Background Parkinson’s disease(PD)and multiple system atrophy(MSA)are classified asα-synucleinopathies and are primarily differentiated by their clinical phenotypes.Delineating these diseases based on their specific...Background Parkinson’s disease(PD)and multiple system atrophy(MSA)are classified asα-synucleinopathies and are primarily differentiated by their clinical phenotypes.Delineating these diseases based on their specificα-synuclein(α-Syn)proteoform pathologies is crucial for accurate antemortem biomarker diagnosis.Newly identifiedα-Syn pathologies in PD raise questions about whether MSA exhibits a similar diversity.This prompted the need for a comparative study focusing onα-Syn epitope-specific immunoreactivities in both diseases,which could clarify the extent of pathological overlap and diversity,and guide more accurate biomarker development.Methods We utilised a multiplex immunohistochemical approach to detect multiple structural domains ofα-Syn proteoforms across multiple regions prone to pathological accumulation in MSA(n=10)and PD(n=10).Comparison of epitope-specificα-Syn proteoforms was performed in the MSA medulla,inferior olivary nucleus,substantia nigra,hippocampus,and cerebellum,and in the PD olfactory bulb,medulla,substantia nigra,hippocampus,and entorhinal cortex.Results N-terminus and C-terminus antibodies detected significantly moreα-Syn pathology in MSA than antibodies for phosphorylated(pS129)α-Syn,which are classically used to detectα-Syn.Importantly,C-terminus immunolabelling is more pronounced in MSA compared to PD.Meanwhile,N-terminus immunolabelling consistently detected the highest percentage ofα-Syn across pathologically burdened regions of both diseases,which could be of biological significance.As expected,oligodendroglial involvement distinguished MSA from PD,but in contrast to PD,no substantial astrocytic or microglialα-Syn accumulation in MSA occurred.These data confirm glial-specific changes between these diseases when immunolabelling the N-terminus epitope.In comparison,N-terminus neuronalα-Syn was present in PD and MSA,with most MSA neurons lacking pS129α-Syn proteoforms.This explains why characterisation of neuronal MSA pathologies is lacking and challenges the reliance on pS129 antibodies for the accurate quantification ofα-Syn pathological load acrossα-synucleinopathies.Conclusions These findings underscore the necessity of utilising a multiplex approach to detectα-Syn,most importantly including the N-terminus,to capture the entire spectrum ofα-Syn proteoforms inα-synucleinopathies.The data provide novel insights toward the biological differentiation of theseα-synucleinopathies and pave the way for more refined antemortem diagnostic methods to facilitate early identification and intervention of these neurodegenerative diseases.展开更多
A new pyridoxal-5-phosphate （PLP） derivative FHMDP was developed for the transamination of different pep- tides with three most hindered amino acid residues （Leu, Ile, Val） as their N-terminus. Compared to the pre...A new pyridoxal-5-phosphate （PLP） derivative FHMDP was developed for the transamination of different pep- tides with three most hindered amino acid residues （Leu, Ile, Val） as their N-terminus. Compared to the previously reported reactions of PLP derivatives, the N-terminus transamination could be accomplished efficiently with the new compound.展开更多
1,4-α-Glucan branching enzyme(GBE;EC 2.4.1.18),which plays an important role in starch modification,has been mostly expressed in Escherichia coli.The application of GBE in food industry is limited by the low yield of...1,4-α-Glucan branching enzyme(GBE;EC 2.4.1.18),which plays an important role in starch modification,has been mostly expressed in Escherichia coli.The application of GBE in food industry is limited by the low yield of enzyme and production of endotoxins in E.coli.In this study,we first found that GBE from Geobacillus thermoglucosidans STB02(Gt-GBE)could be highly expressed in the Bacillus subtilis which is a food grade strain.The pathway of secretion was non-classical independent of signal peptides and was related to cell lysis.Bioinformatics analysis combined with site-directed mutagenesis was used to explore the influence of the N-terminal structure on its secretion.We found that the extracellular activity of Gt-GBE was increased about 17.29%and the secretion rate was also greatly improved through truncating the loop structure at the N-terminus.Besides,it was found that there was an optimal hydrophobicity,which increased the extracellular activity of Gt-GBE by 12.90%through the substitution of N-terminal amino acids with hydrophobic residues.In summary,we achieved high-efficiency non-classical secretion of Gt-GBE in B.subtilis and found an important role of the N-terminus in this secretion pathway,which provides a new perspective for improving the expression of proteins in B.subtilis.展开更多
We have developed a facile N-terminus helix-nucleating strategy using an unnaturally tethered aspartic acid(TD strategy). Relatively weak nuclear translocation efficiency of TD PERM limits its further biological appli...We have developed a facile N-terminus helix-nucleating strategy using an unnaturally tethered aspartic acid(TD strategy). Relatively weak nuclear translocation efficiency of TD PERM limits its further biological applications. A potent peptide inhibitor of estrogen receptor α(ER-α) with significantly increased cellular uptake and cellular distribution was developed by cell penetrating peptide attachment.The resulted peptide conjugate showed selective toxicity towards estrogen receptor positive cell lines and induced decreased transcription of estrogen receptor a downstream genes.展开更多
文摘Background Parkinson’s disease(PD)and multiple system atrophy(MSA)are classified asα-synucleinopathies and are primarily differentiated by their clinical phenotypes.Delineating these diseases based on their specificα-synuclein(α-Syn)proteoform pathologies is crucial for accurate antemortem biomarker diagnosis.Newly identifiedα-Syn pathologies in PD raise questions about whether MSA exhibits a similar diversity.This prompted the need for a comparative study focusing onα-Syn epitope-specific immunoreactivities in both diseases,which could clarify the extent of pathological overlap and diversity,and guide more accurate biomarker development.Methods We utilised a multiplex immunohistochemical approach to detect multiple structural domains ofα-Syn proteoforms across multiple regions prone to pathological accumulation in MSA(n=10)and PD(n=10).Comparison of epitope-specificα-Syn proteoforms was performed in the MSA medulla,inferior olivary nucleus,substantia nigra,hippocampus,and cerebellum,and in the PD olfactory bulb,medulla,substantia nigra,hippocampus,and entorhinal cortex.Results N-terminus and C-terminus antibodies detected significantly moreα-Syn pathology in MSA than antibodies for phosphorylated(pS129)α-Syn,which are classically used to detectα-Syn.Importantly,C-terminus immunolabelling is more pronounced in MSA compared to PD.Meanwhile,N-terminus immunolabelling consistently detected the highest percentage ofα-Syn across pathologically burdened regions of both diseases,which could be of biological significance.As expected,oligodendroglial involvement distinguished MSA from PD,but in contrast to PD,no substantial astrocytic or microglialα-Syn accumulation in MSA occurred.These data confirm glial-specific changes between these diseases when immunolabelling the N-terminus epitope.In comparison,N-terminus neuronalα-Syn was present in PD and MSA,with most MSA neurons lacking pS129α-Syn proteoforms.This explains why characterisation of neuronal MSA pathologies is lacking and challenges the reliance on pS129 antibodies for the accurate quantification ofα-Syn pathological load acrossα-synucleinopathies.Conclusions These findings underscore the necessity of utilising a multiplex approach to detectα-Syn,most importantly including the N-terminus,to capture the entire spectrum ofα-Syn proteoforms inα-synucleinopathies.The data provide novel insights toward the biological differentiation of theseα-synucleinopathies and pave the way for more refined antemortem diagnostic methods to facilitate early identification and intervention of these neurodegenerative diseases.
基金Project supported by the National Natural Science Foundation of China （Nos. 20932006 and 21002056）.
文摘A new pyridoxal-5-phosphate （PLP） derivative FHMDP was developed for the transamination of different pep- tides with three most hindered amino acid residues （Leu, Ile, Val） as their N-terminus. Compared to the previously reported reactions of PLP derivatives, the N-terminus transamination could be accomplished efficiently with the new compound.
基金This work was financially supported by National Key R&D Program of China(2021YFD2101001-2)the National Natural Science Foundation of China(No.31901628)+1 种基金the Fundamental Research Funds for the Central Universities(JUSRP121004)Science and Technology Support Program(Modern Agriculture)of Jiangsu Province(BE2022323).
文摘1,4-α-Glucan branching enzyme(GBE;EC 2.4.1.18),which plays an important role in starch modification,has been mostly expressed in Escherichia coli.The application of GBE in food industry is limited by the low yield of enzyme and production of endotoxins in E.coli.In this study,we first found that GBE from Geobacillus thermoglucosidans STB02(Gt-GBE)could be highly expressed in the Bacillus subtilis which is a food grade strain.The pathway of secretion was non-classical independent of signal peptides and was related to cell lysis.Bioinformatics analysis combined with site-directed mutagenesis was used to explore the influence of the N-terminal structure on its secretion.We found that the extracellular activity of Gt-GBE was increased about 17.29%and the secretion rate was also greatly improved through truncating the loop structure at the N-terminus.Besides,it was found that there was an optimal hydrophobicity,which increased the extracellular activity of Gt-GBE by 12.90%through the substitution of N-terminal amino acids with hydrophobic residues.In summary,we achieved high-efficiency non-classical secretion of Gt-GBE in B.subtilis and found an important role of the N-terminus in this secretion pathway,which provides a new perspective for improving the expression of proteins in B.subtilis.
基金financial support from the National Natural Science Foundation of China (Nos. 21778009 and 81701818 MOST2015DFA31590)the Shenzhen Science and Technology Innovation Committee (Nos. JCYJ20170412150719814 and GJHS20170310093122365)
文摘We have developed a facile N-terminus helix-nucleating strategy using an unnaturally tethered aspartic acid(TD strategy). Relatively weak nuclear translocation efficiency of TD PERM limits its further biological applications. A potent peptide inhibitor of estrogen receptor α(ER-α) with significantly increased cellular uptake and cellular distribution was developed by cell penetrating peptide attachment.The resulted peptide conjugate showed selective toxicity towards estrogen receptor positive cell lines and induced decreased transcription of estrogen receptor a downstream genes.
