1.Mechanism of Chaijin Jieyu Anshen Formula in regulating synaptic damage in nucleus accumbens neurons of rats with insomnia complicated with depression through TREM2/C1q axis.
Ying-Juan TANG ; Jia-Cheng DAI ; Song YANG ; Xiao-Shi YU ; Yao ZHANG ; Hai-Long SU ; Zhi-Yuan LIU ; Zi-Xuan XIANG ; Jun-Cheng LIU ; Hai-Xia HE ; Jian LIU ; Yuan-Shan HAN ; Yu-Hong WANG ; Man-Shu ZOU
China Journal of Chinese Materia Medica 2025;50(16):4538-4545
This study aims to investigate the effect of Chaijin Jieyu Anshen Formula on the neuroinflammation of rats with insomnia complicated with depression through the regulation of triggering receptor expressed on myeloid cells 2(TREM2)/complement protein C1q signaling pathway. Rats were randomly divided into a normal group, a model group, a positive drug group, as well as a high, medium, and low-dose groups of Chaijin Jieyu Anshen Formula, with 10 rats in each group. Except for the normal group, the other groups were injected with p-chlorophenylalanine and exposed to chronic unpredictable mild stress to establish the rat model of insomnia complicated with depression. The sucrose preference experiment, open field experiment, and water maze test were performed to evaluate the depression in rats. Enzyme-linked immunosorbent assay was employed to detect serum 5-hydroxytryptamine(5-HT), dopamine(DA), and norepinephrine(NE) levels. Hematoxylin and eosin staining and Nissl staining were used to observe the damage in nucleus accumbens neurons. Western blot and immunofluorescence were performed to detect TREM2, C1q, postsynaptic density 95(PSD-95), and synaptophysin 1(SYN1) expressions in rat nucleus accumbens, respectively. Golgi-Cox staining was utilized to observe the synaptic spine density of nucleus accumbens neurons. The results show that, compared with the model group, Chaijin Jieyu Anshen Formula can significantly increase the sucrose preference as well as the distance and number of voluntary activities, shorten the immobility time in forced swimming test and the successful incubation period of positioning navigation, and prolong the stay time of space exploration in the target quadrant test. The serum 5-HT, DA, and NE contents in the model group are significantly lower than those in the normal group, with the above contents significantly increased after the intervention of Chaijin Jieyu Anshen Formula. In addition, Chaijin Jieyu Anshen Formula can alleviate pathological damages such as swelling and loose arrangement of tissue cells in the nucleus accumbens, while increasing the Nissl body numbers. Chaijin Jieyu Anshen Formula can improve synaptic damage in the nucleus accumbens and increase the synaptic spine density. Compared to the normal group, the expression of C1q protein was significantly higher in the model group, while the expression of TREM2 protein was significantly lower. Compared to the model group, the intervention with Chaijin Jieyu Anshen Formula significantly downregulated the expression of C1q protein and significantly upregulated the expression of TREM2. Compared with the model group, the PSD-95 and SYN1 fluorescence intensity is significantly increased in the groups receiving different doses of Chaijin Jieyu Anshen Formula. In summary, Chaijin Jieyu Anshen Formula can reduce the C1q protein expression, relieve the TREM2 inhibition, and promote the synapse-related proteins PSD-95 and SNY1 expression. Chaijin Jieyu Anshen Formula improves synaptic injury of the nucleus accumbens neurons, thereby treating insomnia complicated with depression.
Animals
;
Male
;
Rats
;
Nucleus Accumbens/metabolism*
;
Drugs, Chinese Herbal/administration & dosage*
;
Depression/complications*
;
Membrane Glycoproteins/genetics*
;
Rats, Sprague-Dawley
;
Sleep Initiation and Maintenance Disorders/complications*
;
Neurons/metabolism*
;
Receptors, Immunologic/genetics*
;
Signal Transduction/drug effects*
;
Synapses/metabolism*
2.Effect of Acupuncture on Clinical Symptoms of Patients with Intractable Facial Paralysis: A Multicentre, Randomized, Controlled Trial.
Hong-Yu XIE ; Ze-Hua WANG ; Wen-Jing KAN ; Ai-Hong YUAN ; Jun YANG ; Min YE ; Jie SHI ; Zhen LIU ; Hong-Mei TONG ; Bi-Xiang CHA ; Bo LI ; Xu-Wen YUAN ; Chao ZHOU ; Xiao-Jun LIU
Chinese journal of integrative medicine 2025;31(9):773-781
OBJECTIVE:
To evaluate the clinical effect and safety of acupuncture manipulation on treatment of intractable facial paralysis (IFP), and verify the practicality and precision of the Anzhong Facial Paralysis Precision Scale (Eyelid Closure Grading Scale, AFPPS-ECGS).
METHODS:
A multicentre, single-blind, randomized controlled trial was conducted from October 2022 to June 2024. Eighty-nine IFP participants were randomly assigned to an ordinary acupuncture group (OAG, 45 cases) and a characteristic acupuncture group (CAG, 44 cases) using a random number table method. The main acupoints selected included Yangbai (GB 14), Quanliao (SI 18), Yingxiang (LI 20), Shuigou (GV 26), Dicang (ST 4), Chengjiang (CV 24), Taiyang (EX-HN 5), Jiache (ST 6), Fengchi (GB 20), and Hegu (LI 4). The OAG patients received ordinary acupuncture manipulation, while the CAG received characteristic acupuncture manipulation. Both groups received acupuncture treatment 3 times a week, with 10 times per course, lasting for 10 weeks. Facial recovery was assessed at baseline and after the 1st, 2nd and 3rd treatment course by AFPPS-ECGS and the House-Brackmann (H-B) Grading Scale. Infrared thermography technology was used to observe the temperature difference between healthy and affected sides in various facial regions. Adverse events and laboratory test abnormalities were recorded. The correlation between the scores of the two scales was analyzed using Pearson correlation coefficient.
RESULTS:
After the 2nd treatment course, the two groups showed statistically significant differences in AFPPS-ECGS scores (P<0.05), with even greater significance after the 3rd course (P<0.01). Similarly, H-B Grading Scale scores demonstrated significant differences between groups following the 3rd treatment course (P<0.05). Regarding temperature measurements, significant differences in temperatures of frontal and ocular areas were observed after the 2nd course (P<0.05), becoming more pronounced after the 3rd course (P<0.01). Additionally, mouth corner temperature differences reached statistical significance by the 3rd course (P<0.05). No safety-related incidents were observed during the study. Correlation analysis revealed that the AFPPS-ECGS and the H-B Grading Scale were strongly correlated (r=0.86, 0.91, 0.93, and 0.91 at baseline, and after 1st, 2nd, and 3rd treatment course, respectively, all P<0.01).
CONCLUSIONS
Acupuncture is an effective treatment for IFP, and the characteristic acupuncture manipulation enhances the therapeutic effect. The use of the AFPPS-ECGS can more accurately reflect the recovery status of patients with IFP. (Trial registration No. ChiCTR2200065442).
Humans
;
Acupuncture Therapy/methods*
;
Facial Paralysis/therapy*
;
Female
;
Male
;
Middle Aged
;
Adult
;
Treatment Outcome
;
Acupuncture Points
;
Aged
3.Targeting fibroblast growth factor receptor 1 signaling to improve bone destruction in rheumatoid arthritis
Haihui HAN ; Lei RAN ; Xiaohui MENG ; Pengfei XIN ; Zheng XIANG ; Yanqin BIAN ; Qi SHI ; Lianbo XIAO
Chinese Journal of Tissue Engineering Research 2025;29(9):1905-1912
BACKGROUND:Although researchers have noted that fibroblast growth factor receptor 1 shows great potential in rheumatoid arthritis bone destruction,there is a lack of reviews related to the potential mechanisms of fibroblast growth factor receptor 1 in rheumatoid arthritis bone destruction. OBJECTIVE:To comprehensively analyze the mechanism of fibroblast growth factor receptor 1 in bone destruction in rheumatoid arthritis by reviewing the relevant literature at both home and abroad. METHODS:We searched the CNKI database using the Chinese search terms"fibroblast growth factor receptor 1,rheumatoid arthritis,bone destruction,bone cells,osteoblasts,osteoclasts,chondrocytes,macrophages,synovial fibroblasts,T cells,vascular endothelial cells."PubMed database was searched using the English search terms"fibroblast growth factor receptor 1,rheumatoid arthritis,bone destruction,osteocytes,osteoblasts,osteoclasts,chondrocytes,macrophages,synovial fibroblasts,T cells,endothelial cells."The search period focused on April 1992 to January 2024.After screening the literature by reading titles,abstracts,and full texts,a total of 82 articles were finally included for review according to inclusion and exclusion criteria. RESULTS AND CONCLUSION:Fibroblast growth factor receptor 1 was found to be widely expressed in bone tissue-associated cells,including osteoblasts,osteoclasts,and osteoclasts.Fibroblast growth factor receptor 1 affects bone remodeling and homeostasis by regulating the function of these cells,as well as promoting the onset and progression of bone destruction in rheumatoid arthritis.Fibroblast growth factor receptor 1 is involved in the inflammatory response of synovial fibroblasts and macrophages and regulates angiogenesis of endothelial cells in synovial tissues.Fibroblast growth factor receptor 1 promotes bone destruction in several ways.Fibroblast growth factor receptor 1 may be a potential causative agent of bone destruction in rheumatoid arthritis and provides a reference for further research on its therapeutic targets.
4.Guideline for Adult Weight Management in China
Weiqing WANG ; Qin WAN ; Jianhua MA ; Guang WANG ; Yufan WANG ; Guixia WANG ; Yongquan SHI ; Tingjun YE ; Xiaoguang SHI ; Jian KUANG ; Bo FENG ; Xiuyan FENG ; Guang NING ; Yiming MU ; Hongyu KUANG ; Xiaoping XING ; Chunli PIAO ; Xingbo CHENG ; Zhifeng CHENG ; Yufang BI ; Yan BI ; Wenshan LYU ; Dalong ZHU ; Cuiyan ZHU ; Wei ZHU ; Fei HUA ; Fei XIANG ; Shuang YAN ; Zilin SUN ; Yadong SUN ; Liqin SUN ; Luying SUN ; Li YAN ; Yanbing LI ; Hong LI ; Shu LI ; Ling LI ; Yiming LI ; Chenzhong LI ; Hua YANG ; Jinkui YANG ; Ling YANG ; Ying YANG ; Tao YANG ; Xiao YANG ; Xinhua XIAO ; Dan WU ; Jinsong KUANG ; Lanjie HE ; Wei GU ; Jie SHEN ; Yongfeng SONG ; Qiao ZHANG ; Hong ZHANG ; Yuwei ZHANG ; Junqing ZHANG ; Xianfeng ZHANG ; Miao ZHANG ; Yifei ZHANG ; Yingli LU ; Hong CHEN ; Li CHEN ; Bing CHEN ; Shihong CHEN ; Guiyan CHEN ; Haibing CHEN ; Lei CHEN ; Yanyan CHEN ; Genben CHEN ; Yikun ZHOU ; Xianghai ZHOU ; Qiang ZHOU ; Jiaqiang ZHOU ; Hongting ZHENG ; Zhongyan SHAN ; Jiajun ZHAO ; Dong ZHAO ; Ji HU ; Jiang HU ; Xinguo HOU ; Bimin SHI ; Tianpei HONG ; Mingxia YUAN ; Weibo XIA ; Xuejiang GU ; Yong XU ; Shuguang PANG ; Tianshu GAO ; Zuhua GAO ; Xiaohui GUO ; Hongyi CAO ; Mingfeng CAO ; Xiaopei CAO ; Jing MA ; Bin LU ; Zhen LIANG ; Jun LIANG ; Min LONG ; Yongde PENG ; Jin LU ; Hongyun LU ; Yan LU ; Chunping ZENG ; Binhong WEN ; Xueyong LOU ; Qingbo GUAN ; Lin LIAO ; Xin LIAO ; Ping XIONG ; Yaoming XUE
Chinese Journal of Endocrinology and Metabolism 2025;41(11):891-907
Body weight abnormalities, including overweight, obesity, and underweight, have become a dual public health challenge in Chinese adults: overweight and obesity lead to a variety of chronic complications, while underweight increases the risks of malnutrition, sarcopenia, and organ dysfunction. To systematically address these issues, multidisciplinary experts in endocrinology, sports science, nutrition, and psychiatry from various regions have held multiple weight management seminars. Based on the latest epidemiological data and clinical evidence, they expanded the guideline to include assessment and intervention strategies for underweight, in addition to the core content of obesity management. This guideline outlines the etiological mechanisms, evaluation methods, and multidimensional management strategies for overweight and obesity, covering key areas such as diagnosis and assessment, medical nutrition therapy, exercise prescription, pharmacological intervention, and psychological support. It is intended to provide a scientific and standardized approach to weight management across the adult population, aiming to curb the rising prevalence of obesity, mitigate complications associated with abnormal body weight, and improve nutritional status and overall quality of life.
5.Ultrasound radiomics combined with machine learning for early diagnosis of seronegative hashimoto’s thyroiditis
Wenjun WU ; Chang LIU ; Shengsheng YAO ; Daming LIU ; Yuan LUO ; Yihan SUN ; Ting RUAN ; Mengyou LIU ; Li SHI ; Mingming XIAO ; Qi ZHANG ; Zhengshuai LIU ; Xingai JU ; Jiahao WANG ; Xiang FEI ; Li LU ; Yang GAO ; Ying ZHANG ; Liying GONG ; Xuanyu CHEN ; Wanli ZHENG ; Xiali NIU ; Xiao YANG ; Huimei CAO ; Shijie CHANG ; Zuoxin MA ; Jianchun CUI
Chinese Journal of Endocrine Surgery 2025;19(3):313-319
Objective:To evaluate the value of ultrasound radiomics combined with machine learning for early diagnosis of seronegative Hashimoto’s thyroiditis (SN-HT) .Methods:This retrospective study included 164 patients from Liaoning Provincial People’s Hospital , Lixin County People’s Hospital, Linghai Dalinghe Hospital, Fengcheng Phoenix Hospital, who underwent thyroidectomy for solitary nodules with normal thyroid function between Nov. 2016 and Jan. 2024. Postoperative pathology confirmed Hashimoto’s thyroiditis (HT) in some cases, who were further categorized into antibody-positive and antibody-negative groups based on serum antibody status. Patients without Hashimoto’s thyroiditis served as the control group. A total of 298 ultrasound images were analyzed. Radiomics features were extracted from hypoechoic non-nodular areas within 0.5 cm surrounding the tumor. Two senior pathologists and two senior ultrasound physicians independently assessed lymphocytic infiltration, eosinophilic changes of follicular epithelium, and the proportion of hypoechoic areas in pathology and ultrasound images, respectively. A machine learning model, CCH-NET, was developed using linear regression and t-distributed stochastic neighbor embedding (t-SNE) techniques. The dataset was divided into a training set (80%) and a validation set (20%) to compare the diagnostic accuracy of CCH-NET with that of senior ultrasound physicians. Results:In internal validation, CCH-NET achieved a diagnostic accuracy of 88.89% for both antibody-positive and antibody-negative groups, significantly higher than the 66.67% accuracy of senior ultrasound physicians ( P<0.01). In external validation, CCH-NET achieved 75.00% and 66.67% accuracy for the two groups, compared to 50.00% by senior ultrasound physicians. For the control group, both methods achieved 93.33% accuracy. The AUC of CCH-NET was 0.848, outperforming senior ultrasound physicians (0.681) ,demonstrating superior diagnostic performance. Conclusion:The radiomics-based CCH-NET model, using non-nodular hypoechoic areas as a specific indicator, can accurately identify early SN-HT in euthyroid patients. It significantly outperforms senior ultrasound physicians, improving diagnostic accuracy and reducing missed diagnoses.
6.Effects of epifriedelanol on gene expression of P-glycoprotein in human colorectal adenocarcinoma cell line LS174T
Jie JIANG ; Xiao-li ZHANG ; Shi-jia XIANG ; Li-hua YAO ; Guo-ping ZHONG ; Min HUANG ; Yu-hua LI
The Chinese Journal of Clinical Pharmacology 2025;41(1):50-54
Objective To investigate the effect of epifriedelanol(Epi)on gene expression of P-glycoprotein(P-gp)in human colorectal adenocarcinoma cell line LS174T and its mechanism.Methods LS174T cells were divided into control group and experimental-L,-M,-H groups.Experimental-L,-M,-H groups were treated with 5,10,20 μmol·L-1 Epi,respectively.Control group was treated with 0.1%dimethyl sulfoxide.Polymerase chain reaction was used to detect the mRNA expression level of P-gp.Theeffect of Epi on multidrug resistance protein 1(MDR1/P-gp)luciferase activity was investigated by pregnane X receptor(PXR)-MDR1/P-gp dual luciferase reporter gene assay.In addition,Western Blot was used to detect the protein expression level of P-gp and the nuclear factor-κB(NF-κB)pathway related proteins.Results The relative expression levels of P-gp mRNA in experimental-M,-H groups and control group were 52.24±5.19,23.00±3.52 and 100.00±9.00;the relative expression levels of P-gp protein were 86.37±9.96,74.85±15.92 and 100.00±12.91;the relative activities P-gp luciferase were 230.19±41.32,203.10±52.84 and 279.67±19.20;the relative expression levels of p65(RelA/p65)in nucleus were 132.36±23.93,145.96±25.15 and 100.00±10.88;the relative expression levels of phosphorylation NF-κB inhibits protein kinase α/β(p-IKKα/β)in cytoplasm were 184.00±54.82,290.10±49.59 and 100.00±15.34;the relative expression levels of phosphorylated NF-κB inhibitory protein α(p-IκBα)in cytoplasm were 125.73±18.77,133.69±20.25 and 100.00±8.12;the relative expression levels of IκBα in cytoplasm were 78.36±14.83,70.44±14.57 and 100.00±22.82,respectively.The above indexes of experimental-M and experimental-H groups were compared with control group,and the differences were statistically significant(P<0.05,P<0.01,P<0.001).Conclusion Epi can down-regulate the gene expression of P-gp in human colorectal adenocarcinoma cell line LS174T,and the mechanism may be related to activation of NF-κB and suppression of PXR.
7.Effects of epifriedelanol on gene expression of P-glycoprotein in human colorectal adenocarcinoma cell line LS174T
Jie JIANG ; Xiao-li ZHANG ; Shi-jia XIANG ; Li-hua YAO ; Guo-ping ZHONG ; Min HUANG ; Yu-hua LI
The Chinese Journal of Clinical Pharmacology 2025;41(1):50-54
Objective To investigate the effect of epifriedelanol(Epi)on gene expression of P-glycoprotein(P-gp)in human colorectal adenocarcinoma cell line LS174T and its mechanism.Methods LS174T cells were divided into control group and experimental-L,-M,-H groups.Experimental-L,-M,-H groups were treated with 5,10,20 μmol·L-1 Epi,respectively.Control group was treated with 0.1%dimethyl sulfoxide.Polymerase chain reaction was used to detect the mRNA expression level of P-gp.Theeffect of Epi on multidrug resistance protein 1(MDR1/P-gp)luciferase activity was investigated by pregnane X receptor(PXR)-MDR1/P-gp dual luciferase reporter gene assay.In addition,Western Blot was used to detect the protein expression level of P-gp and the nuclear factor-κB(NF-κB)pathway related proteins.Results The relative expression levels of P-gp mRNA in experimental-M,-H groups and control group were 52.24±5.19,23.00±3.52 and 100.00±9.00;the relative expression levels of P-gp protein were 86.37±9.96,74.85±15.92 and 100.00±12.91;the relative activities P-gp luciferase were 230.19±41.32,203.10±52.84 and 279.67±19.20;the relative expression levels of p65(RelA/p65)in nucleus were 132.36±23.93,145.96±25.15 and 100.00±10.88;the relative expression levels of phosphorylation NF-κB inhibits protein kinase α/β(p-IKKα/β)in cytoplasm were 184.00±54.82,290.10±49.59 and 100.00±15.34;the relative expression levels of phosphorylated NF-κB inhibitory protein α(p-IκBα)in cytoplasm were 125.73±18.77,133.69±20.25 and 100.00±8.12;the relative expression levels of IκBα in cytoplasm were 78.36±14.83,70.44±14.57 and 100.00±22.82,respectively.The above indexes of experimental-M and experimental-H groups were compared with control group,and the differences were statistically significant(P<0.05,P<0.01,P<0.001).Conclusion Epi can down-regulate the gene expression of P-gp in human colorectal adenocarcinoma cell line LS174T,and the mechanism may be related to activation of NF-κB and suppression of PXR.
8.Novel Structural Features of Isoflavone Synthase from Medicago truncatula Shed Light on Its Unique Enzymatic Mechanism
Chao SHI ; Zhao-Yang YE ; Fei XU ; Xiang-Ning DU ; Zhang-Xin CHEN ; Ming-Yue GU ; Jie DENG ; Wei WANG ; Liang-Yu LIU ; Mei-Ying WANG ; Xiao-Dong SU ; He-Li LIU ; Ming-Ying SHANG ; Li-Xin HUANG ; Zhen-Zhan CHANG
Chinese Journal of Biochemistry and Molecular Biology 2025;41(8):1204-1213,中插1-中插6
Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 ? by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Ⅰa-loop-helix Ⅰβ motif which cor-responds to helix Ⅰ of other P450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,the γ-domain.The structure reveals a homodimer in which the γ-domain of one molecule interacts with the β-domain of another.The plane of heme group makes an angle of ap-proximately 40° with the helix Ⅰa-loop-helix Ⅰβ motif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recogni-tion.Phe-301,Ser-303 and Gly-305 from the helix Ⅰa-loop-helix Ⅰβ motif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.
9.Colonization and transmission of carbapenem-resistant Klebsiella pneu-moniae in intensive care unit
Xiang CHEN ; Xiaodong GAO ; Chunmei ZHOU ; Shenglei HUANG ; Wenyan PAN ; Xiao LIU ; Jinghua MEI ; Qingfeng SHI
Chinese Journal of Infection Control 2025;24(1):77-84
Objective To explore and analyze the characteristics and transmission routes of carbapenem-resistant Klebsiella pneumoniae(CRKP)strains in intensive care unit(ICU).Methods From January to October 2023,17 clinical infection isolates(clinical infection group),5 active screening isolates(active screening group),and 7 envi-ronmental isolates(environmental group)of CRKP in the liver surgery ICU of a hospital were selected and analyzed by whole-genome sequencing.The differences in resistance genes,virulence genes,and sequence typing(ST)were compared,and transmission routes were analyzed based on the phylogenetic tree.Results 29 strains of CRKP car-ried 4-18 resistance genes and 52-98 virulence genes,respectively.There were no statistically significant diffe-rences in genotype distribution of resistance genes,the number of virulence genes,and gene types among three groups of CRKP(all P>0.05).ST showed that 29 CRKP strains mainly consisted of two categories:ST11 and ST15.Based on the phylogenetic tree constructed from the core genome,there were 7 highly homologous groups of CRKP,among which 4 groups had clear epidemiological associations.Conclusion CRKP in ICU carries more re-sistance and virulence genes,and some strains are highly homologous in ST and phylogenetic tree,which may lead to cross transmission.In the future,prevention and control measures should be strengthened to reduce the trans-mission of CRKP.
10.Novel Structural Features of Isoflavone Synthase from Medicago truncatula Shed Light on Its Unique Enzymatic Mechanism
Chao SHI ; Zhao-Yang YE ; Fei XU ; Xiang-Ning DU ; Zhang-Xin CHEN ; Ming-Yue GU ; Jie DENG ; Wei WANG ; Liang-Yu LIU ; Mei-Ying WANG ; Xiao-Dong SU ; He-Li LIU ; Ming-Ying SHANG ; Li-Xin HUANG ; Zhen-Zhan CHANG
Chinese Journal of Biochemistry and Molecular Biology 2025;41(8):1204-1213,中插1-中插6
Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 ? by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Ⅰa-loop-helix Ⅰβ motif which cor-responds to helix Ⅰ of other P450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,the γ-domain.The structure reveals a homodimer in which the γ-domain of one molecule interacts with the β-domain of another.The plane of heme group makes an angle of ap-proximately 40° with the helix Ⅰa-loop-helix Ⅰβ motif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recogni-tion.Phe-301,Ser-303 and Gly-305 from the helix Ⅰa-loop-helix Ⅰβ motif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.

Result Analysis
Print
Save
E-mail