1
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Zou Y, Yu F, Liu X, Zu L. CH 3O Substitution Effect Revisited in the Vibrationally Resolved Laser-Induced Fluorescence Spectra of Methoxycyclohexoxy Radicals. J Phys Chem A 2024; 128:1025-1031. [PMID: 38301214 DOI: 10.1021/acs.jpca.3c07154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Abstract
The oxy-substituted alkoxy radicals have attracted wide attention due to the increasing application of oxygenated volatile organic compounds as fuel additives and solvents. Direct detection of these intermediate radicals is desired for measuring the reaction rate and investigating the oxidation mechanism of organic compounds in the atmosphere. A charge-transfer excited state induced by CH3O substitution was identified in our previous study of 3-methoxy-1-propoxy radical [Xue, J. Phys. Chem. Chem. Phys. 2021, 23, 2586]. As the C-C bonds of chain alkoxy radicals can freely rotate, further studies are needed to understand the mechanism of this long-range charge-transfer effect. In this work, vibrational-resolved laser-induced fluorescence (LIF) spectra of 3- and 4-methoxycyclohexoxy radicals were obtained under jet-cooled conditions. A large red-shift of ∼454 cm-1 of the origin band was observed when the CH3O substituent moved from the δ site to the γ site of the cyclohexoxy radical. The LIF spectra are assigned to 3-cis (e, e) and 4-trans (e, e) conformers, respectively, with the assistance of structural optimization and electron excitation studies conducted at the CAM-B3LYP/6-311++G(d,p) level of theory. Natural transition orbital analysis reveals that the intramolecular charge transfer from the C-O-C p orbital to the radical O p orbital in 3-methoxycyclohexoxy has a strong effect on the radical CO σ → O p excitation and hence results in a spectral change. On the other hand, the spectral effect of CH3O substitution almost vanishes at δ carbon. The results propose a through-bond interaction between CH3O and radical CO groups.
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Affiliation(s)
- Yizhen Zou
- College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Fengming Yu
- College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Xiaoyu Liu
- College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Lily Zu
- College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
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2
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Zhou N, Li X, Wang J, Yu H, Su C, Zu L, Huang D, Xu S. 224P Genetic landscape, PD-L1 expression, and CD8+ infiltration in Chinese pulmonary carcinoids. J Thorac Oncol 2023. [DOI: 10.1016/s1556-0864(23)00477-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2023]
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3
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Jin X, Zhou N, Zu L, He J, Yang L, Zhu Y, Sun X, Xu S. P57.14 LRMP Associates With Immune Infiltrates and Acts as a Prognostic Biomarker in Lung Adenocarcinoma. J Thorac Oncol 2021. [DOI: 10.1016/j.jtho.2021.08.586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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4
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Qin T, Xue JF, Zu L. Structural effect on electron impact decomposition of 1,3- and 1,4-cyclohexane dinitrites. CHINESE J CHEM PHYS 2021. [DOI: 10.1063/1674-0068/cjcp2102024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Tai Qin
- College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Jun-fei Xue
- College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Lily Zu
- College of Chemistry, Beijing Normal University, Beijing 100875, China
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5
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Xue J, Qin T, Zu L. Intramolecular charge transfer excitation induced by CH 3O substitution in the 3-methoxy-1-propoxy radical. Phys Chem Chem Phys 2021; 23:2586-2593. [PMID: 33474557 DOI: 10.1039/d0cp06094a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The oxy-substituted alkoxy radicals are generated from the oxidation of ethers. Their degradation path affects ozone production and the formation of the secondary organic aerosol in the atmosphere. In this work, three alkoxy radicals with methoxy (CH3O) substitution at β, γ, and δ carbon are studied using laser-induced fluorescence (LIF) spectroscopy and theoretical calculation methods. A charge transfer (CT) excited state induced by the CH3O substitution is identified to be because of the intramolecular electron transfer from the C-O-C p orbital to the radical O p orbital. Comparison of the structure and CT transition strength between GGt and TTt conformers of the 3-methoxy-1-propoxy radical (CH3OCH2CH2CH2O) suggests that this long-range charge transfer effect is mainly a through-bond interaction. The CT excited state of CH3OCH2CH2CH2O has a conical intersection with the CO σ → O p excited state, which, hence, changes the LIF spectrum of the radical. Only the decomposition product HCHO was observed in the LIF spectrum of β substituted radical CH3OCH2CH2O. For δ substituted radical CH3OCH2CH2CH2CH2O, the substitution effect on the radical stability is negligible and its LIF spectrum is close to that of unsubstituted alkoxy radicals. The results provide information for understanding the degradation chemistry of oxygenated hydrocarbon molecules in the atmosphere.
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Affiliation(s)
- Junfei Xue
- College of Chemistry, Beijing Normal University, Beijing, 100875, P. R. China.
| | - Tai Qin
- College of Chemistry, Beijing Normal University, Beijing, 100875, P. R. China.
| | - Lily Zu
- College of Chemistry, Beijing Normal University, Beijing, 100875, P. R. China.
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6
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Qin T, Xue J, Huo D, Zu L. Direct observation of the intermediate radical in the photodissociation of 1,3-cyclohexane dinitrite. Phys Chem Chem Phys 2019; 21:19359-19364. [PMID: 31455949 DOI: 10.1039/c9cp03895g] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A two-step photodissociation mechanism was proposed in the literature for dinitrites in the absence of direct evidence of the intermediate species. In this work, photodissociation dynamics of cis and trans 1,3-cyclohexane dinitrites are investigated by laser-induced fluorescence (LIF) spectroscopy and theoretical calculation methods. Observation of the fluorescence spectra of the 3-nitrosooxy cyclohexoxy radical provides direct experimental evidence that the intermediate species exists. The results indicate that photodissociation of dinitrites indeed follows a two-step mechanism, i.e. one of the O-NO bonds of the molecule breaks first upon 355 nm laser photolysis and generates an alkoxy radical (RO) plus NO; the alkoxy radical further dissociates in the secondary dissociation step and produces small fragments such as vinoxy etc.
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Affiliation(s)
- Tai Qin
- College of Chemistry, Beijing Normal University, Beijing, 100875, P. R. China.
| | - Junfei Xue
- College of Chemistry, Beijing Normal University, Beijing, 100875, P. R. China.
| | - Dayujia Huo
- College of Chemistry, Beijing Normal University, Beijing, 100875, P. R. China.
| | - Lily Zu
- College of Chemistry, Beijing Normal University, Beijing, 100875, P. R. China.
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7
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Huo D, Qin T, Zu L. Energetic switch of the proline effect in collision-induced dissociation of singly and doubly protonated peptide Ala-Ala-Arg-Pro-Ala-Ala. J Mass Spectrom 2019; 54:55-65. [PMID: 30426600 DOI: 10.1002/jms.4311] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2018] [Revised: 10/30/2018] [Accepted: 11/06/2018] [Indexed: 06/09/2023]
Abstract
Suppression of the selective cleavage at N-terminal of proline is observed in the peptide cleavage by proteolytic enzyme trypsin and in the fragment ion mass spectra of peptides containing Arg-Pro sequence. An insight into the fragmentation mechanism of the influence of arginine residue on the proline effect can help in prediction of mass spectra and in protein structure analysis. In this work, collision-induced dissociation spectra of singly and doubly charged peptide AARPAA were studied by ESI MS/MS and theoretical calculation methods. The proline effect was evaluated by comparing the experimental ratio of fragments originated from cleavage of different amide bonds. The results revealed that the backbone amide bond cleavage was selected by the energy barrier height of the fragmentation pathway although the strong proton affinity of the Arg side chain affected the stereostructure of the peptide and the dissociation mechanism. The thermodynamic stability of the fragment ions played a secondary role in the abundance ratio of fragments generated via different pathways. Fragmentation studies of protonated peptide AACitPAA supported the energy-dependent hypothesis. The results provide an explanation to the long-term arguments between the steric conflict and the proton mobility mechanisms of proline effect.
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Affiliation(s)
- Dayujia Huo
- College of Chemistry, Beijing Normal University, Beijing, China
| | - Tai Qin
- College of Chemistry, Beijing Normal University, Beijing, China
| | - Lily Zu
- College of Chemistry, Beijing Normal University, Beijing, China
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Kan XC, Wang BS, Zhang L, Zu L, Lin S, Lin JC, Tong P, Song WH, Sun YP. Critical behavior in tetragonal antiperovskite GeNFe 3 with a frustrated ferromagnetic state. Phys Chem Chem Phys 2017; 19:13703-13709. [PMID: 28497140 DOI: 10.1039/c6cp08020k] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Tetragonal GeNFe3 has a second-order ferromagnetic (FM) to paramagnetic transition at 76 K. Our integrated investigations indicate that the ground FM state is frustrated and the tetragonal symmetry is retained below 550 K based on the results of variable temperature X-ray diffraction. Critical behavior was analyzed by a systematic bulk magnetization study. The estimated critical exponents by three different methods (modified Arrott plot, the Kouvel-Fisher method, and critical isotherm analysis) conformably suggest that long-range magnetic coupling described by mean-field (MF) theoretical model is dominant in GeNFe3. The experimental M-T-H data collapse into two independent branches according to the scaling equations m = f±(h) with the renormalized magnetization m = ε-βM(H, ε) and the magnetic field h = Hε-(β+γ). The exchange distance is estimated as J(r) ∼ r-4.8 on the basis of the β and γ values, which lies between the long-range MF model (r-4.5) and the short-range 3D Heisenberg (3DH) model (r-5). Our results indicate that the competition between local magnetic moments of iron 3d electronic state and itinerant covalent interactions of N-Fe bonds should be responsible for critical behavior in this system.
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Affiliation(s)
- X C Kan
- Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, China.
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9
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Abstract
Dinitrites are effective nitrosating reagents in preparative chemistry and their decomposition products are involved in the atmospheric reaction of volatile organic compounds with nitrogen oxides (NOx). In this work, photodissociation dynamics of five alkyl dinitrites were investigated by detecting the LIF spectra of the dissociation products and theoretical calculations. The results showed that the C-C bond connecting the two nitrosooxy (-ONO) functional groups was the weakest bond in vicinal dinitrites and aldehydes were the dissociation products. For dinitrites with two ONO groups separated by a CH2 group, vinoxy and 1-methylvinoxy radicals were detected as the fragments via photodissociation, indicating a different mechanism compared to thermal decomposition. This observation demonstrated that a new reactive pathway could be initiated by photolysis of dinitrites.
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Affiliation(s)
- Lingxuan Wang
- College of Chemistry, Beijing Normal University, Beijing, 100875, P. R. China.
| | - Lily Zu
- College of Chemistry, Beijing Normal University, Beijing, 100875, P. R. China.
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10
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Zhao W, Liu Y, Zu L, Gao W. PS158 Determinants of Heart Rate Recovery for Patients With Primary PCI After ST-Elevation Myocardial Infarction. Glob Heart 2016. [DOI: 10.1016/j.gheart.2016.03.136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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11
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Zhao W, Liu Y, Zu L, Gao W. PS157 The Relationship Between Heart Rate Recovery and the Levels of Catestatin After Acute Myocardial Infarction. Glob Heart 2016. [DOI: 10.1016/j.gheart.2016.03.135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022] Open
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12
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Kan XC, Wang BS, Zu L, Lin S, Lin JC, Tong P, Song WH, Sun YP. Anomalous Hall effect in tetragonal antiperovskite GeNFe3 with a frustrated ferromagnetic state. RSC Adv 2016. [DOI: 10.1039/c6ra15976a] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
We report observed anomalous Hall effect (AHE) behavior in the antiperovskite compound GeNFe3 with a tetragonal symmetry.
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Affiliation(s)
- X. C. Kan
- Key Laboratory of Materials Physics
- Institute of Solid State Physics
- Chinese Academy of Sciences
- Hefei 230031
- China
| | - B. S. Wang
- Key Laboratory of Materials Physics
- Institute of Solid State Physics
- Chinese Academy of Sciences
- Hefei 230031
- China
| | - L. Zu
- Key Laboratory of Materials Physics
- Institute of Solid State Physics
- Chinese Academy of Sciences
- Hefei 230031
- China
| | - S. Lin
- Key Laboratory of Materials Physics
- Institute of Solid State Physics
- Chinese Academy of Sciences
- Hefei 230031
- China
| | - J. C. Lin
- Key Laboratory of Materials Physics
- Institute of Solid State Physics
- Chinese Academy of Sciences
- Hefei 230031
- China
| | - P. Tong
- Key Laboratory of Materials Physics
- Institute of Solid State Physics
- Chinese Academy of Sciences
- Hefei 230031
- China
| | - W. H. Song
- Key Laboratory of Materials Physics
- Institute of Solid State Physics
- Chinese Academy of Sciences
- Hefei 230031
- China
| | - Y. P. Sun
- Key Laboratory of Materials Physics
- Institute of Solid State Physics
- Chinese Academy of Sciences
- Hefei 230031
- China
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13
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You J, Zhang Y, Liu B, Li Y, Fang N, Zu L, Li X, Zhou Q. MicroRNA-449a inhibits cell growth in lung cancer and regulates long noncoding RNA nuclear enriched abundant transcript 1. Indian J Cancer 2015; 51 Suppl 3:e77-81. [PMID: 25818739 DOI: 10.4103/0019-509x.154055] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
OBJECTIVE Lung cancer has become the primary cause of cancer-related death now. New therapies targeting the molecular regulatory machinery were required imperatively. MicroRNAs and long noncoding RNAs can respectively or cooperatively function as oncogenes or tumor suppressor genes in human cancers. The present study identified that miR-449a was down-regulated in tissue of human lung cancer. In this study, we aimed to investigate the function of miR-449a in NL9980 and L9981 lung carcinoma cells lines and the relationship with lncRNA nuclear enriched abundant transcript 1 (NEAT1). MATERIALS AND METHODS miR-449a was profiled in several lung carcinoma cell lines by quantitative reverse transcription-polymerase chain reaction RT-PCR. We analyzed the effects of miR-449a overexpression on proliferation, apoptosis and cell cycle in L9981 cells. The regulatory relationship between miR-449a and NEAT1 was predicted in silico and further studied by miR-449a inhibitor and mimics assay. RESULTS miR-449a was expressed in four cell lines, which we selected, however miR-449a was in high level in NL9980 and in low level in L9981 (P < 0.05). When the miR-449a was the overexpression in L9981 cells, the cell growth was suppressed, and the apoptosis cells were promoted compared with the control group (P < 0.05). The G1/G0 became longer and S, G2/M became shorter (P < 0.05) by miR-449a overexpression. Further study of the interaction between miR-449a and NEAT1 show that NEAT1 was up-regulated when cells were transfected with miR-449a inhibitor, and NEAT1 was down-regulated when cells transfected with miR-449a mimics. CONCLUSIONS Our data indicate that miR-449a may function as a suppressor of lung cancer, and affects the expression of NEAT1 in lung cancer cells.
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Affiliation(s)
- J You
- Tianjin Key Labotatory of Lung Cancer Metastasis and Tumor Microenvironment, Tianjin Lung Cancer Institute, Tianjin Medical University General Hospital, Tianjin 300052, China
| | - Y Zhang
- Tianjin Key Labotatory of Lung Cancer Metastasis and Tumor Microenvironment, Tianjin Lung Cancer Institute, Tianjin Medical University General Hospital, Tianjin 300052, China
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14
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Abstract
Understanding the structure and properties of cyclohexoxy radical and its substitutes is important because of their presence in combustion processes, in atmospheric chemistry, and as intermediates in the hydrocarbon reactions. In this work, jet-cooled laser-induced fluorescence (LIF) spectra of five dimethyl substituted cyclohexoxy radicals are obtained for the first time. The correlation between the spectral variations and the radical structural changes is studied with the assistance of theoretical calculations at the B3LYP/6-31+G(d) and CASSCF/6-31+G(d) levels. The results show that the spectral characters of the dimethylcyclohexoxy radicals and their dissociation kinetics are predominantly affected by the methyl substitution position related to the C-O group. The spectral effect of the two methyl groups will add up if they locate on asymmetric carbons of the cyclohexoxy ring. Methyl substitution on β carbon weakens the six-member ring of cyclohexoxy and results in unimolecular dissociation via β C-C bond cleavage on the methyl group side and forms vinoxy variants. This study clearly shows that the LIF spectra can be used to identify cyclohexoxy and the isomers of its methyl substitutes. The results will help to understand the photochemistry of cyclic hydrocarbons in the atmospheric and combustion processes.
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Affiliation(s)
- Haiyan Hao
- College of Chemistry, Beijing Normal University, Beijing, 100875, People's Republic of China
| | - Lingxuan Wang
- College of Chemistry, Beijing Normal University, Beijing, 100875, People's Republic of China
| | - Lily Zu
- College of Chemistry, Beijing Normal University, Beijing, 100875, People's Republic of China
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15
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Xue G, Liu Z, Wang L, Zu L. The role of basic residues in the fragmentation process of the lysine rich cell-penetrating peptide TP10. J Mass Spectrom 2015; 50:220-227. [PMID: 25601696 DOI: 10.1002/jms.3524] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Revised: 09/12/2014] [Accepted: 10/07/2014] [Indexed: 06/04/2023]
Abstract
Selective cleavage effect of basic residues in the fragmentation of short peptides has been studied intensively. In contrast, the role of basic residues in the degradation of large peptides, such as cell-penetrating peptides, is largely unknown. In this work, the fragmentation of a 21 residues cell-penetrating peptide TP10 containing four lysine residues was studied by collision-induced dissociation mass spectrometry and computation methods. The influence of lysine residues on amide bond cleavage and fragmentation products was investigated. The results revealed that the selective cleavage effect of lysine residue did not present when the adjacent lysine residues in TP10 were both protonated. The localized high positive charge density might be the reason of preventing the mobile proton from migrating to the amide bonds in this part of the peptide. In contrast, the mobile proton preferred to reside in the N-terminal part of TP10 which had less positive charge. This preference gave more information of the peptide sequence in the mass spectrometry study and was helpful for stabilizing the C-terminal part of TP10, in which the basic lysine residues were preserved and crucial to the cell-penetrating process.
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Affiliation(s)
- Gaiqing Xue
- Beijing Normal University, Department of Chemistry, Beijing, 100875, China
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16
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Liu Y, Zhang S, Tan S, Yuan B, Kan X, Zu L, Sun Y. Synthesis, structure and properties of layered iron-oxychalcogenides Nd2Fe2Se2−S O3. J SOLID STATE CHEM 2015. [DOI: 10.1016/j.jssc.2014.09.038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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17
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Sun X, Mao Y, Wang J, Zu L, Hao M, Cheng G, Qu Q, Cui D, Keller ET, Chen X, Shen K, Wang J. IL-6 secreted by cancer-associated fibroblasts induces tamoxifen resistance in luminal breast cancer. Oncogene 2014:onc2014158. [PMID: 24909173 DOI: 10.1038/onc.2014.158] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 04/22/2014] [Accepted: 04/24/2014] [Indexed: 11/09/2022]
Abstract
Cancer-associated fibroblasts (CAFs) have been implicated in the development of resistance to anticancer drugs; however, the role and mechanism underlying CAFs in luminal breast cancer (BrCA) tamoxifen resistance are unclear. We found that stromal fibroblasts isolated from the central or peripheral area of BrCA have similar CAF phenotype and activity. In vitro and in vivo experiments showed that CAFs derived from clinical-luminal BrCAs induce tamoxifen resistance through decreasing estrogen receptor-α (ER-α) level when cultured with luminal BrCA cell lines MCF7 and T47D. CAFs promoted tamoxifen resistance through interleukin-6 (IL-6) secretion, which activates Janus kinase/signal transducers and activators of transcription (JAK/STAT3) and phosphatidylinositol 3-kinase (PI3K)/AKT pathways in tumor cells, followed by induction of epithelial-mesenchymal transition and upregulation of E3 ubiquitin ligase anaphase-promoting complex 10 activity, which targeted ER-α degradation through the ubiquitin-proteasome pathway. Inhibition of proteasome activity, IL-6 activity or either the JAK/STAT3 or PI3K/AKT pathways markedly reduced CAF-induced tamoxifen resistance. In xenograft experiments of CAFs mixed with MCF7 cells, CAF-specific IL-6 knockdown inhibited tumorigenesis and restored tamoxifen sensitivity. These findings indicate that CAFs mediate tamoxifen resistance through IL-6-induced degradation of ER-α in luminal BrCAs.Oncogene advance online publication, 9 June 2014; doi:10.1038/onc.2014.158.
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Affiliation(s)
- X Sun
- Department of Biochemistry and Molecular and Cell Biology, Shanghai Key Laboratory of Tumor Microenvironment and Inflammation, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Y Mao
- Comprehensive Breast Health Center, Shanghai Jiaotong University School of Medicine, Ruijin Hospital, Shanghai, China
| | - J Wang
- Department of Biochemistry and Molecular and Cell Biology, Shanghai Key Laboratory of Tumor Microenvironment and Inflammation, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - L Zu
- Department of Biochemistry and Molecular and Cell Biology, Shanghai Key Laboratory of Tumor Microenvironment and Inflammation, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - M Hao
- Department of Biochemistry and Molecular and Cell Biology, Shanghai Key Laboratory of Tumor Microenvironment and Inflammation, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - G Cheng
- Department of Biochemistry and Molecular and Cell Biology, Shanghai Key Laboratory of Tumor Microenvironment and Inflammation, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Q Qu
- Comprehensive Breast Health Center, Shanghai Jiaotong University School of Medicine, Ruijin Hospital, Shanghai, China
| | - D Cui
- Department of Urology, University of Michigan, Ann Arbor, MI, USA
| | - E T Keller
- Department of Urology, University of Michigan, Ann Arbor, MI, USA
| | - X Chen
- Comprehensive Breast Health Center, Shanghai Jiaotong University School of Medicine, Ruijin Hospital, Shanghai, China
| | - K Shen
- Comprehensive Breast Health Center, Shanghai Jiaotong University School of Medicine, Ruijin Hospital, Shanghai, China
| | - J Wang
- 1] Department of Biochemistry and Molecular and Cell Biology, Shanghai Key Laboratory of Tumor Microenvironment and Inflammation, Shanghai Jiaotong University School of Medicine, Shanghai, China [2] Comprehensive Breast Health Center, Renji Hospital, Shanghai, China
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18
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You J, Zhou Q, Fang N, Gu J, Zhang Y, Li X, Zu L. Noncoding RNA small nucleolar RNA host gene 1 promote cell proliferation in nonsmall cell lung cancer. Indian J Cancer 2014; 51 Suppl 3:e99-e102. [DOI: 10.4103/0019-509x.154092] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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19
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Abstract
Spectroscopic detection is an important method to monitor alkoxy radicals in atmospheric photochemistry studies. In this work, we report the first observation of the laser-induced fluorescence (LIF) spectra of isobutoxy, 2-methyl-1-butoxy, and 3-methyl-1-butoxy in supersonic jet-cooled condition. Ground state unimolecular decomposition and isomerization as well as excited state relaxation dynamics of isobutoxy were discussed in combination with the theoretical calculations. Analysis of the experimental and theoretical results showed that methyl substitution on the β carbon of the alkoxy radicals changed the LIF spectra of alkoxy radicals significantly. The competition between the ground state reactions and the photoexcitation process depended strongly on the radical structure and hence affected the involvement of alkoxy radicals in the photochemical reactions in the upper troposphere. This study will help to understand the dynamic role of alkoxy radicals in the atmosphere.
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Affiliation(s)
- Gaiting Liang
- College of Chemistry, Beijing Normal University , Beijing, 100875, P. R. China
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20
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Liu C, Liang G, Liu Z, Zu L. Time-Resolved Fluorescence Anisotropy Study of the Interaction Between DNA and a Peptide Truncated from the p53 Protein Core Domain. J Fluoresc 2013; 24:533-9. [DOI: 10.1007/s10895-013-1322-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2013] [Accepted: 11/07/2013] [Indexed: 11/28/2022]
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21
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Fu L, Chen T, Xue G, Zu L, Fang W. Selective cleavage enhanced by acetylating the side chain of lysine. J Mass Spectrom 2013; 48:128-134. [PMID: 23303756 DOI: 10.1002/jms.3136] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2012] [Revised: 10/24/2012] [Accepted: 10/26/2012] [Indexed: 06/01/2023]
Abstract
Selective cleavage is of great interest in mass spectrometry studies as it can help sequence identification by promoting simple fragmentation pattern of peptides and proteins. In this work, the collision-induced dissociation of peptides containing internal lysine and acetylated lysine residues were studied. The experimental and computational results revealed that multiple fragmentation pathways coexisted when the lysine residue was two amino acid residues away from N-terminal of the peptide. After acetylation of the lysine side-chain, b(n)+ ions were the most abundant primary fragment products and the Lys(Ac)-Gly amide bond became the dominant cleavage site via an oxazolone pathway. Acetylating the side-chain of lysine promoted the selective cleavage of Lys-Xxx amide bond and generated much more information of the peptide backbone sequence. The results re-evaluate the selective cleavage due to the lysine basic side-chain and provide information for studying the post-translational modification of proteins and other bio-molecules containing Lys residues.
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Chen T, Fu L, Zu L. Steady-state and time-resolved fluorescence of tetramethylrhodamine attached to DNA: correlation with DNA sequences. LUMINESCENCE 2012; 28:860-4. [DOI: 10.1002/bio.2446] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 08/30/2012] [Accepted: 09/06/2012] [Indexed: 11/06/2022]
Affiliation(s)
- Tingting Chen
- Department of Chemistry; Beijing Normal University; Beijing 100875 People's Republic of China
| | - Leixiaomeng Fu
- Department of Chemistry; Beijing Normal University; Beijing 100875 People's Republic of China
| | - Lily Zu
- Department of Chemistry; Beijing Normal University; Beijing 100875 People's Republic of China
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Affiliation(s)
- Qijun Wu
- Department of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Gaiting Liang
- Department of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Lily Zu
- Department of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Weihai Fang
- Department of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
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Wu Q, Wang L, Zu L. A LabVIEW-Based Virtual Instrument System for Laser-Induced Fluorescence Spectroscopy. J Autom Methods Manag Chem 2011; 2011:457156. [PMID: 22013388 PMCID: PMC3195440 DOI: 10.1155/2011/457156] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2011] [Accepted: 09/28/2011] [Indexed: 05/31/2023]
Abstract
We report the design and operation of a Virtual Instrument (VI) system based on LabVIEW 2009 for laser-induced fluorescence experiments. This system achieves synchronous control of equipment and acquisition of real-time fluorescence data communicating with a single computer via GPIB, USB, RS232, and parallel ports. The reported VI system can also accomplish data display, saving, and analysis, and printing the results. The VI system performs sequences of operations automatically, and this system has been successfully applied to obtain the excitation and dispersion spectra of α-methylnaphthalene. The reported VI system opens up new possibilities for researchers and increases the efficiency and precision of experiments. The design and operation of the VI system are described in detail in this paper, and the advantages that this system can provide are highlighted.
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Affiliation(s)
- Qijun Wu
- Department of Chemistry, Beijing Normal University, Beijing 100875, China
- Department of Chemistry, Bijie University, Bijie 551700, China
| | - Lufei Wang
- Department of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Lily Zu
- Department of Chemistry, Beijing Normal University, Beijing 100875, China
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Affiliation(s)
- Jiali Lin
- Department of Chemistry, Beijing Normal University, Beijing, 100875, People’s Republic of China
| | - Lily Zu
- Department of Chemistry, Beijing Normal University, Beijing, 100875, People’s Republic of China
| | - Weihai Fang
- Department of Chemistry, Beijing Normal University, Beijing, 100875, People’s Republic of China
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Peng J, Zu L, Fang W, Huang L, Wang Y, He D. Selective cleavage of protonated penetratin and its substitutes under low-energy collision-induced dissociation condition. J Mass Spectrom 2010; 45:627-634. [PMID: 20527031 DOI: 10.1002/jms.1748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
An understanding of the dissociation of penetratin is important for improving its metabolic stability and cargo-delivery efficiency. In this study, we describe the selective cleavage of the K15-K16 amide bond of penetratin under the low-energy collision-induced dissociation condition in mass spectrometry. A variety of penetratin substitutes have been studied in which key basic amino acids have been substituted within the sequence. The calculated structure indicates that an alpha-helix structure prevents the fragmentation of the central peptide domain and the side chain of lysine is involved in the proton translocation process.
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Affiliation(s)
- Juan Peng
- Department of Chemistry, Beijing Normal University, Beijing 100875, P R China
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Abstract
The dissociation of protonated peptides containing adjacent arginines has been studied by electrospray ionization-tandem mass spectrometry (ESI MS/MS) and theoretical calculations. The experimental results show that singly protonated peptides cleave at the Arg-Arg amide bond and generate the y(1) ion when adjacent arginines are the C-terminal residues. The major cleavage occurs at the C-terminal amide bond and produces the b(n-1) ion when adjacent arginines are not the C-terminal residues. The diketopiperazine and oxazolone fragmentation pathways of protonated NRR (Asn-Arg-Arg) have been investigated at the B3LYP/6-31G(d) and B3LYP/6-31++G(d,p) levels of theory. The geometries and energies of transition state species and hydrogen-bonding interaction are also discussed.
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Affiliation(s)
- Yongsheng Xiao
- Department of Chemistry, Beijing Normal University, Beijing, 100875 PR China
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Abstract
We have recorded five high resolution (200 MHz), rotationally resolved, vibrational bands of the B-X electronic transition of 2-butoxy. Two bands of the 2-butoxy spectrum have been rotationally analyzed and assigned to two different geometrical conformers of the molecule. The analyses allow the determination of the six experimental rotational constants defined by the geometry of the species in the ground (X) and excited (B) electronic states and also four spin-rotation constants for the X electronic state of the conformers. Comparison of the experimental rotational constants with the results of ab initio computations provides unambiguous conformational assignment of these bands. This approach can be extended to assign two other spectral bands to the third 2-butoxy conformer.
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Affiliation(s)
- Vadim L Stakhursky
- Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, Columbus, Ohio 43210, USA
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31
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Abstract
The laser-induced fluorescence and laser-excited dispersed fluorescence spectra of the cyclohexoxy radical has been observed under two sets of free-jet-cooling conditions, characterized by rotational temperatures of approximately 1 and 100 K. Although five conformers of cyclohexoxy are possible, it appears that all presently observed spectral bands can be accounted for by a single one. All cold spectral bands are assigned to the B-X electronic transition of the cyclohexoxy radical. Transitions to both a' and a" B state vibrational levels are observed and allowed due to a substantial pseudo-Jahn-Teller effect in the X state. Hot bands are also observed, which we attributed to transitions to the B state from the low-lying A electronic state. Analysis of the spectra yields vibrational frequencies for the X, A, and B states as well as the energy separations of their vibrationless levels.
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Affiliation(s)
- Lily Zu
- Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, Columbus, Ohio 43210, USA
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Zu L, Liu J, Gopalakrishnan S, Miller TA. The rotationally resolved electronic spectra of several conformers of 1-hexoxy and 1-heptoxy. CAN J CHEM 2004. [DOI: 10.1139/v04-056] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Laser-induced fluorescence excitation spectra of five vibronic bands of 1-hexoxy and three bands of 1-heptoxy have been recorded in a jet-cooled environment. Experimental values of rotational constants for both the [Formula: see text] and [Formula: see text] states and components of the spin-rotational tensor for the [Formula: see text] state were obtained by an analysis of the partially resolved rotational structure of the vibronic bands. Comparing these experimental results with quantum chemistry calculations, and using corresponding assignments of smaller alkoxy radicals as a guide, permitted unambiguous conformational assignments for the bands. The extension of similar assignments to larger alkoxy radicals is also discussed. Key words: electronic spectroscopy, organic radicals, combustion, atmospheric chemistry.
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Gopalakrishnan S, Zu L, Miller TA. Rotationally Resolved Electronic Spectra of the B̃−X̃ Transition in Multiple Conformers of 1-Butoxy and 1-Pentoxy Radicals. J Phys Chem A 2003. [DOI: 10.1021/jp034034f] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Sandhya Gopalakrishnan
- Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, 120 West 18th Avenue, Columbus, Ohio 43210
| | - Lily Zu
- Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, 120 West 18th Avenue, Columbus, Ohio 43210
| | - Terry A. Miller
- Laser Spectroscopy Facility, Department of Chemistry, The Ohio State University, 120 West 18th Avenue, Columbus, Ohio 43210
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Gopalakrishnan S, Carter CC, Zu L, Stakhursky V, Tarczay G, Miller TA. Rotationally resolved B̃–X̃ electronic spectra of both conformers of the 1-propoxy radical. J Chem Phys 2003. [DOI: 10.1063/1.1545441] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
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Ray PS, Sasaki H, Estrada-Hernandez T, Zu L, Maulik N. Effects of hypoxia/reoxygenation on angiogenic factors and their tyrosine kinase receptors in the rat myocardium. Antioxid Redox Signal 2001; 3:89-102. [PMID: 11291602 DOI: 10.1089/152308601750100560] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The process of angiogenesis is initiated primarily as a consequence of hypoxic stimulation at the cellular and molecular level. Although several angiogenic growth factors have been identified, at present a detailed understanding of the interplay among inducing stimuli, growth factors, and their respective molecular targets remains to be evaluated. Here we report the effects of progressively increasing durations of moderate hypoxia on the protein expression profiles and tissue distribution patterns of the vascular endothelial growth factor system and the angiopoietin/Tie system in the adult rat myocardium. The relative temporal trends of expression of the various components of these two systems, as well as apparent relationships between Flk-1 and angiopoietin-2 and between Flt-1 and Tie-1, suggest a probable sequence of involvement during myocardial angiogenesis, as proposed in our model. Such relationships may potentially be utilized in formulating strategies for sequential gene therapy to achieve clinically relevant myocardial angiogenesis.
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Affiliation(s)
- P S Ray
- Department of Surgery, University of Connecticut Health Center, Farmington, CT 06030-1110, USA
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Abstract
We describe the clinical features of a family with rippling muscle disease. Muscle stiffness and myalgia were the most prominent symptoms. Muscle rippling, although distinctive, was present in only 6 of the 11 affected family members, whereas persistent muscle contraction to muscle percussion was present in all affected adults. Although this persistent contraction resembled percussion myotonia, it was electrically silent and is therefore more aptly called "percussion contracture." We also observed two clinical features not emphasized in previously reported kindreds: mild but asymptomatic weakness of face or proximal muscles was present in 5 of 11 affected members, and 5 individuals also complained of toe walking after a prolonged period of inactivity, reflecting the disproportionate involvement of the calf muscles. The pedigree suggested autosomal dominant inheritance. Our linkage analysis excluded the region on chromosome 1q identified in a previous linkage study.
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Affiliation(s)
- Y T So
- Department of Neurology, Room A 343, Stanford University Medical Center, Stanford, California 94305-5235, USA.
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Matsuura T, Yamagata T, Burgess DL, Rasmussen A, Grewal RP, Watase K, Khajavi M, McCall AE, Davis CF, Zu L, Achari M, Pulst SM, Alonso E, Noebels JL, Nelson DL, Zoghbi HY, Ashizawa T. Large expansion of the ATTCT pentanucleotide repeat in spinocerebellar ataxia type 10. Nat Genet 2000; 26:191-4. [PMID: 11017075 DOI: 10.1038/79911] [Citation(s) in RCA: 324] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Spinocerebellar ataxia type 10 (SCA10; MIM 603516; refs 1,2) is an autosomal dominant disorder characterized by cerebellar ataxia and seizures. The gene SCA10 maps to a 3.8-cM interval on human chromosome 22q13-qter (refs 1,2). Because several other SCA subtypes show trinucleotide repeat expansions, we examined microsatellites in this region. We found an expansion of a pentanucleotide (ATTCT) repeat in intron 9 of SCA10 in all patients in five Mexican SCA10 families. There was an inverse correlation between the expansion size, up to 22.5 kb larger than the normal allele, and the age of onset (r2=0.34, P=0.018). Analysis of 562 chromosomes from unaffected individuals of various ethnic origins (including 242 chromosomes from Mexican persons) showed a range of 10 to 22 ATTCT repeats with no evidence of expansions. Our data indicate that the new SCA10 intronic ATTCT pentanucleotide repeat in SCA10 patients is unstable and represents the largest microsatellite expansion found so far in the human genome.
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Affiliation(s)
- T Matsuura
- Department of Neurology, Baylor College of Medicine, Houston, Texas, USA
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Abstract
The autosomal dominant cerebellar ataxias (ADCAs) are a clinically and genetically heterogeneous group of disorders. The clinical symptoms include cerebellar dysfunction and associated signs from dysfunction in other parts of the nervous system. So far, five spinocerebellar ataxia (SCA) genes have been identified: SCA1, SCA2, SCA3, SCA6, and SCA7. Loci for SCA4 and SCA5 have been mapped. However, approximately one-third of SCAs have remained unassigned. We have identified a Mexican American pedigree that segregates a new form of ataxia clinically characterized by gait and limb ataxia, dysarthria, and nystagmus. Two individuals have seizures. After excluding all known genetic loci for linkage, we performed a genomewide search and identified linkage to a 15-cM region on chromosome 22q13. A maximum LOD score of 4.3 (recombination fraction 0) was obtained for D22S928 and D22S1161. This distinct form of ataxia has been designated "SCA10." Anticipation was observed in the available parent-child pairs, suggesting that trinucleotide-repeat expansion may be the mutagenic mechanism.
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Affiliation(s)
- L Zu
- Division of Neurology and Rose Moss Laboratory for Parkinson's and Neurodegenerative Diseases, Burns and Allen Research Institute, Cedars-Sinai Medical Center, University of California, Los Angeles, CA 90048, USA
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Grewal RP, Tayag E, Figueroa KP, Zu L, Durazo A, Nunez C, Pulst SM. Clinical and genetic analysis of a distinct autosomal dominant spinocerebellar ataxia. Neurology 1998; 51:1423-6. [PMID: 9818872 DOI: 10.1212/wnl.51.5.1423] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To characterize a distinct form of spinocerebellar ataxia (SCA) clinically and genetically. BACKGROUND The SCAs are a genetically heterogeneous group of neurodegenerative disorders affecting the cerebellum and its connections. The mutations for SCA1, 2, 3, 6, and 7 have been identified and shown to be due to expansion of a CAG repeat in the coding region of these genes. Two additional SCA loci on chromosomes 16 and 11 have been designated SCA4 and SCA5. However, up to 20% of individuals with autosomal dominant forms of ataxias cannot be assigned any of these genotypes, implying the presence of other unidentified genes that may be involved in the development of ataxia. METHODS We ascertained and clinically characterized a six-generation pedigree segregating an autosomal dominant trait for SCA. We performed direct mutation analysis and linkage analysis for all known SCA loci. RESULTS The mutation analysis excludes SCA1, 2, 3, 6, and 7, and genetic linkage analysis excludes SCA4 and SCA5 (multipoint location scores < -2 across the candidate region). Clinical analysis of individuals in this family shows that all affected members have dysarthria, gait and limb ataxia, and nystagmus. No individuals have major brainstem or long-tract findings. Analysis of age at disease onset through multiple generations suggests anticipation. CONCLUSION This pedigree represents a genetically distinct form of SCA with a phenotype characterized by predominantly cerebellar symptoms and signs.
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Affiliation(s)
- R P Grewal
- Department of Neurology, USC School of Medicine, Los Angeles, CA, USA
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