title: Isolation and identification of a sodium channel-inhibiting protein from eggs of black widow spiders.
abstract: The eggs of black widow spider (L. tredecimguttatus) have been demonstrated to be rich in biologically active components that exhibit great research value and application foreground. In the present study, a protein toxin, named Latroeggtoxin-II, was isolated from the eggs using the combination of gel filtration, ion exchange chromatography and reversed-phase high performance liquid chromatography. Electrospray mass spectrometric analysis indicated that the molecular weight of the protein was 28.69 kDa, and Edman degradation revealed that its N-terminal sequence was ESIQT STYVP NTPNQ KFDYE VGKDY-. After being abdominally injected into mice and P. americana, the protein could make the animals especially P. americana display a series of poisoning symptoms. Electrophysiological experiments demonstrated that the protein could selectively inhibit tetrodotoxin-resistant Na(+) channel currents in rat dorsal root ganglion neurons, without significant effect on the tetrodotoxin-sensitive Na(+) channel currents. Using multiple proteomic strategies, the purified protein was shown to have only a few similarities to the existing proteins in the databases, suggesting that it was a novel protein isolated from the eggs of black widow spiders.
authors.affiliation: Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Li
authors.affiliation: Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Yizhong
authors.initials: Y
authors.lastname: Yan
authors.affiliation: Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Hai
authors.initials: H
authors.lastname: Yu
authors.affiliation: Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Xiaozhen
authors.initials: X
authors.lastname: Peng
authors.affiliation: Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Yiya
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Weijun
authors.initials: W
authors.lastname: Hu
authors.affiliation: Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, PR China.
authors.forename: Zhigui
authors.initials: Z
authors.lastname: Duan
authors.affiliation: Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, PR China. Electronic address: wang_xianchun@263.net.
authors.forename: Xianchun
authors.initials: X
authors.lastname: Wang
authors.affiliation: Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, PR China. Electronic address: liangsp@hunnu.edu.cn.
authors.forename: Songping
authors.initials: S
authors.lastname: Liang
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D060829:Arthropod Proteins / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification* / Q000633:toxicity*; D001740:Black Widow Spider / Q000737:chemistry*; D051379:Mice; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010063:Ovum / Q000737:chemistry*; D026941:Sodium Channel Blockers / Q000032:analysis / Q000737:chemistry / Q000302:isolation & purification* / Q000633:toxicity*; D015222:Sodium Channels / Q000378:metabolism*
chemical_list: D060829:Arthropod Proteins; D026941:Sodium Channel Blockers; D015222:Sodium Channels
keywords: Black widow spider; Characterization; Egg; Isolation; Protein; Toxin