1.Exploration of bioinformatics courses for eight-year medical students
Lingyun ZOU ; Qingshan NI ; Xiaolin JIN ; Xiancai RAO ; Fuquan. HU
Chinese Journal of Medical Education Research 2011;10(12):1428-1430
The need of eight-year clinical students for bioinformatics undergraduate courses is described.In addition,the measures and experiences on textbooks choosing,teaching content assignment,teaching methods designing and test means innovation are also discussed.All these provide a reference implementation for the development of eight-year clinical bioinformatics courses.
2.Acute toxicity of intravenous isoflurane in Beagles
Aijie LIU ; Wensheng ZHANG ; Hanxiang MA ; Xiaolin YANG ; Zongbin YANG ; Yan RAO ; Nanfu LUO ; Jin LIU
Chinese Journal of Anesthesiology 2010;30(7):772-773
Objective To investigate the acute toxicity of intravenous isoflurane in Beagles.Methods Six healthy adult Beagles of both sexes aged 6-8 months weighing 6-8 kg were used in this study.Isoflurane injectio (120 mg/ml) in 30% hpid emulsion was injected intravenously. Femoral artery was cannulated for direct BP monitoring.ECG was continuously monitored.The maximal tolerance dose (MTD) and approximate lethal dose (ALD) were determined by up-and-down technique. The initial dose was 3.0 ml/kg. The dose was decreased/increased by 0.3 ml/kg if the previous animal died/survived.The survived dogs were observed for 2 weeks.Autopsy and histopathological examination were performed on all dead Beagles.Results The ALD and MTD of intravenous isoflurane were 252 and 216 mg/kg. Autopsy and histopathological examination did not show any abnormality.Conclusion Cardiopulmonary depression is the main manifestation of the acute toxicity of intravenous isoflurane in Beagles.
3.Molecular modeling of peptide antibiotics hPAB-?and its artificial mutants construction
Xiancai RAO ; Xiaolin JIN ; Shu LI ; Jinchuan HU ; Xiaomei HU ; Zhijin CHEN ; Fuquan HU ;
Journal of Medical Postgraduates 2003;0(09):-
Objectives: To design the mutants of peptide antibiotics hPAB ? based on its molecular structure. Methods: The three dimension structure of hPAB ? was constructed by protein homology modeling method. The mutant molecules were designed and generated by PCR and inserted into pQE CP4 expression plasmid. The recombinant plasmids were identified by PCR and DNA sequencing and then transformed into Escherichia coli JM109 to express target fusion proteins. Results:Peptide hPAB ? shows one ? helical and three ? sheet in its structure. Its ? helical regions seem play a key role in the formation of active oligomer. Aside from positioning Thr 7 and Lys 10 into contact positions, the orientation of the ? helix is conserved about the oligome core, forming a ridge around it. Additionally, the dipoles of the helices would overlap to create a positively charged region near the core. These dipoles may be offset, however, by the presence of Asp 4 at the base of the helix. Two mutant molecules, hPAB ? 38 and hPAB ? 34, were designed by deleting N or/and C terminal 2~5 amino acid residues based on hPAB ? structure. The recombinant plasmids containing the mutants gene can express interest fusion proteins in E. coli JM109 successfully. Conclusions: Design, cloning and expression of the mutants of peptide antibiotics hPAB ? lay down the foundation for screening of the mutant of shorter peptide chain and having high or same antimicrobial activity.
4.Screening of recombinant bacterium for expression of human peptide antibiotic hPAB-? multimers and evaluation of its fermentation
Jinchuan HU ; Zhengqing WANG ; Xiaolin JIN ; Shu LI ; Yinling TAN ; Ming LI ; Xiaodong SHEN ; Chun ZHANG ; Fuquan HU ; Xiancai RAO
Journal of Medical Postgraduates 2003;0(03):-
Objective: To screen the best genetic engineering bacterium for the production of peptide antibiotic hPAB-? and evaluate its fermentation level in bottle. Methods:After analysis of the interest fusion protein expression levels of 8 recombinant bacteria containing 1-8 copies of human peptide antibiotic hPAB-? expressing plasmid respectively,2-5 copies expressing bacteria were chosen for the further study of their bacteria yield,expression forms of the target protein, dissolution of the inclusion bodies and the efficiency of fusion protein purification by affinity chromatography, then the best engineering bacterium with the certain copies of interest peptide expressing plasmid was screened out and its optimal fermentation parameters in bottle were also studied. Results:The recombinant bacterium transformed by 3 copies of interest peptide expressing plasmid was the best candidate for its bacteria yield (3.153 g/L) and fusion protein expression level (27.7%) were the highest among 1-8 copies candidates. The inclusion bodies of 3 copies target fusion protein could be easily dissolved by 8 mol/L urea and captured by Ni-NTA column. The elution of the fusion protein could be directly cleaved to monomer by adding 2 mol/L hydroxylamine, adjusting pH to 9.0 and incubating at 45℃ for 2 h. The optimal fermentation conditions of the selected recombinant bacteria were: culture the organisms with modified M9-CAA media at 37℃ and 160 r/min to (A 600 )≈2.5, then add IPTG to the final concentration 100 ?mol/L to induce the expression of target fusion protein for 5 h. Conclusion:The engineering bacterium containing 3 copies interest peptide recombinant expressing plasmid is the best candidate for the production of peptide antibiotic hPAB-?,and its fermentation parameters are confirmed.
5.Cloning of LVA Ca 2+ channel and its primary structure features
Fuquan HU ; Xiaolin JIN ; Xiancai RAO ; Kebin ZHANG ; Xiaomei HU ; Qifu LIU ; Zhuang HE′AN ; Bhattachajee ARIN ; Zhang MIN ; Li MING
Journal of Cellular and Molecular Immunology 2001;17(1):8-12
Aim To clone LVA calcium channel (also known as T-type calcium channel) from INS-1 cell line derived from rat pancreatic β cells. Methods RT-PCR, 3′ -RACE and 5′ -RACE were used to clone coding sequence of the whole gene. DNA sequencing and genomic DNA walking were used to identify the primary structure features and exons. Results The cloned gene, named as α 1 G-INS, was composed of 6 864 bp, encoding 2 288 amino acids, which shares 96.3% identity to α 1G, the neuronal T-type calcium channel. Compared to α 1G, the amino acids in membrane-spanning regions of four transmembrane domains and intracellular loop LI-II of α 1G-INS were highly conserved, but there are three distinct regions. This discrepancy was due to alternative mRNA splicing. Scattering on other regions of the molecule there were 10 single amino acid substitutions, which could be explained as site-mutations of the gene. Conclusion A new isoform,α 1G-INS, of T-type calcium channel is successfully cloned from rat insulin-secreting cell line INS-1, which is significant to further understanding many Ca2+ -involved biologically essential processes.
6.The mechanism of bone morphogenetic protein 2 regulating pulmonary vascular remodeling in pulmonary hypertension
Jingyi MAI ; Xiaolin RAO ; Yong CAI ; Shunna LIN
Chinese Journal of Postgraduates of Medicine 2023;46(8):763-768
Objective:To explore the mechanism of bone morphogenetic protein 2 (BMP-2) regulating pulmonary vascular remodeling in pulmonary hypertension (PH).Methods:Pulmonary artery smooth muscle cells (PASMC) groups: control group, PH group, PH+BMP-2 group, PH+BMP-2+ small interfering BMP receptor(si-BMPR)-Ⅰa group, PH+BMP-2+ si-BMPR-Ⅰb group, PH+BMP -2+si-BMPR-Ⅱ group. In vitro PH model was induced by hypoxia. The three BMP-2 receptors were silenced by the transfection of si-BMPR-Ⅰa, si-BMPR-Ⅰb and si-BMPR-Ⅱ plasmids, respectively. Cell proliferation and apoptosis in each group were detected, transient receptor potential ion channel C1/6 (TRPC1/6), p21 mRNA and protein levels, and intracellular Ca 2+ concentration were detected. Results:The intracellular Ca 2+ concentration in the PH group was higher than that in the control group: (785.15 ± 44.26) nmol/L vs. (224.15 ± 15.87) nmol/L, the and apoptosis rate was lower than that in the control group: (3.15 ± 0.22)% vs. (7.31 ± 0.45)%, there were statistical differences ( P<0.05). The intracellular Ca 2+ concentration in the PH+BMP-2 group was (297.64 ± 21.46) nmol/L, and was lower than that in the PH group, and apoptosis rate was (6.88 ± 0.75)%, and was higher than that in the PH group, there were statistical differences ( P<0.05). The intracellular Ca 2+ concentration in the PH+BMP-2+si-BMPR-Ⅰa group, PH+BMP-2+ si-BMPR-Ⅰb group, PH+BMP -2+si-BMPR-Ⅱ group was (412.31 ± 29.57), (384.34 ± 30.66), (695.23 ± 39.85) nmol/L, and was higher than that in the PH+BMP-2 group, and apoptosis rate was (4.10 ± 0.27)%, (4.26 ± 0.28)%, (3.33 ± 0.24)%, and was lower than that in the PH+BMP-2 group, there were statistical differences ( P<0.05). The intracellular Ca 2+ concentration in the PH+BMP -2+si-BMPR-Ⅱ group was higher than that in the PH+BMP-2+si-BMPR-Ⅰa group and PH+BMP-2+ si-BMPR-Ⅰb group, the apoptosis rate was lower than that in the PH+BMP-2+si-BMPR-Ⅰa group and PH+BMP-2+ si-BMPR-Ⅰb group, there were statistical differences ( P<0.05). Conclusions:BMP-2 mainly inhibits the expression of TRPC1/6 by interacting with the receptor BMPR-Ⅱ, inhibits the influx of Ca 2+ and promotes the expression of p21, thereby inhibiting the proliferation of PASMC and promoting apoptosis, participating in pulmonary vascular remodeling in PH.
7.Cryo-EM structures for the Mycobacterium tuberculosis iron-loaded siderophore transporter IrtAB.
Shan SUN ; Yan GAO ; Xiaolin YANG ; Xiuna YANG ; Tianyu HU ; Jingxi LIANG ; Zhiqi XIONG ; Yuting RAN ; Pengxuan REN ; Fang BAI ; Luke W GUDDAT ; Haitao YANG ; Zihe RAO ; Bing ZHANG
Protein & Cell 2023;14(6):448-458
The adenosine 5'-triphosphate (ATP)-binding cassette (ABC) transporter, IrtAB, plays a vital role in the replication and viability of Mycobacterium tuberculosis (Mtb), where its function is to import iron-loaded siderophores. Unusually, it adopts the canonical type IV exporter fold. Herein, we report the structure of unliganded Mtb IrtAB and its structure in complex with ATP, ADP, or ATP analogue (AMP-PNP) at resolutions ranging from 2.8 to 3.5 Å. The structure of IrtAB bound ATP-Mg2+ shows a "head-to-tail" dimer of nucleotide-binding domains (NBDs), a closed amphipathic cavity within the transmembrane domains (TMDs), and a metal ion liganded to three histidine residues of IrtA in the cavity. Cryo-electron microscopy (Cryo-EM) structures and ATP hydrolysis assays show that the NBD of IrtA has a higher affinity for nucleotides and increased ATPase activity compared with IrtB. Moreover, the metal ion located in the TM region of IrtA is critical for the stabilization of the conformation of IrtAB during the transport cycle. This study provides a structural basis to explain the ATP-driven conformational changes that occur in IrtAB.
Siderophores/metabolism*
;
Iron/metabolism*
;
Mycobacterium tuberculosis/metabolism*
;
Cryoelectron Microscopy
;
Adenosine Triphosphate/metabolism*
;
ATP-Binding Cassette Transporters
8.Cryo-EM structures of a prokaryotic heme transporter CydDC.
Chen ZHU ; Yanfeng SHI ; Jing YU ; Wenhao ZHAO ; Lingqiao LI ; Jingxi LIANG ; Xiaolin YANG ; Bing ZHANG ; Yao ZHAO ; Yan GAO ; Xiaobo CHEN ; Xiuna YANG ; Lu ZHANG ; Luke W GUDDAT ; Lei LIU ; Haitao YANG ; Zihe RAO ; Jun LI
Protein & Cell 2023;14(12):919-923