The sequence upstream of the antibody variable region(antibody upstream sequence[AUS])consists of a 5′untranslated region(5′UTR)and a preceding leader region.The sequence variations in AUS affect antibody engineerin...The sequence upstream of the antibody variable region(antibody upstream sequence[AUS])consists of a 5′untranslated region(5′UTR)and a preceding leader region.The sequence variations in AUS affect antibody engineering and PCR based antibody quantification and may also be implicated in mRNA transcription and translation.However,the diversity of AUSs remains elusive.Using 5′rapid amplification of cDNA ends and high-throughput antibody repertoire sequencing technique,we acquired full-length AUSs for human,rhesus macaque,cynomolgus macaque,mouse,and rat.We designed a bioinformatics pipeline and identified 3307 unique AUSs,corresponding to 3026 and 1457 unique sequences for 5′UTR and leader region,respectively.Comparative analysis indicated that 928(63.69%)leader sequences are novel relative to those recorded in the international ImMunoGeneTics information system.Evolutionarily,leader sequences are more conserved than 5′UTR and seem to coevolve with their downstream V genes.Besides,single-nucleotide polymorphisms are position dependent for leader regions and may contribute to the functional reversal of the downstream V genes.Finally,the AUGs in AUSs were found to have little impact on gene expression.Taken together,our findings can facilitate primer design for capturing antibodies efficiently and provide a valuable resource for antibody engineering and molecule-level antibody studies.展开更多
Objective: Based on a partialsubtilisin-like protease, Prl genomic sequence ofPythium guiyangense which has been cloned before, Panhandle PCR strategy was used to amplify the upstream flanking sequence adjacent to th...Objective: Based on a partialsubtilisin-like protease, Prl genomic sequence ofPythium guiyangense which has been cloned before, Panhandle PCR strategy was used to amplify the upstream flanking sequence adjacent to the known sequence of the Prl gene. Methods: The genomic DNA was firstly digested with BamH I and then treated with calf intestinal alkaline phosphatase(CIAP). Next, a 5' phosphorylated oligonucleotide was ligated to the 5' ends of BamH I -digested DNA. After denaturation, intmstrand annealing and polymemse extension, a pan with a handle was formed,and lastly the nested PCR was performed. Results: A 864 bp product was amplified,which was adjacent to the known sequence of Prl gene.The gene has been accessed by GenBank (Accession:JQ975036). Conclusion: Panhandle PCR is a quick and convenient approach for amplifying and identifying unknown partner genes,which facilitates cloning full-length Prl gene展开更多
The genes encoding DNA-binding domain(BD) designed based on the yeast transcriptional activator GAL4 and protein transduction domain of HIV-1 Tat protein were fused via soft linker peptide sequence, and cloned into ...The genes encoding DNA-binding domain(BD) designed based on the yeast transcriptional activator GAL4 and protein transduction domain of HIV-1 Tat protein were fused via soft linker peptide sequence, and cloned into yeast expression vector pPIC9k. The resulted plasmid pTG was linearized and transfected into Pichia pastoris strains GS 115 by electroporation. High copies of transformants were obtained with Muts and HIS+ phenotype identi- fication, PCR amplification and screening of G418. After flask culture and expression induced by methanol, the target protein named TG was well expressed and analyzed by SDS-PAGE and Western blot. Under optimized conditions, the yield of soluble recombinant protein was approximately 39.7 mg/L. DNA binding activity and cell transduction property of TG were analyzed by gel eleetrophoresis and fluorescent microscopy. The results show that the recombinant protein could bind strongly to the plasmid containing upstream activating sequence(UAS). The cell experiments revealed that TG could deliver the binding plasmid into HEK-293 cells effectively. In summary, the work presented here suggests that TG is specific toward UAS containing plasmid and has the potential for use as nonviral DNA delivery agent.展开更多
Bio-manufacturing via microbial cell factory requires large promoter library for fine-tuned metabolic engi-neering.Ogataea polymorpha,one of the methylotrophic yeasts,possesses advantages in broad substrate spec-trum,...Bio-manufacturing via microbial cell factory requires large promoter library for fine-tuned metabolic engi-neering.Ogataea polymorpha,one of the methylotrophic yeasts,possesses advantages in broad substrate spec-trum,thermal-tolerance,and capacity to achieve high-density fermentation.However,a limited number of available promoters hinders the engineering of O.polymorpha for bio-productions.Here,we systematically characterized native promoters in O.polymorpha by both GFP fluorescence and fatty alcohol biosynthesis.Ten constitutive promoters(P_(PDH),P_(PYK),P_(FBA),P_(PGM),P_(GLK),P_(TRI),P(GPI),P_(ADH1),P_(TEF1) and P_(GCW14))were obtained with the activity range of 13%–130% of the common promoter P_(GAP)(the promoter of glyceraldehyde-3-phosphate de-hydrogenase),among which P_(PDH) and P_(GCW14) were further verified by biosynthesis of fatty alcohol.Furthermore,the inducible promoters,including ethanol-induced P_(ICL1),rhamnose-induced P_(LRA3) and P_( LRA4),and a bidirectional promoter(P_(Mal)-P_(Per))that is strongly induced by sucrose,further expanded the promoter toolbox in O.polymorpha.Finally,a series of hybrid promoters were constructed via engineering upstream activation sequence(UAS),which increased the activity of native promoter P LRA3 by 4.7–10.4 times without obvious leakage expression.Therefore,this study provided a group of constitutive,inducible,and hybrid promoters for metabolic engineering of O.polymorpha,and also a feasible strategy for rationally regulating the promoter strength.展开更多
基金supported by the National Natural Science Foundation of China(NSFC)(31771479 to Z.Z.)NSFC Projects of International Cooperation and Exchanges of NSFC(61661146004 to Z.Z.)+1 种基金the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(2017BT01S131 to Z.Z.)Guangdong-Hong Kong-Macao-Joint Labs Program from Guangdong Science and Technology(2019B121205005 to X.Y.)。
文摘The sequence upstream of the antibody variable region(antibody upstream sequence[AUS])consists of a 5′untranslated region(5′UTR)and a preceding leader region.The sequence variations in AUS affect antibody engineering and PCR based antibody quantification and may also be implicated in mRNA transcription and translation.However,the diversity of AUSs remains elusive.Using 5′rapid amplification of cDNA ends and high-throughput antibody repertoire sequencing technique,we acquired full-length AUSs for human,rhesus macaque,cynomolgus macaque,mouse,and rat.We designed a bioinformatics pipeline and identified 3307 unique AUSs,corresponding to 3026 and 1457 unique sequences for 5′UTR and leader region,respectively.Comparative analysis indicated that 928(63.69%)leader sequences are novel relative to those recorded in the international ImMunoGeneTics information system.Evolutionarily,leader sequences are more conserved than 5′UTR and seem to coevolve with their downstream V genes.Besides,single-nucleotide polymorphisms are position dependent for leader regions and may contribute to the functional reversal of the downstream V genes.Finally,the AUGs in AUSs were found to have little impact on gene expression.Taken together,our findings can facilitate primer design for capturing antibodies efficiently and provide a valuable resource for antibody engineering and molecule-level antibody studies.
基金Supported by the Guangxi Department of education scientific research funds,China(No.200103YB154)
文摘Objective: Based on a partialsubtilisin-like protease, Prl genomic sequence ofPythium guiyangense which has been cloned before, Panhandle PCR strategy was used to amplify the upstream flanking sequence adjacent to the known sequence of the Prl gene. Methods: The genomic DNA was firstly digested with BamH I and then treated with calf intestinal alkaline phosphatase(CIAP). Next, a 5' phosphorylated oligonucleotide was ligated to the 5' ends of BamH I -digested DNA. After denaturation, intmstrand annealing and polymemse extension, a pan with a handle was formed,and lastly the nested PCR was performed. Results: A 864 bp product was amplified,which was adjacent to the known sequence of Prl gene.The gene has been accessed by GenBank (Accession:JQ975036). Conclusion: Panhandle PCR is a quick and convenient approach for amplifying and identifying unknown partner genes,which facilitates cloning full-length Prl gene
基金Supported by National High-tech Research and Development Program of China(No.2007AA021004)
文摘The genes encoding DNA-binding domain(BD) designed based on the yeast transcriptional activator GAL4 and protein transduction domain of HIV-1 Tat protein were fused via soft linker peptide sequence, and cloned into yeast expression vector pPIC9k. The resulted plasmid pTG was linearized and transfected into Pichia pastoris strains GS 115 by electroporation. High copies of transformants were obtained with Muts and HIS+ phenotype identi- fication, PCR amplification and screening of G418. After flask culture and expression induced by methanol, the target protein named TG was well expressed and analyzed by SDS-PAGE and Western blot. Under optimized conditions, the yield of soluble recombinant protein was approximately 39.7 mg/L. DNA binding activity and cell transduction property of TG were analyzed by gel eleetrophoresis and fluorescent microscopy. The results show that the recombinant protein could bind strongly to the plasmid containing upstream activating sequence(UAS). The cell experiments revealed that TG could deliver the binding plasmid into HEK-293 cells effectively. In summary, the work presented here suggests that TG is specific toward UAS containing plasmid and has the potential for use as nonviral DNA delivery agent.
基金National Natural Science Foundation of China(21808216,22161142008 and M-0246)Key project at central government level:The ability establishment of sustainable use for valuable Chinese medicine resources(2060302)DICP innovation grant(DICP I202021 and I201920)from Dalian Institute of Chemicals Physics,CAS.
文摘Bio-manufacturing via microbial cell factory requires large promoter library for fine-tuned metabolic engi-neering.Ogataea polymorpha,one of the methylotrophic yeasts,possesses advantages in broad substrate spec-trum,thermal-tolerance,and capacity to achieve high-density fermentation.However,a limited number of available promoters hinders the engineering of O.polymorpha for bio-productions.Here,we systematically characterized native promoters in O.polymorpha by both GFP fluorescence and fatty alcohol biosynthesis.Ten constitutive promoters(P_(PDH),P_(PYK),P_(FBA),P_(PGM),P_(GLK),P_(TRI),P(GPI),P_(ADH1),P_(TEF1) and P_(GCW14))were obtained with the activity range of 13%–130% of the common promoter P_(GAP)(the promoter of glyceraldehyde-3-phosphate de-hydrogenase),among which P_(PDH) and P_(GCW14) were further verified by biosynthesis of fatty alcohol.Furthermore,the inducible promoters,including ethanol-induced P_(ICL1),rhamnose-induced P_(LRA3) and P_( LRA4),and a bidirectional promoter(P_(Mal)-P_(Per))that is strongly induced by sucrose,further expanded the promoter toolbox in O.polymorpha.Finally,a series of hybrid promoters were constructed via engineering upstream activation sequence(UAS),which increased the activity of native promoter P LRA3 by 4.7–10.4 times without obvious leakage expression.Therefore,this study provided a group of constitutive,inducible,and hybrid promoters for metabolic engineering of O.polymorpha,and also a feasible strategy for rationally regulating the promoter strength.