; Yu-Xi ZHANG ; Lin-Ying YANG ; Sheng-Nan HE ; Pei-Juan CHEN ; Jing HAN ; Cheng CHEN ; Hui-Ying TU ; Zhang-Bin YU ; Jin-Jie HUANG ; Shu-Juan ZENG ; Wan-Ling CHEN ; Ying LIU ; Yan-Ping GUO ; Jiao-Yu MAO ; Xiao-Dong LI ; Qian-Shen ZHANG ; Zhi-Li XIE ; Mei-Ying HUANG ; Kun-Shan YAN ; Er-Ya YING ; Jun CHEN ; Yan-Rong WANG ; Ya-Ping LIU ; Bo SONG ; Hua-Yan LIU ; Xiao-Dong XIAO ; Hong TANG ; Yu-Na WANG ; Yin-Sha CAI ; Qi LONG ; Han-Qiang XU ; Hui-Zhan WANG ; Qian SUN ; Fang HAN ; Rui-Biao ZHANG ; Chuan-Zhong YANG ; Lei DOU ; Hui-Ju SHI ; Rui WANG ; Ping JIANG ; Shenzhen Neonatal Data Network
Chinese Journal of Contemporary Pediatrics 2024;26(5):450-455
Objective To investigate the incidence rate,clinical characteristics,and prognosis of neonatal stroke in Shenzhen,China.Methods Led by Shenzhen Children's Hospital,the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022.The incidence,clinical characteristics,treatment,and prognosis of neonatal stroke in Shenzhen were analyzed.Results The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137,1/6 060,and 1/7 704,respectively.Ischemic stroke accounted for 75%(27/36);boys accounted for 64%(23/36).Among the 36 neonates,31(86%)had disease onset within 3 days after birth,and 19(53%)had convulsion as the initial presentation.Cerebral MRI showed that 22 neonates(61%)had left cerebral infarction and 13(36%)had basal ganglia infarction.Magnetic resonance angiography was performed for 12 neonates,among whom 9(75%)had involvement of the middle cerebral artery.Electroencephalography was performed for 29 neonates,with sharp waves in 21 neonates(72%)and seizures in 10 neonates(34%).Symptomatic/supportive treatment varied across different hospitals.Neonatal Behavioral Neurological Assessment was performed for 12 neonates(33%,12/36),with a mean score of(32±4)points.The prognosis of 27 neonates was followed up to around 12 months of age,with 44%(12/27)of the neonates having a good prognosis.Conclusions Ischemic stroke is the main type of neonatal stroke,often with convulsions as the initial presentation,involvement of the middle cerebral artery,sharp waves on electroencephalography,and a relatively low neurodevelopment score.Symptomatic/supportive treatment is the main treatment method,and some neonates tend to have a poor prognosis.
8.Clinical and genetic features of children with 3-methylcrotonyl-coenzyme A carboxylase deficiency:an analysis of six cases
Li-Ming ZHANG ; Sheng-Nan WU ; Ya-Nan GUO ; Jian-Wei YANG ; Hong-Qi SUN ; Jun-Mei YANG ; Yong-Xing CHEN
Chinese Journal of Contemporary Pediatrics 2024;26(8):845-851
Objective To investigate the clinical and genetic features of children with 3-methylcrotonyl-coenzyme A carboxylase deficiency(MCCD).Methods A retrospective analysis was conducted on the clinical manifestations and genetic testing results of six children with MCCD who attended Children's Hospital Affiliated to Zhengzhou University from January 2018 to October 2023.Results Among the six children with MCCD,there were 4 boys and 2 girls,with a mean age of 7 days at the time of attending the hospital and 45 days at the time of confirmed diagnosis.Of all children,one had abnormal urine odor and five had no clinical symptoms.All six children had increases in blood 3-hydroxyisovaleryl carnitine and urinary 3-hydroxyisovaleric acid and 3-methylcrotonoylglycine,and five of them had a reduction in free carnitine.A total of six mutations were identified in the MCCC1 gene,i.e.,c.1630del(p.R544Dfs*2),c.269A>G(p.D90G),c.1609T>A(p.F537I),c.639+2T>A,c.761+1G>T,and c.1331G>A(p.R444H),and three mutations were identified in the MCCC2 gene,i.e.,c.838G>T(p.D280Y),c.592C>T(p.Q198*,366),and c.1342G>A(p.G448A).Among these mutations,c.269A>G(p.D90G)and c.1609T>A(p.F537I)had not been previously reported in the literature.There was one case of maternal MCCD,and the child carried a heterozygous mutation from her mother.Five children with a reduction in free carnitine were given supplementation of L-carnitine,and free carnitine was restored to the normal level at the last follow-up visit.Conclusions This study identifies two new mutations,c.269A>G(p.D90G)and c.1609T>A(p.F537I),thereby expanding the mutation spectrum of the MCCC1 gene.A combination of blood amino acid and acylcarnitine profiles,urine organic acid analysis,and genetic testing can facilitate early diagnosis and treatment of MCCD,and provide essential data for genetic counseling.
9.Antimicrobial resistance of bacteria from blood specimens:surveillance re-port from Hunan Province Antimicrobial Resistance Surveillance System,2012-2021
Hong-Xia YUAN ; Jing JIANG ; Li-Hua CHEN ; Chen-Chao FU ; Chen LI ; Yan-Ming LI ; Xing-Wang NING ; Jun LIU ; Guo-Min SHI ; Man-Juan TANG ; Jing-Min WU ; Huai-De YANG ; Ming ZHENG ; Jie-Ying ZHOU ; Nan REN ; An-Hua WU ; Xun HUANG
Chinese Journal of Infection Control 2024;23(8):921-931
Objective To understand the change in distribution and antimicrobial resistance of bacteria isolated from blood specimens of Hunan Province,and provide for the initial diagnosis and treatment of clinical bloodstream infection(BSI).Methods Data reported from member units of Hunan Province Antimicrobial Resistance Survei-llance System from 2012 to 2021 were collected.Bacterial antimicrobial resistance surveillance method was imple-mented according to the technical scheme of China Antimicrobial Resistance Surveillance System(CARSS).Bacteria from blood specimens and bacterial antimicrobial susceptibility testing results were analyzed by WHONET 5.6 soft-ware and SPSS 27.0 software.Results A total of 207 054 bacterial strains were isolated from blood specimens from member units in Hunan Province Antimicrobial Resistance Surveillance System from 2012 to 2021,including 107 135(51.7%)Gram-positive bacteria and 99 919(48.3%)Gram-negative bacteria.There was no change in the top 6 pathogenic bacteria from 2012 to 2021,with Escherichia coli(n=51 537,24.9%)ranking first,followed by Staphylococcus epidermidis(n=29 115,14.1%),Staphylococcus aureus(n=17 402,8.4%),Klebsiella pneu-moniae(17 325,8.4%),Pseudomonas aeruginosa(n=4 010,1.9%)and Acinetobacter baumannii(n=3 598,1.7%).The detection rate of methicillin-resistant Staphylococcus aureus(MRSA)decreased from 30.3%in 2015 to 20.7%in 2021,while the detection rate of methicillin-resistant coagulase-negative Staphylococcus(MRCNS)showed an upward trend year by year(57.9%-66.8%).No Staphylococcus was found to be resistant to vancomy-cin,linezolid,and teicoplanin.Among Gram-negative bacteria,constituent ratios of Escherichia coli and Klebsiella pneumoniae were 43.9%-53.9%and 14.2%-19.5%,respectively,both showing an upward trend(both P<0.001).Constituent ratios of Pseudomonas aeruginosa and Acinetobacter baumannii were 3.6%-5.1%and 3.0%-4.5%,respectively,both showing a downward trend year by year(both P<0.001).From 2012 to 2021,resistance rates of Escherichia coli to imipenem and ertapenem were 1.0%-2.0%and 0.6%-1.1%,respectively;presenting a downward trend(P<0.001).The resistant rates of Klebsiella pneumoniae to meropenem and ertapenem were 7.4%-13.7%and 4.8%-6.4%,respectively,presenting a downward trend(both P<0.001).The resistance rates of Pseudomonas aeruginosa and Acinetobacter baumannii to carbapenem antibiotics were 7.1%-15.6%and 34.7%-45.7%,respectively.The trend of resistance to carbapenem antibiotics was relatively stable,but has de-creased compared with 2012-2016.The resistance rates of Escherichia coli to the third-generation cephalosporins from 2012 to 2021 were 41.0%-65.4%,showing a downward trend year by year.Conclusion The constituent ra-tio of Gram-negative bacillus from blood specimens in Hunan Province has been increasing year by year,while the detection rate of carbapenem-resistant Gram-negative bacillus remained relatively stable in the past 5 years,and the detection rate of coagulase-negative Staphylococcus has shown a downward trend.
10.Antimicrobial resistance of bacteria from cerebrospinal fluid specimens:surveillance report from Hunan Province Antimicrobial Resistance Survei-llance System,2012-2021
Jun LIU ; Li-Hua CHEN ; Chen-Chao FU ; Chen LI ; Yan-Ming LI ; Xing-Wang NING ; Guo-Min SHI ; Jing-Min WU ; Huai-De YANG ; Hong-Xia YUAN ; Ming ZHENG ; Nan REN ; An-Hua WU ; Xun HUANG ; Man-Juan TANG
Chinese Journal of Infection Control 2024;23(8):932-941
Objective To investigate changes in the distribution and antimicrobial resistance of bacteria isolated from cerebrospinal fluid(CSF)specimens in Hunan Province,and provide reference for correct clinical diagnosis and rational antimicrobial use.Methods Data reported by member units of Hunan Province Antimicrobial Resistance Surveillance System from 2012 to 2021 were collected according to China Antimicrobial Resistance Surveillance Sys-tem(CARSS)technical scheme.Data of bacteria isolated from CSF specimens and antimicrobial susceptibility tes-ting results were analyzed with WHONET 5.6 and SPSS 20.0 software.Results A total of 11 837 bacterial strains were isolated from CSF specimens from member units of Hunan Province Antimicrobial Resistance Surveillance Sys-tem from 2012 to 2021.The top 5 strains were coagulase-negative Staphylococcus(n=6 397,54.0%),Acineto-bacter baumannii(n=764,6.5%),Staphylococcus aureus(n=606,5.1%),Enterococcus faecium(n=465,3.9%),and Escherichia coli(n=447,3.8%).The detection rates of methicillin-resistant coagulase-negative Staphyloco-ccus(MRCNS)and methicillin-resistant Staphylococcus aureus(MRSA)were 58.9%-66.3%and 34.4%-62.1%,respectively.No Staphylococcus spp.were found to be resistant to vancomycin,linezolid,and teicoplanin.The de-tection rate of Enterococcus faecium was higher than that of Enterococcus faecalis,and the resistance rates of En-terococcus f aecium to penicillin,ampicillin,high concentration streptomycin and levofloxacin were all higher than those of Enterococcus faecalis(all P=0.001).Resistance rate of Streptococcus pneumoniae to penicillin was 85.0%,at a high level.Resistance rate of Escherichia coli to ceftriaxone was>60%,while resistance rates to enzyme inhibitors and carbapenem antibiotics were low.Resistance rate of Klebsiella pneumoniae to ceftriaxone was>60%,to en-zyme inhibitors piperacillin/tazobactam and cefoperazone/sulbactam was>30%,to carbapenem imipenem and me-ropenem was about 30%.Resistance rates of Acinetobacter baumannii to most tested antimicrobial agents were>60%,to imipenem and meropenem were 59.0%-79.4%,to polymyxin B was low.Conclusion Among the bac-teria isolated from CSF specimens,coagulase-negative Staphylococcus accounts for the largest proportion,and the overall resistance of pathogenic bacteria is relatively serious.Bacterial antimicrobial resistance surveillance is very important for the effective treatment of central nerve system infection.

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