title: Optimisation of the mRNA secondary structure to improve the expression of interleukin-24 (IL-24) in Escherichia coli.
abstract: Interleukin-24 (IL-24) is a novel cytokine selectively inhibiting proliferation of cancer cells but with little effect on normal cells. However, IL-24 is difficult to express in Escherichia coli. In this study, we optimised the secondary structure of the translation initiation region using computational approach to obtain non-fusion recombinant IL-24 (nrIL-24). The Gibbs free energy of the region was decreased from -22 to -9.07 kcal mol(-1), potentially promoting a loose secondary structure formation and improving the translation initiation efficiency. As a result, the expression of nrIL-24 was increased to 26 % of the total cellular protein from being barely initially detectable. nrIL-24 showed a concentration-dependent inhibition of A375 cells but had little effect on normal human cells. These results demonstrate that this method in increasing nrIL-24 expression is effective and efficient.
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, Shanghai, 200237, People's Republic of China.
authors.forename: Chaogang
authors.initials: C
authors.lastname: Bai
authors.forename: Xiaojuan
authors.initials: X
authors.lastname: Wang
authors.forename: Jian
authors.initials: J
authors.lastname: Zhang
authors.forename: Aiyou
authors.initials: A
authors.lastname: Sun
authors.forename: Dongzhi
authors.initials: D
authors.lastname: Wei
authors.forename: Shengli
authors.initials: S
authors.lastname: Yang
mesh_terms: D001483:Base Sequence; D002460:Cell Line; D002852:Chromatography, Ion Exchange; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000378:metabolism*; D015870:Gene Expression; D006801:Humans; D007378:Interleukins / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D010957:Plasmids / Q000378:metabolism; D012333:RNA, Messenger / Q000737:chemistry* / Q000235:genetics; D016415:Sequence Alignment; D013816:Thermodynamics; D000099180:Interleukin-24
chemical_list: D007378:Interleukins; D012333:RNA, Messenger; D000099180:Interleukin-24