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Li M, Ruan B, Wei J, Yang Q, Chen M, Ji M, Hou P. ACYP2 contributes to malignant progression of glioma through promoting Ca 2+ efflux and subsequently activating c-Myc and STAT3 signals. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2020; 39:106. [PMID: 32517717 PMCID: PMC7285537 DOI: 10.1186/s13046-020-01607-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 05/28/2020] [Indexed: 12/19/2022]
Abstract
Background Acylphosphatase 2 (ACYP2) is involved in cell differentiation, energy metabolism and hydrolysis of intracellular ion pump. It has been reported as a negative regulator in leukemia and a positive regulator in colon cancer, respectively. However, its biological role in glioma remains totally unclear. Methods We performed quantitative RT-PCR (qRT-PCR), immunohistochemistry (IHC) and western blot assays to evaluate ACYP2 expression. The functions of ACYP2 in glioma cells were determined by a series of in vitro and in vivo experiments, including cell proliferation, colony formation, cell cycle, apoptosis, migration, invasion and nude mouse tumorigenicity assays. In addition, western blot and co-immunoprecipitation (Co-IP) assays were used to identify its downstream targets. Results Knocking down ACYP2 in glioma cells significantly inhibited cell proliferation, colony formation, migration, invasion and tumorigenic potential in nude mice, and induced cell cycle arrest and apoptosis. Conversely, ectopic expression of ACYP2 in glioma cells dramatically promoted malignant phenotypes of glioma cells. Mechanistically, ACYP2 promoted malignant progression of glioma cells through regulating intracellular Ca2+ homeostasis via its interaction with PMCA4, thereby activating c-Myc and PTP1B/STAT3 signals. This could be effectively reversed by Ca2+ chelator BAPTA-AM or calpain inhibitor calpeptin. Conclusions Our data demonstrate that ACYP2 functions as an oncogene in glioma through activating c-Myc and STAT3 signals via the regulation of intracellular Ca2+ homeostasis, and indicate that ACYP2 may be a potential therapeutic target and prognostic biomarker in gliomas.
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Affiliation(s)
- Mengdan Li
- Key Laboratory for tumor Precision Medicine of Shaanxi Province and Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, P.R. China.,Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, P.R. China
| | - Banjun Ruan
- Key Laboratory for tumor Precision Medicine of Shaanxi Province and Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, P.R. China.,Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, P.R. China
| | - Jing Wei
- Key Laboratory for tumor Precision Medicine of Shaanxi Province and Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, P.R. China.,Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, P.R. China
| | - Qi Yang
- Key Laboratory for tumor Precision Medicine of Shaanxi Province and Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, P.R. China.,Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, P.R. China
| | - Mingwei Chen
- Department of Respiratory and Critical Care Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, P.R. China
| | - Meiju Ji
- Center for Translational Medicine, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, P.R. China.
| | - Peng Hou
- Key Laboratory for tumor Precision Medicine of Shaanxi Province and Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, P.R. China. .,Department of Endocrinology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, P.R. China.
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Jin G, Liang Y, Yan X, Zhang L, Li Z, Yin A, Wang X, Tian P. Association between the <b><i>ACYP2</i></b> Polymorphisms and IgAN Risk in the Chinese Han Population. Kidney Blood Press Res 2019; 44:810-822. [DOI: 10.1159/000501703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
<b><i>Background/Aims:</i></b> The association between <i>ACYP2</i>(Acylphosphatase 2) polymorphisms and immunoglobulin A nephropathy (IgAN) risk in the Chinese Han population remains unclear. We aimed to evaluate the association between <i>ACYP2</i> polymorphisms and IgAN risk by performing a case-control study. <b><i>Methods:</i></b> Eleven <i>ACYP2</i> single nucleotide polymorphisms (SNPs) from 416 IgAN patients and 495 healthy controls were genotyped using the Sequenom MassARRAY platform. Odds ratio (OR) and 95% confidence interval (CI) were calculated to evaluate the association of <i>ACYP2</i> polymorphisms with IgAN risk. <b><i>Results:</i></b> We observed that rs843720 was significantly associated with an increased risk of IgAN (allele G: OR = 1.23, 95% CI: 1.01–1.49, <i>p</i> = 0.036; dominant model: OR = 1.55, 95% CI: 1.01–2.37, <i>p =</i>0.044; log-additive model: OR = 1.43, 95% CI: 1.04–1.95, <i>p</i> = 0.026) before Bonferroni correction. The SNP rs12615793 was also significantly associated with an increased IgAN risk in the recessive model (OR = 3.33, 95% CI: 1.05–10.51, <i>p</i> = 0.042) before Bonferroni correction. <b><i>Conclusion:</i></b> These findings suggested that polymorphisms (rs843720 and rs12615793) of <i>ACYP2</i> may be pivotal in the development of IgAN. However, more functional and association studies with larger sample sizes should be performed to further validate our results in the future.
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Degl'Innocenti D, Ramazzotti M, Sarchielli E, Monti D, Chevanne M, Vannelli GB, Barletta E. Oxadiazon affects the expression and activity of aldehyde dehydrogenase and acylphosphatase in human striatal precursor cells: A possible role in neurotoxicity. Toxicology 2018; 411:110-121. [PMID: 30391265 DOI: 10.1016/j.tox.2018.10.021] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Revised: 10/05/2018] [Accepted: 10/30/2018] [Indexed: 12/17/2022]
Abstract
Exposure to herbicides can induce long-term chronic adverse effects such as respiratory diseases, malignancies and neurodegenerative diseases. Oxadiazon, a pre-emergence or early post-emergence herbicide, despite its low acute toxicity, may induce liver cancer and may exert adverse effects on reproductive and on endocrine functions. Unlike other herbicides, there are no indications on neurotoxicity associated with long-term exposure to oxadiazon. Therefore, we have analyzed in primary neuronal precursor cells isolated from human striatal primordium the effects of non-cytotoxic doses of oxadiazon on neuronal cell differentiation and migration, and on the expression and activity of the mitochondrial aldehyde dehydrogenase 2 (ALDH2) and of the acylphosphatase (ACYP). ALDH2 activity protects neurons against neurotoxicity induced by toxic aldehydes during oxidative stress and plays a role in neurodegenerative conditions such as Alzheimer's disease and Parkinson's disease. ACYP is involved in ion transport, cell differentiation, programmed cell death and cancer, and increased levels of ACYP have been revealed in fibroblasts from patients affected by Alzheimer's disease. In this study we demonstrated that non-cytotoxic doses of oxadiazon were able to inhibit neuronal striatal cell migration and FGF2- and BDNF-dependent differentiation towards neuronal phenotype, and to inhibit the expression and activity of ALDH2 and to increase the expression and activity of ACYP2. In addition, we have provided evidence that in human primary neuronal precursor striatal cells the inhibitory effects of oxadiazon on cell migration and differentiation towards neuronal phenotype were achieved through modulation of ACYP2. Taken together, our findings reveal for the first time that oxadiazon could exert neurotoxic effects by impairing differentiative capabilities of primary neuronal cells and indicate that ALDH2 and ACYP2 are relevant molecular targets for the neurotoxic effects of oxadiazon, suggesting a potential role of this herbicide in the onset of neurodegenerative diseases.
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Affiliation(s)
- Donatella Degl'Innocenti
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, Italy
| | - Matteo Ramazzotti
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, Italy
| | - Erica Sarchielli
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Daniela Monti
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, Italy
| | - Marta Chevanne
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, Italy
| | | | - Emanuela Barletta
- Department of Experimental and Clinical Biomedical Sciences "Mario Serio", University of Florence, Florence, Italy.
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Li J, Ma G, Zhu X, Jin T, Wang J, Li C. Association analysis of telomere length related gene ACYP2 with the gastric cancer risk in the northwest Chinese Han population. Oncotarget 2018; 8:31144-31152. [PMID: 28415712 PMCID: PMC5458196 DOI: 10.18632/oncotarget.16097] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 03/02/2017] [Indexed: 01/19/2023] Open
Abstract
Gastric cancer (GC) is a complex multifactorial disease, and genetic factors are believed the predominant cause to the occurrence of GC. We sought to investigate the associations between single nucleotide polymorphisms (SNPs) in ACYP2 gene and the risk of GC in the Northwest Chinese Han population. We recruited 302 GC cases and 300 controls from northwest China and selected 13 SNPs from ACYP2 gene. SNPs were genotyped using Sequenom Mass-ARRAY technology. Odds ratios (ORs) and 95 % confidence intervals (CIs) were used to assess the association. Bonferroni's multiple adjustment was applied to the level of significance, which was set at P < 0.00078 (0.05/65). We found that the minor alleles of rs6713088, rs11125529, rs12615793, rs843711, rs11896604, rs843706 and rs17045754 significantly stimulated the risk of GC, and homozygous alleles of above SNPs except rs6713088 were also found increasing the GC risk (P < 0.05). Under additive model and recessive model, rs11125529, rs12615793, rs843711, rs11896604, and rs17045754 also activated the risk of GC (P < 0.05). However, after Bonferroni's multiple adjusted was applied to our data, no SNP in our study was significantly related to GC risk. Further results of haplotype analysis founds that the haplotypes "TTCTAATG" (rs1682111, rs843752, rs10439478, rs843645, rs11125529, rs12615793, rs843711, and rs11896604) and "AC" (rs843706 and rs17045754) were more frequency among patients with GC, on the contrary, the haplotypes "CG" had a protective role in the GC risk (P < 0.05). Our results indicate that ACYP2 polymorphisms may influence the GC risk and may serve as a new precursory biomarker in the northwest Chinese Han population.
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Affiliation(s)
- Jianhui Li
- Department of Surgical Oncology, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi 710068, China.,The Third Affiliated Hospital, the School of Medicine Xi'an Jiaotong University, Xi'an, Shaanxi 710068, China
| | - Gang Ma
- Department of Surgical Oncology, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi 710068, China.,The Third Affiliated Hospital, the School of Medicine Xi'an Jiaotong University, Xi'an, Shaanxi 710068, China
| | - Xulong Zhu
- Department of Surgical Oncology, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi 710068, China.,The Third Affiliated Hospital, the School of Medicine Xi'an Jiaotong University, Xi'an, Shaanxi 710068, China
| | - Tianbo Jin
- Key Laboratory of Resource Biology and Biotechnology in Western China (Northwest University), Ministry of Education, College of Life Sciences, Northwest University, Xi'an, Shaanxi 710069, China.,Xi'an Tiangen Precision Medical Institute, Xi'an, Shaanxi 710075, China
| | - Jianxiong Wang
- Department of Surgical Oncology, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi 710068, China.,The Third Affiliated Hospital, the School of Medicine Xi'an Jiaotong University, Xi'an, Shaanxi 710068, China
| | - Cheng Li
- Department of Surgical Oncology, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi 710068, China.,The Third Affiliated Hospital, the School of Medicine Xi'an Jiaotong University, Xi'an, Shaanxi 710068, China
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5
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Zhang F, Zhang Y, Deng Z, Xu P, Zhang X, Jin T, Liu Q. Genetic variants in the acylphosphatase 2 gene and the risk of breast cancer in a Han Chinese population. Oncotarget 2018; 7:86704-86712. [PMID: 27894080 PMCID: PMC5349947 DOI: 10.18632/oncotarget.13495] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 10/19/2016] [Indexed: 11/25/2022] Open
Abstract
We performed a case-control study to investigate the associations between seven single nucleotide polymorphisms (SNPs) in the acylphosphatase 2 (ACYP2) gene and breast cancer (BC) risk in a Han Chinese population. There were 183 BC cases and 195 healthy controls included in the study. The SNPs were genotyped using the Sequenom MassARRAY platform. Logistic regression (adjusted for age group, body mass index [BMI], and menopause status), was used to evaluate the associations between the various genotypes and BC risk. Statistical analysis revealed that rs12621038 was associated with a decreased risk of BC in the allele (T vs. C: odds ratio [OR] = 0.71, 95% confidence interval [95% CI] = 0.52–0.94; p = 0.016), homozygous (TT vs. CC: OR = 0.47, 95% CI = 0.24–0.85; p = 0.014), dominant (OR = 0.62; 95% CI = 0.40−0.96; p = 0.032), and additive (OR = 0.68; 95% CI = 0.50–0.92; p = 0.012) models. In addition, we found that rs1682111 and rs17045754 were associated with the risk of BC and correlated with recurrence, and that rs6713088 correlated with tumor size. In sum, our findings reveal significant associations between SNPs in the ACYP2 gene and BC risk in a Han Chinese population.
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Affiliation(s)
- Fuli Zhang
- Department of Oncology Surgery, Traditional Chinese Medicine Hospital of Xi'an, Xi'an, Shaanxi 710021, China
| | - Yan Zhang
- Department of Oncology Surgery, Traditional Chinese Medicine Hospital of Xi'an, Xi'an, Shaanxi 710021, China
| | - Zhiping Deng
- Department of Breast Surgery, Tumor Hospital of Shaanxi Province, Xi'an 710061, China
| | - Pengcheng Xu
- Inner Mongolia Medical University, Hohhot 010010, Inner Mongolia, China
| | - Xiyang Zhang
- School of Life Sciences, Northwest University, Xi'an, Shaanxi 710069, China
| | - Tianbo Jin
- School of Life Sciences, Northwest University, Xi'an, Shaanxi 710069, China.,Key Laboratory of Resource Biology and Biotechnology, Ministry of Education, Northwest University, Xi'an, Shaanxi 710069, China
| | - Qiufang Liu
- Department of Radiotherapy, Tumor Hospital of Shaanxi Province, Xi'an 710061, China
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6
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Chen Z, Sun Y, Xu Z, Xu J, Li J, Yan M, Li J, Jin T, Lin H. ACYP2 polymorphisms are associated with the risk of liver cancer in a Han Chinese population. Oncotarget 2017; 8:67723-67731. [PMID: 28978066 PMCID: PMC5620206 DOI: 10.18632/oncotarget.18574] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 04/05/2017] [Indexed: 12/17/2022] Open
Abstract
We explored the association between single nucleotide polymorphisms (SNPs) in ACYP2 and liver cancer risk. Thirteen SNPs were genotyped in 473 cases and 564 controls. Genetic model, linkage disequilibrium, and haplotype analyses were performed to evaluate the association between ACPY2 SNPs and liver cancer risk. We found that rs6713088 (G allele: odds ratio [OR] = 1.27, 95% confidence interval [CI]: 1.07-1.52, P = 0.007; GG vs. CC: OR = 1.49, 95% CI: 1.02-2.1, P = 0.038), rs843711 (T allele: OR = 1.29, 95% CI: 1.09-1.54, P = 0.004; TT vs. CC: OR = 1.62, 95% CI: 1.13-2.31, P = 0.008), rs843706 (A allele: OR = 1.30, 95% CI: 1.09-1.55, P = 0.003; AA vs. CC: OR = 1.62, 95% CI: 1.13-2.31, P = 0.008), and rs843645 (GG vs. AG: OR = 1.40, 95% CI: 1.07-1.82, P = 0.014) were associated with an increased risk of liver cancer. In contrast, rs1682111 (A allele: OR = 0.77, 95% CI: 0.640-0.94, P = 0.007; AT vs. TT: OR = 0.69, 95% CI: 0.53-0.91, P = 0.007), rs843720 (additive model: OR = 0.82, 95% CI: 0.68-1.00, P = 0.049), ATATCGCC and CG haplotypes (OR = 0.76, 95% CI: 0.62-0.92, P = 0.006; OR = 0.78, 95% CI: 0.65-0.93, P = 0.006, respectively) were significantly decreased liver cancer risk. Our results confirmed that rs6713088, rs843645, rs843711 and rs843706 were significantly increased liver cancer risk, but rs1682111, rs843720 and haplotypes (ATATCGCC and CG) were significantly decreased liver cancer risk in a Han Chinese population.
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Affiliation(s)
- Zhong Chen
- Department of Thoracic Surgery, Second People's Hospital of Hainan Province, Hainan, 572200, China
| | - Yu Sun
- Department of General Surgery, Second People's Hospital of Hainan Province, Hainan, 572200, China
| | - Zhenxiong Xu
- Department of General Surgery, Second People's Hospital of Hainan Province, Hainan, 572200, China
| | - Junnv Xu
- Department of Internal Medicine-Oncology, Agricultural Reclamation General Hospital of Hainan Province, Hainan, 570311, China
| | - Jingjie Li
- Key Laboratory of Resource Biology and Biotechnology in Western China, Northwest University, Ministry of Education, School of Life Sciences, Northwest University, Shaanxi, 710069, China
| | - Mengdan Yan
- Key Laboratory of Resource Biology and Biotechnology in Western China, Northwest University, Ministry of Education, School of Life Sciences, Northwest University, Shaanxi, 710069, China
| | - Jing Li
- Key Laboratory of Resource Biology and Biotechnology in Western China, Northwest University, Ministry of Education, School of Life Sciences, Northwest University, Shaanxi, 710069, China
| | - Tianbo Jin
- Key Laboratory of Resource Biology and Biotechnology in Western China, Northwest University, Ministry of Education, School of Life Sciences, Northwest University, Shaanxi, 710069, China.,Xi'an Tiangen Precision Medical Institute, Shaanxi, 710075, China
| | - Haifeng Lin
- Department of Internal Medicine-Oncology, Agricultural Reclamation General Hospital of Hainan Province, Hainan, 570311, China
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Kim JW, Kwon OY, Kim MH. Differentially expressed genes and morphological changes during lengthened immobilization in rat soleus muscle. Differentiation 2007; 75:147-57. [PMID: 17316384 DOI: 10.1111/j.1432-0436.2006.00118.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
To examine the effect of lengthened immobilization on the expression of genes and concomitant morphological changes in soleus muscle, rat hindlimbs were immobilized at the ankle in full dorsiflexion by plaster cast. After removing the muscle (after 1 hr, 1, 4, and 7 days of immobilization), morphology and differential gene expression were analyzed through electron microscopy and differential display reverse transcription-polymerase chain reaction (DDRT-PCR), respectively. At the myotendinous junction (MTJ), a large cytoplasmic space appeared after 1 hr of immobilization and became enlarged over time, together with damaged Z lines. Interfibrillar space was detected after 1 day of immobilization, but diminished after 7 days. At the muscle belly, Z-line streaming and widening were observed following 1 hr of immobilization. Disorganization of myofilaments (misalignment of adjacent sarcomeres, distortion, or absence of Z lines) was detected after 4 days. Furthermore, mitochondrial swelling and cristae disruption were observed after 1 day of stretching. A set of 15 differentially expressed candidate genes was identified through DDRT-PCR. Of 11 known genes, seven (Atp5g3, TOM22, INrf2, Slc25a4, Hdac6, Tpm1, and Sv2b) were up and three (Podxl, Myh1, and Surf1) were down-regulated following immobilization. In the case of Acyp2, 1-day stretching-specific expression was observed. Atp5g3, Slc25a4, TOM22, and Surf1 are mitochondrial proteins related to energy metabolism, except TOM22, which has a chaperone-like activity located in the mitochondrial outer membrane. Together with these, INrf2, Hdac6, Podxl, and Acyp2 are related more or less to stress-induced apoptosis, indicating the responses to apoptotic changes in mitochondria caused by stretching. The expression of both Tpm1 and Myh1, fast twitch isoforms, suggests adaption to the immobilization. These results altogether indicate that lengthened immobilization regulates the expression of several stress/apoptosis-related and muscle-specific genes responsible for the slow-to-fast transition in soleus muscle despite profound muscle atrophy.
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Affiliation(s)
- Ji Won Kim
- Department of Physical Therapy, College of Health Science, Baekseok University, Cheonan, South Korea
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Parri M, Buricchi F, Taddei ML, Giannoni E, Raugei G, Ramponi G, Chiarugi P. EphrinA1 Repulsive Response Is Regulated by an EphA2 Tyrosine Phosphatase. J Biol Chem 2005; 280:34008-18. [PMID: 16051609 DOI: 10.1074/jbc.m502879200] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Ephrin kinases and their ephrin ligands transduce repulsion of cells in axon guidance, migration, invasiveness, and tumor growth, exerting a negative signaling on cell proliferation and adhesion. A key role of their kinase activity has been confirmed by mutant kinase inactive receptors that shift the cellular response from repulsion to adhesion. Our present study aimed to investigate the role of low molecular weight protein-tyrosine phosphatase (LMW-PTP) in ephrinA1/EphA2 signaling. LMW-PTP, by means of dephosphorylation of EphA2 kinase, negatively regulates the ephrinA1-mediated repulsive response, cell proliferation, cell adhesion and spreading, and the formation of retraction fibers, thereby confirming the relevance of the net level of tyrosine phosphorylation of Eph receptors. LMW-PTP interferes with ephrin-mediated mitogen-activated protein kinase signaling likely through inhibition of p120RasGAP binding to the activated EphA2 kinase, thereby confirming the key role of mitogen-activated protein kinase inhibition by ephrinA1 repulsive signaling. We conclude that LMW-PTP acts as a terminator of EphA2 signaling causing an efficient negative feedback loop on the biological response mediated by ephrinA1 and pointing on tyrosine phosphorylation as the main event orchestrating the repulsive response.
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Affiliation(s)
- Matteo Parri
- Department of Biochemical Sciences, University of Florence, Via le Morgagni 50, Florence 50134, Italy
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Degl'Innocenti D, Ramazzotti M, Marzocchini R, Chiti F, Raugei G, Ramponi G. Characterization of a novel Drosophila melanogaster acylphosphatase. FEBS Lett 2003; 535:171-4. [PMID: 12560098 DOI: 10.1016/s0014-5793(02)03901-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Analysis of the Drosophila melanogaster EST database led to the characterization of a novel acylphosphatase (AcPDro2). This is coded by the CG18505 (Acyp2) gene and is clearly distinct from a previously described AcPDro coded by the CG16870 (Acyp) gene from D. melanogaster. The two proteins show a 60% homology with both vertebrate isoenzymes. All the residues involved in the catalytic mechanism are conserved. AcPDro2 is a stable enzyme with a correct globular folded structure. Its activity on benzoylphosphate shows higher K(cat) but lower K(m) with respect to AcPDro. It is possible that AcPDro and AcPDro2 genes are not the direct ancestor of MT and CT vertebrate isoenzymes.
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Affiliation(s)
- Donatella Degl'Innocenti
- Dipartimento di Scienze Biochimiche, Università degli Studi di Firenze, Viale Morgagni 50, 50134 Firenze, Italy.
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Paoli P, Pazzagli L, Giannoni E, Caselli A, Manao G, Camici G, Ramponi G. A nucleophilic catalysis step is involved in the hydrolysis of aryl phosphate monoesters by human CT acylphosphatase. J Biol Chem 2003; 278:194-9. [PMID: 12409302 DOI: 10.1074/jbc.m206918200] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Acylphosphatase, one of the smallest enzymes, is expressed in all organisms. It displays hydrolytic activity on acyl phosphates, nucleoside di- and triphosphates, aryl phosphate monoesters, and polynucleotides, with acyl phosphates being the most specific substrates in vitro. The mechanism of catalysis for human acylphosphatase (the organ-common type isoenzyme) was investigated using both aryl phosphate monoesters and acyl phosphates as substrates. The enzyme is able to catalyze phosphotransfer from p-nitrophenyl phosphate to glycerol (but not from benzoyl phosphate to glycerol), as well as the inorganic phosphate-H(2)18O oxygen exchange reaction in the absence of carboxylic acids or phenols. In short, our findings point to two different catalytic pathways for aryl phosphate monoesters and acyl phosphates. In particular, in the aryl phosphate monoester hydrolysis pathway, an enzyme-phosphate covalent intermediate is formed, whereas the hydrolysis of acyl phosphates seems a more simple process in which the Michaelis complex is attacked directly by a water molecule generating the reaction products. The formation of an enzyme-phosphate covalent complex is consistent with the experiments of isotope exchange and transphosphorylation from substrates to glycerol, as well as with the measurements of the Brønsted free energy relationships using a panel of aryl phosphates with different structures. His-25 involvement in the formation of the enzyme-phosphate covalent complex during the hydrolysis of aryl phosphate monoesters finds significant confirmation in experiments performed with the H25Q mutated enzyme.
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Affiliation(s)
- Paolo Paoli
- Department of Biochemical Sciences, University of Florence, Viale Morgagni 50, 50134 Florence, Italy
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