title: A minimal cytomegalovirus intron A variant can improve transgene expression in different mammalian cell lines.
abstract: The expression enhancement by cytomegalovirus promoter and different intron A (IA) variants were evaluated in CHO-K1, HepG2, HEK-293 and COS-7 cells by assessing the levels of luciferase activity. This data along with mRNA levels measurement indicated that the construct harboring an IA variant with a 200-nucleotide deletion (Δ200) had the greatest impact on increasing luciferase expression among all constructs evaluated. Based on these results, we redesigned pCMV-IA variants and cloned them into plasmids expressing a humanized antibody. These plasmids were then used to transfect CHO-K1 cells. Production of the antibody was not augmented with the Δ200 promoter variant. The 600-nucleotide deletion (Δ600) and whole IA promoter variants expressed similar levels of the recombinant protein. These data indicate that the IA-based enhanced expression of transgenes depends on a small region within the intron.
authors.affiliation: Instituto de Ciências Biológicas, Departamento de Biologia Celular, Laboratório de Imunologia Molecular, Universidade de Brasília, Campus Universitário Darcy Ribeiro, Brasília, DF, Brazil.
authors.forename: L S
authors.initials: LS
authors.lastname: Quilici
authors.forename: I
authors.initials: I
authors.lastname: Silva-Pereira
authors.forename: A C
authors.initials: AC
authors.lastname: Andrade
authors.forename: F C
authors.initials: FC
authors.lastname: Albuquerque
authors.forename: M M
authors.initials: MM
authors.lastname: Brigido
authors.forename: A Q
authors.initials: AQ
authors.lastname: Maranhão
mesh_terms: D000818:Animals; D001709:Biotechnology; D016466:CHO Cells; D019556:COS Cells; D002522:Chlorocebus aethiops; D006224:Cricetinae; D003412:Cricetulus; D003587:Cytomegalovirus / Q000235:genetics*; D015870:Gene Expression; D057809:HEK293 Cells; D006801:Humans; D007438:Introns; D008156:Luciferases / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D019076:Transgenes
chemical_list: D012333:RNA, Messenger; D011994:Recombinant Proteins; D008156:Luciferases