MALDI-TOF-MS法对重组人内皮抑素蛋白分子质量测定

肿瘤的生长依赖于血管的生成,新生血管不仅为肿瘤生长提供必需的营养物质,而且为肿瘤细胞扩散提供了重要的途径[1].1997年哈佛大学的O'Reilly等[2]发现了一种内源性新血管生成抑制因子内皮抑素(Endostatin),显示出特异抑制激活的血管内皮细胞增殖和肿瘤新血管生成的生物学活性,其抗肿瘤作用具有高效、低毒、无耐药性的优点.……

Identification of differentially expressed proteins in poplar leaves in-duced by Marssonina brunnea f. sp. Multigermtubi

Black spot disease in poplar is a disease of the leaf caused by fungus. The major pathogen is Marssonina brunnea f. sp. multigermtubi. To date, little is known about the molecular mechanism of poplar （M. brunnea） interaction. In order to identify the proteins related to disease resistance and understand its molecular basis, the clone ＂NL895＂ （P. euramericana CL＂NL895＂）, which is highly resistant to M. brunnea f. sp. multigermtubi, was used in this study. We used two-dimensional gel electrophoresis （2-DE） and mass spectrometry （MS） to identify the proteins in poplar leaves that were differentially expressed in response to black spot disease pathogen, M. brunnea f. sp. multigermtubi. Proteins extracted from poplar leaves at 0, 12, 24, 48, and 72 h after pathogen-inoculation were separated by 2-DE, About 500 reproducible protein spots were detected, of which 40 protein spots displayed differential expression in levels and were subjected to Matrix assisted laser desorption/ionization time of flight mass spectrometry （MALDI-TOF MS） followed by database searching. According to the function, the identified proteins were sorted into five categories, that is, protein synthesis, metabolism, defense response and unclassified proteins.

Isolation and evaluation of antiglycation potential of polyalthic acid(furano-terpene)from Daniella oliveri

A furano-diterpene（polyalthic acid） was isolated as a major stable compound for the first time from the oleoresin of the Daniella oliveri of the family Caesalpiniacea through column chromatography fractionation.Polyalthic acid was characterized using data obtained from EIMS,HREIMS,ESI-MS,MALDI-MS as well as 1D and 2D NMR and it was evaluated for its potential to inhibit the formation of advanced glycation end-products（AGEs） using a standard in vitro antiglycation procedure.Polyalthic acid indicated a negative antiglycation potential compared to standard inhibitor that has 85%inhibition,which is an indication that polyalthic acid may not contribute to the antiglycation activity of the plant as acclaimed in folkloric medicine.The negative antiglycation observed could indicate that the polyalthic acid could trigger glycation,thereby subjecting users to various degrees of complications.The bioactivity evaluation on molinspiration evaluator indicated that polyalthic acid could be a potential drug candidate.The biological and chemical insights gained on polyalthic acid provide a good basis for future research.

Establishment and Preliminary Application of Two dimensional Electrophoresis and Mass Spectrometry in Ovary Study

Objective To apply two-dimensional electrophoresis and mass spectrometry in the ovary proteome researchMethods Protein extractions from mouse ovaries were run in IPGphor isoelectric focus system with 11 cm and 24 cm IPG strips respectively (pH 3～10, 0.3 mm thick), then the protein spots were identified by mass spectrometry.Results The ovary protein exactions separated by two-dimensional electrophoresis have got high resolution, and identifing protein by mass spectrometry was highly efficient and facilitly. These two techniques should facilitate further investigation of female reproduction proteome research.Conclusion These two rapid high resolutions and efficient techniques have a variety of applications foreground in female reproduction proteome pattern research.

α2,3-Sialylation with Fucosylation Associated with More Severe Anti-MDA5 Positive Dermatomyositis Induced by Rapidly Progressive Interstitial Lung Disease

Dermatomyositis(DM)is a heterogeneous autoimmune disease associated with numerous myositis specific antibodies(MSAs)in which DM with anti-melanoma differentiation-associated gene 5-positive(MDA5+DM)is a unique subtype of DM with higher risk of developing varying degrees of Interstitial lung disease(ILD).Glycosylation is a complex posttranslational modification of proteins associated with many autoimmune diseases.However,the association of total plasma N-glycome(TPNG)and DM,especially MDA5+DM,is still unknown.TPNG of 94 DM patients and 168 controls were analyzed by mass spectrometry with in-house reliable quantitative method called Bionic Glycome method.Logistic regression with age and sex adjusted was used to reveal the aberrant glycosylation of DM and the association of TPNG and MDA5+DM with or without rapidly progressive ILD(RPILD).The elastic net model was used to evaluate performance of glycans in distinguishing RPLID from non-RPILD,and survival analysis was analyzed with N-glycoslyation score by Kaplan-Meier survival analysis.It was found that the plasma protein N-glycome in DM showed higher fucosylation and bisection,lower sialylation(α2,3-notα2,6-linked)and galactosylation than controls.In MDA5+DM,more severe disease condition was associated with decreased sialylation(specificallyα2,3-sialylation with fucosylation)while accompanying elevated H6N5S3 and H5N4FSx,decreased galactosylation and increased fucosylation and the complexity of N-glycans.Moreover,glycosylation traits have better discrimination ability to distinguish RPILD from non-RPILD with AUC 0.922 than clinical features and is MDA5-independent.Survival advantage accrued to MDA5+DM with lower N-glycosylation score(p=3e-04).Our study reveals the aberrant glycosylation of DM for the first time and indicated that glycosylation is associated with disease severity caused by ILD in MDA5+DM,which might be considered as the potential biomarker for early diagnosis of RPILD and survival evaluation of MDA5+DM.

Comparative Analysis of the Endosperm Proteins Separated by 2-D Electrophoresis for Two Cultivars of Hybrid Rice （Oryza sativa L,）

Liangyoupeijiu is a two-parental-line, and Shanyou63 is a three-parental-line hybrid rice （Oryza sativa L.）. Although both belong to the indica subspecies, they have obvious differences with respect to morphology, physiology and grain quality. Variations in endosperm protein compositions were studied by comparing the 2-D electrophoresis （2-DE） maps for these two cultivars of hybrid rice. After matrix-assisted laser desorption/ionization time of flight mass spectrometry （MALDI-TOF/MS） analysis, a 21-kDa precursor of 19- kDa globulin was identified as the major storage protein for both cultivars. Some isoforms of peroxiredoxin and seed maturation protein were found to only exist in Shanyou63, whereas aldose reductase and starch granule-bound starch synthase were only detected in Liangyoupeijiu. These data might provide a foundation for further comparative studies of these two cultivars of hybrid rice.