| The placenta plays a pivotal role of promoting the exchange of nutrients and waste products between the maternal and fetal circulatory systems. In addition, it is a natural barrier against numerous bacterial and viral infections during pregnancy. Maternal preeclampsia (PE) and fetal intrauterine growth restriction(IUGR) are two of the most common and serious complications of human pregnancy associated with placental abnormalities. Identification and characterization of placental multi-protein complexes is an important step to integratedly understand the protein-protein interaction networks in placenta which determine placental function. Therefore, elucidation of the placental protein interaction, the expression levels as well as post-translational modifications in various physiological and pathological conditions would provide researchers with a better understanding of the structure and function of the placentaIn this study, blue native/sodium dodecyl sulfate polyacrylamide gel electrophoresis (BN/SDS-PAGE) and Liquid chromatography-tandem mass spectrometry (LC-MS/MS) were used to screen the multi-protein complexes in placenta.733unique proteins and34known and novel heterooligomeric multi-protein complexes including mitochondrial respiratory chain complexes, integrin complexes, proteasome complexes, histone complex, and heat shock protein complexes were identified. A novel protein complex, which involves clathrin and small conductance calcium-activated potassium (SK) channel protein2, was identified and validated by antibody based gel shift assay, co-immunoprecipitation and immunouorescence staining. These results suggest that BN/SDS-PAGE, when integrated with LC-MS/MS, is a very powerful and versatile tool for the investigation of placental protein complexes.Extraction of phosphopeptides from rather complex biological samples has been a tough issue for deep and comprehensive investigation into phosphoproteomes. In this paper, we present a series of Ti-doped mesoporous silica (Ti-MPS) materials with tunable composition and controllable morphology for highly efficient enrichment of phosphopeptides. By altering the molar ratio of silicon to titanium (Si/Ti) in the precursor, the external morphology, Ti content,internal long-rang order, and surface area of Ti-MPS were all modulated accordingly with certain regularity. Tryptic digests of standard phosphoprotein α-and β-casein were employed to assess the phosphopeptide enrichment capability of Ti-MPS series. At the Si/Ti molar ratio of8:1, the optimum enrichment performance with admirable sensitivity and capacity was achieved. The detection limit for β-casein could reach10frnol, and15phosphopeptides from the digest of α-casein were resolved in the spectrum after enrichment, both superior to the behavior of commercial TiO2materials. More significantly, for the digest of human placenta mitochondria,396phosphopeptides and298phosphoproteins were definitely detected and identified after enrichment with optimized Ti-MPS material, demonstrating its remarkable applicability for untouched phosphoproteomes.In addition, this research also opened up a universal pathway to construct a composition-tunable functional material in pursuit of the maximum performance in applications.Preeclampsia is a specific disorder known to promote maternal or perinatal mortality and morbidity during pregnancy. A large amount of evidences suggest that preeclampsia could be associated with placenta, although its etiology and pathogenesis have not been extensively investigated. To better understand the molecular mechanisms involved in pathological development of placenta in preeclampsia, LC-MS/MS technologies were used to construct a large-scale comparative proteome profile of human placentas in normal and preeclamptic pregnancies. A total of2636proteins were detected in human placentas, and171different proteins were definitively identified between control and preeclamptic placentas. Further bio informatics analysis indicated that these differentially expressed proteins correlate with several specific cellular processes which occur during pathological changes of preeclamptic placenta. Several proteins were randomly selected to verify their expression patterns with Western blotting, and their cellular localizations with immunohistochemistry. Elucidation of how the changes of protein expression coordinate pathological development would provide researchers with a better understanding of these critical biological processes at an early stage of preeclamptic development, and potential therapeutic molecular targets to regulate placenta function and treat preeclampsia.To better understand the molecular mechanisms involved in pathological development of placenta in preeclampsia, high-resolution LC-MS/MS technologies were used to construct a comparative N-glycoproteomic and phosphoproteomic profiling of human placental plasma membrane in normal and preeclamptic pregnancies. A total of1027N-glyco-and2094phospho-sites were detected in human placental plasma membrane, and5N-glyco-and38phospho-proteins, respectively, with differentially expression were definitively identified between control and preeclamptic placental plasma membrane. Further bio informatics analysis indicated that these differentially expressed proteins correlate with several specific cellular processes which occur during pathological changes of preeclamptic placenta. Further bio informatics analysis indicated that these differentially expressed proteins correlate with several specific cellular processes which occur during pathological changes of preeclamptic placental plasma membrane.In summary, through proteome analysis of human placenta protein complexes and proteome from normal and preeclamptic pregnancies, we constructed the protein complexes profile, the differentially expressed protein profile and the N-glyco-and phospho-protein expression profile, and identified a number of factors potentially involved in the pathological changes of placental Further functional analyses of these proteins will be conducive to understanding the critical biological processes in placenta of PE and placental related diseases which are caused by disruption of placenta development and transition... |
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