title: Characterization of a novel BmαTX47 toxin modulating sodium channels: the crucial role of expression vectors in toxin pharmacological activity.
abstract: Long-chain scorpion toxins with four disulfide bridges exhibit various pharmacological features towards the different voltage-gated sodium channel subtypes. However, the toxin production still remains a huge challenge. Here, we reported the effects of different expression vectors on the pharmacological properties of a novel toxin BmαTX47 from the scorpion Buthus martensii Karsch. The recombinant BmαTX47 was obtained using the expression vector pET-14b and pET-28a, respectively. Pharmacological experiments showed that the recombinant BmαTX47 was a new α-scorpion toxin which could inhibit the fast inactivation of rNa(v)1.2, mNa(v)1.4 and hNa(v)1.5 channels. Importantly, the different expression vectors were found to strongly affect BmαTX47 pharmacological activities while toxins were obtained by the same expression and purification procedures. When 10 µM recombinant BmαTX47 from the pET-28a vector was applied, the values of I(5ms)/I(peak) for rNa(v)1.2, mNa(v)1.4 and hNa(v)1.5 channels were 44.12% ± 3.17%, 25.40% ± 4.89% and 65.34% ± 3.86%, respectively, which were better than those values of 11.33% ± 1.46%, 15.96% ± 1.87% and 5.24% ± 2.38% for rNa(v)1.2, mNa(v)1.4 and hNa(v)1.5 channels delayed by 10 µM recombinant BmαTX47 from the pET-14b vector. The dose-response experiments further indicated the EC50 values of recombinant BmαTX47 from the pET-28a vector were 7262.9 ± 755.9 nM for rNa(v)1.2 channel and 1005.8 ± 118.6 nM for hNa(v)1.5 channel, respectively. Together, these findings highlighted the important role of expression vectors in scorpion toxin pharmacological properties, which would accelerate the understanding of the structure-function relationships of scorpion toxins and promote the potential application of toxins in the near future.
authors.affiliation: State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China. fiona2210@163.com.
authors.forename: Tian
authors.initials: T
authors.lastname: Li
authors.affiliation: State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China. xulingna58@126.com.
authors.forename: Lingna
authors.initials: L
authors.lastname: Xu
authors.affiliation: State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China. honglianliu2011@whu.edu.cn.
authors.forename: Honglian
authors.initials: H
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China. hesunrise@sohu.com.
authors.forename: Yawen
authors.initials: Y
authors.lastname: He
authors.affiliation: Key Laboratory of Protein Chemistry and Developmental Biology of the Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, Hunan, China. liangsp@hunnu.edu.cn.
authors.forename: Songping
authors.initials: S
authors.lastname: Liang
authors.affiliation: State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China. liwxlab@whu.edu.cn.
authors.forename: Wenxin
authors.initials: W
authors.lastname: Li
authors.affiliation: State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072, China. ylwu@whu.edu.cn.
authors.forename: Yingliang
authors.initials: Y
authors.lastname: Wu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015870:Gene Expression; D005822:Genetic Vectors; D057809:HEK293 Cells; D006801:Humans; D008969:Molecular Sequence Data; D010957:Plasmids; D012604:Scorpion Venoms / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology*; D012605:Scorpions; D016415:Sequence Alignment; D015222:Sodium Channels / Q000502:physiology*
chemical_list: D012604:Scorpion Venoms; D015222:Sodium Channels