1.Expression of survivin protein in prostatic carcinoma tissues and its correlation with apoptosis of cancer cells.
Wuyang GAO ; Chuanyi HU ; Muhua YI
National Journal of Andrology 2004;10(1):12-14
OBJECTIVETo investigate the expression of survivin protein in the tissues of prostatic carcinoma and its correlation with apoptosis of cancer cells.
METHODSExpression of survivin protein and apoptosis index(AI) were detected by immunohistochemical and terminal deoxynucleotidyl transterase-mediated dUTP biotin nich end labeling(TUNEL) technique in the tissues of 42 cases of prostatic carcinima (PCa) and 10 cases of normal prostate (NP).
RESULTSSurvivin prosteins were expressed in 34 of the 42 (80.59%) cases of PCa. The positive rate of survivin was strongly associated with pathological grades, clinical stages and lymphmetastasis in PCa(P < 0.05). In contrast, NP did not express survivin. Survivin protein expression was negatively correlated with AI in PCa(r = -0.679, P < 0.001).
CONCLUSIONSApoptosis inhibition by survivin may participate in the onset and progression of PCa, and the detection of survivin protein and AI in PCa may help to evaluate the degree of cell differentiation, decide therapeutic strategies and estimate prognosis.
Aged ; Apoptosis ; Humans ; Immunohistochemistry ; Inhibitor of Apoptosis Proteins ; Male ; Microtubule-Associated Proteins ; analysis ; Middle Aged ; Neoplasm Proteins ; Prostatic Neoplasms ; chemistry ; pathology
2.Structural insights into the recognition of phosphorylated FUNDC1 by LC3B in mitophagy.
Mengqi LV ; Chongyuan WANG ; Fudong LI ; Junhui PENG ; Bin WEN ; Qingguo GONG ; Yunyu SHI ; Yajun TANG
Protein & Cell 2017;8(1):25-38
Mitophagy is an essential intracellular process that eliminates dysfunctional mitochondria and maintains cellular homeostasis. Mitophagy is regulated by the post-translational modification of mitophagy receptors. Fun14 domain-containing protein 1 (FUNDC1) was reported to be a new receptor for hypoxia-induced mitophagy in mammalian cells and interact with microtubule-associated protein light chain 3 beta (LC3B) through its LC3 interaction region (LIR). Moreover, the phosphorylation modification of FUNDC1 affects its binding affinity for LC3B and regulates selective mitophagy. However, the structural basis of this regulation mechanism remains unclear. Here, we present the crystal structure of LC3B in complex with a FUNDC1 LIR peptide phosphorylated at Ser17 (pS), demonstrating the key residues of LC3B for the specific recognition of the phosphorylated or dephosphorylated FUNDC1. Intriguingly, the side chain of LC3B Lys49 shifts remarkably and forms a hydrogen bond and electrostatic interaction with the phosphate group of FUNDC1 pS. Alternatively, phosphorylated Tyr18 (pY) and Ser13 (pS) in FUNDC1 significantly obstruct their interaction with the hydrophobic pocket and Arg10 of LC3B, respectively. Structural observations are further validated by mutation and isothermal titration calorimetry (ITC) assays. Therefore, our structural and biochemical results reveal a working model for the specific recognition of FUNDC1 by LC3B and imply that the reversible phosphorylation modification of mitophagy receptors may be a switch for selective mitophagy.
Crystallography, X-Ray
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Membrane Proteins
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chemistry
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metabolism
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Microtubule-Associated Proteins
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chemistry
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metabolism
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Mitochondrial Degradation
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Mitochondrial Proteins
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chemistry
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metabolism
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Peptides
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chemistry
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metabolism
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Phosphorylation
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Protein Structure, Quaternary
3.Expression changes of tau protein and microtubule-associated proteins in testis intersitium of rats.
Zilong LIU ; Gang WANG ; Wanhong ZHANG ; Shenghong LIU ; Xiaoli WANG ; Fang WANG ; Xuejun KANG
National Journal of Andrology 2004;10(1):35-38
OBJECTIVETo examine the expression of the tau protein and microtubule-associated proteins in the testis interstitium of aged and young rats.
METHODSSprague-Dawley male rats were divided into a young group(6 months, n = 10) and an aged group(28 months, n = 10). The two steps immunohistochemistry method with the antibody against tau protein and MAP alpha was performed on the testis tissues of the rats.
RESULTSThe results showed that the immunoreactive cells of tau protein of the testis interstilial of the aged rats obviously increased(P < 0.001) than those of the young, while the immunoreactive cells of the microtubule-associated proteins decreased(P < 0.01) in the aged.
CONCLUSIONThe changes in the expression of the tau protein and microtubule-associated proteins may be related to the aging process of the testis.
Aging ; metabolism ; Animals ; Immunohistochemistry ; Male ; Microtubule-Associated Proteins ; analysis ; Rats ; Rats, Sprague-Dawley ; Testis ; chemistry ; tau Proteins ; analysis
4.Advances in the studies of sperm protein 22 (SP22).
Chuan-dan WAN ; Yu-feng HUANG ; Xiao-feng XU
National Journal of Andrology 2005;11(1):56-59
Multifunctional sperm protein 22 (SP22) is expressed ubiquitously and related to quite a few diseases. Located on the sperm surface, SP22 has an enzymatic activity that may assist sperm in penetrating into the ovum. SP22 may be carcinogenic in conspiracy with the factor ras. Among all species SP22 is highly conservative, which demonstrates its importance to life. More and more studies indicate that SP22 is directly correlated with male infertility and Parkinsons disease. This article summarizes recent researches on SP22 in the gene structure, protein structure and functional characteristics.
Animals
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Gene Components
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Humans
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Male
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Microtubule-Associated Proteins
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chemistry
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genetics
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physiology
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Protein Conformation
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Protein Deglycase DJ-1
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Rats
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Spermatozoa
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physiology
5.Caspase-3 and survivin expression in pediatric neuroblastoma and their roles in apoptosis.
Chinese Medical Journal 2004;117(12):1821-1824
BACKGROUNDNeuroblastoma, one of the common tumors in children, possesses the feature of natural regression that might be related to apoptosis caspase-3 and survivin are believed to respectively induce and inhibit apoptosis. We investigated the expression of caspase-3 and survivin in pediatric neuroblastoma and the role that these genes played in apoptosis.
METHODSThe expression of caspase-3 and survivin in pediatric neuroblastoma tissue samples was detected using in situ hybridization, ter mintuesal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL), and immunohistochemical staining. The role that these genes played in apoptosis was then evaluated.
RESULTSA converse correlation was observed between the expression of survivin and caspase-3. When survivin was expressed at high levels in neuroblastoma samples, caspase-3 expression was downregulated, and the apoptotic index decreased simultaneously.
CONCLUSIONThere is a converse correlation between the expression of caspase-3 and the expression of survivin in neuroblastoma cells, indicating that caspase-3 might induce apoptosis, and survivin may inhibit this process.
Apoptosis ; Caspase 3 ; Caspases ; analysis ; physiology ; Female ; Humans ; Immunohistochemistry ; Infant ; Infant, Newborn ; Inhibitor of Apoptosis Proteins ; Male ; Microtubule-Associated Proteins ; analysis ; physiology ; Neoplasm Proteins ; Neuroblastoma ; chemistry ; pathology
6.Changes in expression of autophagy-related proteins, Beclin-1 and LC3, and effects of rapamycin on their expression in hypoxic-ischemic hippocampus.
Rong-Hu LI ; Lun YU ; Po MIAO ; Xin DING ; Bin SUN ; Xing FENG
Chinese Journal of Contemporary Pediatrics 2015;17(4):400-404
OBJECTIVETo observe changes in the expression of autophagy-related proteins, Beclin-1 and LC3, in the hippocampal tissue of neonatal rats with hypoxic-ischemic brain damage (HIBD) at different time points, and to investigate the effect of rapamycin (Ra) on the expression of the above two proteins.
METHODSA total of 108 7-day-old Sprague-Dawley rats were randomly divided into sham, HIBD, and Ra groups (n=36 each). The HIBD model was established using the modified Rice method. For sham rats, only the left common carotid artery was separated without ligation or hypoxic treatment. For Ra-treated rats, 0.5 mg/kg Ra was administered by an intraperitoneal injection 1 hour before model establishment. The rats were anesthetized and sacrificed to collect brain tissues at 0, 6, 12, 24, 48, and 72 hours after model establishment. Changes in the expression of Beclin-1 and LC3 proteins in rat hippocampus were examined by Western blot.
RESULTSThe expression level of Beclin-1 in HIBD rats began to increase at 0 hour, peaked at 24 hours, and then declined thereafter, similar as those of Beclin-1 and LC3-II in Ra-treated rats. The expression level of LC3-II in HIBD rats began to increase at 0 hour, peaked at 12 hours, and then declined thereafter. At all time points, both Beclin-1 and LC3-II expression levels were significantly higher in HIBD and Ra-treated rats than in sham rats (P<0.05); except LC3-II at 12 hours, Beclin-1 and LC3-II expression levels were significantly higher in Ra-treated rats than in HIBD rats (P<0.05).
CONCLUSIONSHypoxia-ischemia activates autophagy in rat hippocampal cells, while Ra enhances the expression process of autophagy.
Animals ; Apoptosis Regulatory Proteins ; analysis ; Autophagy ; Beclin-1 ; Female ; Hippocampus ; chemistry ; Hypoxia-Ischemia, Brain ; metabolism ; Male ; Microtubule-Associated Proteins ; analysis ; Rats ; Rats, Sprague-Dawley ; Sirolimus ; pharmacology
7.Astragalus polysaccharide may increase sensitivity of cervical cancer HeLa cells to cisplatin by regulating cell autophagy.
Qiu-Li ZHAI ; Xiang-Dan HU ; Jing XIAO ; Dong-Qing YU
China Journal of Chinese Materia Medica 2018;43(4):805-812
This study aimed to investigate the possible sensitivity of Astragalus polysaccharides, in order to improve the chemosensitivity of cervical cancer HeLa cells to cisplatin by regulating the cell autophagy, and explore its possible mechanism. In this study, HeLa cells were divided into control group, cisplatin group, Astragalus polysaccharide group, and Astragalus polysaccharide combined with cisplatin group. MTT assay was used to detect the proliferation of cervical cancer HeLa cells. Flow cytometry was used to detect the apoptosis and cycle of HeLa cells in each experimental group. RT-PCR was used to detect the mRNA expression of autophagy-related proteins beclin1, LC3Ⅱ and p62. The expression levels of autophagy-related proteins beclin1, LC3Ⅱ, LC3Ⅰ and p62 were detected by WB method. MTT results showed that compared with the control group, the proliferation of HeLa cells was significantly inhibited in each administration group(<0.05), and the inhibitory effect of the combination group was more significant(<0.01). The apoptotic rate of HeLa cells was significantly increased(<0.05), and the apoptotic rate of the combination group was significantly increased(<0.01) compared with the control group(<0.05).In conclusion, G₀/G₁ phase showed the most significant differences between the two groups. RT-PCR and WB results showed that the gene and protein expressions of beclin1 and LC3Ⅱ were up-regulated, while the gene and protein expressions of p62 were down-regulated compared with the control group. The above-mentioned changes in the combination group were more significant. Through the analysis of the above experimental results, it is speculated that Astragalus polysaccharides may increase the sensitivity of cervical cancer HeLa cells to cisplatin by regulating the cell autophagy. Its possible mechanism of action is correlated with the up-regulation of autophagy-related proteins beclin1, the promote the conversion from LC3Ⅰ to LC3Ⅱ, the down-regulation of labeled protein p62, and the enhancement of HeLa cell autophagic activity, thereby increasing the sensitivity of HeLa cells to cisplatin chemotherapy.
Apoptosis
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Astragalus Plant
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chemistry
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Autophagy
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Cell Cycle
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Cisplatin
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pharmacology
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Drug Resistance, Neoplasm
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HeLa Cells
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Humans
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Microtubule-Associated Proteins
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metabolism
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Polysaccharides
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pharmacology
8.Expression of survivin in human gastric adenocarcinomas: correlation with proliferation and apoptosis.
Xue-quan YAO ; Fu-kun LIU ; Xiao-ping QI ; Bo WU ; Hong-lin YIN ; Heng-hui MA ; Qun-li SHI ; Xiao-jun ZHOU ; Jie-shou LI
Chinese Journal of Surgery 2004;42(3):145-148
OBJECTIVETo investigate the expression and significance of survivin, ki-67 and apoptosis index in patients with advanced gastric adenocarcinoma.
METHODSImmunohistochemical SP method for survivin expression as well as cell proliferative index (ki-67) and apoptosis index (TUNEL) was conducted on 120 gastric adenocarcinomas.
RESULTSThe survivin was detected in the cytoplasm of carcinoma cells in 59 (49.17%) of the 120 gastric adenocarcinomas, in 32 (64.00%) of the lymph node metastasis, and in 21 (17.50%) of the 120 basal layer in normal gastric mucosa, respectively. The mean proliferative index (ki-67) in primary tumors was 7.55%, which was significantly lower than the mean proliferative index of 8.34% observed in lymph node metastasis. The mean apoptosis index in primary tumors was 1.16%, which was significantly higher than the mean apoptosis index of 0.89% observed in lymph node metastasis. The frequency of survivin expression was significantly higher in lymph node metastasis than in primary gastric adenocarcinoma. Expression of survivin was significantly correlated with histological subtypes, the depth of invasion, or lymph node metastasis (P < 0.05). There was negative correlation between weighted survivin score and apoptosis index (P < 0.05), but no correlation with proliferative index.
CONCLUSIONThe high level expression of survivin might be a referenced indicator in evaluating differentiation of tumor and in predicting lymph nodes metastasis and estimating apoptosis index.
Adenocarcinoma ; metabolism ; pathology ; Aged ; Apoptosis ; Female ; Gastric Mucosa ; chemistry ; pathology ; Humans ; Immunohistochemistry ; In Situ Nick-End Labeling ; Inhibitor of Apoptosis Proteins ; Ki-67 Antigen ; analysis ; Lymph Nodes ; chemistry ; pathology ; Male ; Microtubule-Associated Proteins ; analysis ; Middle Aged ; Neoplasm Proteins ; Stomach Neoplasms ; metabolism ; pathology
9.Expression of survivin, a novel apoptosis inhibitor and cell cycle regulatory protein, in human gliomas.
Bao-Hua JIAO ; Zhi-Gang YAO ; Shao-Mei GENG ; Shu-Hao ZUO
Chinese Medical Journal 2004;117(4):612-614
Adolescent
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Adult
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Aged
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Apoptosis
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Cell Cycle
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Cell Division
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Child
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Female
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Glioma
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chemistry
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pathology
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Humans
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Immunohistochemistry
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Inhibitor of Apoptosis Proteins
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Male
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Microtubule-Associated Proteins
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analysis
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Middle Aged
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Neoplasm Proteins
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Prognosis
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Proto-Oncogene Proteins c-bcl-2
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analysis
10.New components of the necroptotic pathway.
Zhenru ZHOU ; Victor HAN ; Jiahuai HAN
Protein & Cell 2012;3(11):811-817
Programmed necrosis, also known as necroptosis, has recently drawn great attention. As an important cellular regulation mechanism, knowledge of its signaling components is expanding. Necroptosisis demonstrated to be regulated by the RIP1 and RIP3 kinases, and its pathophysiological importance has been confirmed in a number of disease models. Here we review the new members of this necroptosis pathway, MLKL, PGAM5, Drp1 and DAI, and discuss some of their possible applications according to recent findings.
Animals
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Carrier Proteins
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metabolism
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DNA-Binding Proteins
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metabolism
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GTP Phosphohydrolases
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metabolism
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Humans
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Microtubule-Associated Proteins
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metabolism
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Mitochondrial Proteins
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metabolism
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Necrosis
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Phosphoprotein Phosphatases
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Protein Kinases
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chemistry
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metabolism
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Receptor-Interacting Protein Serine-Threonine Kinases
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metabolism
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Signal Transduction
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Tumor Necrosis Factors
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metabolism