Construction and self-activation detection of yeast two-hybrid bait plasmid of human programmed cell death ligand 1 immunoglobulin variable region domain gene / 中国生物制品学杂志

@#Objective To construct a yeast two-hybrid recombinant bait plasmid of human programmed cell death ligand 1(PD-L1)immunoglobulin variable region(IgV)domain gene,detect its expression in yeast and detect the cytotoxicity and self-activation of PD-L1 IgV protein as well as the interaction between PD-L1 IgV and human thioredoxin(hTrx).Methods Human PD-L1 was analyzed by bioinformatics method,and primers were designed to amplify PD-L1 IgV domain based on the coding region of PD-L1 gene registered in NCBI GenBank database. PCR amplification was carried out with pENTERPD-L1 plasmid as template,and then cloned into yeast two-hybrid bait vector pGBKT7. The recombinant bait plasmid and pGBKT7 empty vector were transformed into Y2HGold yeast cells respectively,and the PD-L1 IgV gene and its expression were detected by PCR and Western blot;Meanwhile,the protein toxicity and self-activation of PD-L1 IgV were detected,and the interaction between PD-L1 IgV and hTrx was detected by drip plate method.Results The bioinformatics analysis results of PD-L1 were consistent with related reports. The recombinant bait plasmid pGBKT7-PD-L1 IgV was correctly constructed,and Y2HGold positive clone was obtained,in which PD-L1 IgV was stably expressed. The empty vector pGBKT7 and recombinant bait plasmid pGBKT7-PD-L1 IgV grew well on SD/-Trp and SD/-Trp/X-α-Gal plates with the same colony size and number and white colony,but they did not grow on SD/-Trp/X-α-Gal/AbA plates,which indicated that PD-L1 IgV protein had no toxicity and no self-activation effect on yeast. The results of drip plates test showed that all experimental groups grew well on SD/-Trp/-Leu plate,while only positive control group grew on SD/-Trp/-Leu/X-α-Gal/AbA plate and showed blue color,which indicated that bait protein PD-L1 IgV and hTrx did not self-activate,and there was no interaction between them.Conclusion Recombinant human PD-L1 IgV bait plasmid was successfully constructed. PD-L1 IgV protein showed no toxicity and self-activation effect on yeast cells,and there was no interaction between PD-L1 IgV and hTrx. Subsequently,hTrx can be used to construct a peptide aptamer library,from which peptide aptamers that specifically bind to PD-L1 IgV can be screened.

Construction of bait plasmid containing SIGIRR cytoplasmic tail and detection of self-activation in yeast two hybrid system / 重庆医学

Objective To construct the bait plasmid of pSos-single immunoglobin IL-1 receptor related protein (SIGIRR) in Cy-toTrap yeast two hybrid system ,and to test its self-activation .Methods The cDNA fragments of SIGIRR(480 -1 230 bp) were amplified from pReceiver-LV19-SIGIRR and ligated into the bait plasmid pSos to generate the plasmid pSos-SIGIRR .The pSos-SI-GIRR was identified by DNA sequencing and dual-site endonuclease digestion .Then the recombinant plasmid and control plasmid were introduced into the yeast cell cdc25H .The transformants were inoculated on plates of 25 ℃ /SD/Glucose(-UL) ,25 ℃/SD/Ga-lactose(-UL) ,37 ℃ /SD/Glucose(-UL) and 37 ℃ /SD/Galactose ,respectively and the proliferation ability of transformant was ob-served for 6 d .The Western blot was adopted to detect the expression of target protein .Results The pSos-SIGIRR vector was cor-rectly constructed and proved of no self-activation and toxic action .The Western blot showed that the target protein was expressed in a form of fusion protein of 170KD .Conclusion The bait plasmid containing SIGIRR cytoplasmic tail can be applied to the yeast two-hybrid system and lays the important foundation for seeking the interacting protein with SIGRR from the human lung cDNA li-brary in .

Construction and Identification of a Yeast Two-Hybrid Bait Vector and Its Effect on the Growth of Yeast Cells and the Self-Activating Function of Reporter Genes for Screening of HPV18 E6-Interacting Protein / 华中科技大学学报（医学）（英德文版）

By using a yeast two-hybrid system,a yeast two-hybrid bait vector was constructed and identified for screening of the HPV18 E6-interacting proteins,and its effects on the growth of yeast cells and the activation of reporter genes were investigated.Total mRNA extracted from Hela cells was reversely transcribed into cDNA.Fragment of HPV18 E6 cDNA was amplified using RT-PCR and directly ligated to the pGBKT7 vector.The recombinant plasmid was confirmed by restriction endonuclease analysis and DNA sequencing.The recombinant pGBKT7-HPV18 E6 plasmid and empty pGBKT7 vector were transformed into the yeast cell AH109,respectively.After they were cultured respectively in YPDA liquid medium and nutrition-deficient culture medium,their toxicity and transcriptional activation were tested by both the phenotype assay and the color assay.The bait plasmid HPV18 E6 was successfully obtained.After being cultured in YPDA liquid medium for 16h,the A600 nm values of two yeast fluids were 0.98±0.03 and 0.99±0.02,respectively.The recombinant pGBKT7-HPV18 E6 plasmid and empty pGBKT7 vector could grow to white colonies on SD/-Trp/X-α-gal plates,while no colony could survive on SD/-His/-Trp/X-α-gal,SD/-Ade/-Trp/X-α-gal plates,indicating that the bait plasmid pGBKT7-HPV18 E6 was constructed successfully and expressed correctly,and could not activate the transcription of reporter gene alone.The yeast two-hybrid GAL4 system 3 can be utilized to find HPV18 E6 interacting proteins.

Construction and identification of bait plasmid carrying AMP-activated protein kinase ?2 in bacterial two-hybrid system / 第三军医大学学报

Objective To construct a bait plasmid in bacterial two-hybrid system.Methods A cDNA fragment encoding for rat AMP-activated protein kinase ?2(AMPK?2) was amplified by PCR and inserted into bacterial expression vector pBT.After confirmation with restricted endonuclease digestion and sequence analysis,bacterial reporter strain XL-1 Blue MRF' was transformed with pBT-AMPK?2 plasmid and the expression of the recombinant bait fusion protein was detected.To test whether the bait fusion protein had the capability of self-activation,the XL-1 Blue MRF' cells were cotransformed with the pBT-AMPK?2 plasmid and empty pTRG vector,and screened on 3-amino-1,2,4-triazole(3-AT) Selective Screening Medium plates.Results Restriction digestion and sequence analysis revealed that the AMPK?2 code sequence was correctly inserted into pBT with a right reading frame.pBT-AMPK?2 expressed ?cI/AMPK?2 fusion protein.Colonies were obtained on no 3-AT Nonselective Screening Medium plates when XL-1 Blue MRF' cells were cotransformed with recombinant pBT-AMPK?2 and empty pTRG vector,while none grew on 3-AT plates,indicating that the recombinant plasmid pBT-AMPK?2 expressed AMPK?2/?cI fusion protein correctly,and was incapable of activation of the reporter cassette in the absence of an interaction partner.Conclusion The recombinant plasmid pBT-AMPK?2 could be used as "bait plasmid" to screen cDNA library.

Expression and construction of "bait plasmid" containing human GR ligand-binding domain in yeast two-hybrid system / 第三军医大学学报

Objective To construct a bait vector containing human glucocorticoid receptor(GR) ligand binding domain (LBD) in yeast two hybrid system in order to screen its cDNA library Methods PCR was used to amplify GR LBD fragment from the fetal liver cDNA library with the primers designed in accordance with the sequence in GenBank GR LBD The product was inserted into pGEM(r) T Vector Systems After verified with restriction endonuclease digestion of SmaⅠ/SalⅡ, the vector was inserted into the "bait plasmid" pGBKT7 (named as pGBKT7 GR LBD) After confirmation with restricted endonuclease digestion and sequence analysis, the plasmid was transformed into the yeast cell AH109, and the transformants were selected on SD/ Trp plates The interaction between GR and SRC 1 was tested by ? gal activity with yeast two hybrid system Results The amplified product of 893 bp was inserted into pGEM(r) T Vector and proven to be successful with double restriction enzyme digestion Sequence analysis revealed that the sequence was correctly inserted into pGBKT7 with a right reading frame AH109 [pGBKT7 GR LBD] grew on SD/ Trp plates, but not on the other selective media GR could interact with SRC 1 Conclusion The bait plasmid pGBKT7 GR LBD constructed expresses GR LBD correctly, and can't activate the transcription of reporter gene alone in yeast two hybrid system