Hainantoxin-I is a novel peptide toxin, purified from the venom of the Chinese bird spider Selenocosmia hainana(=Ornithoctonus hainana). It includes 33 amino acid residues with a disulfide linkage of I-IV, II-V and III-VI, assigned by partial reduction and sequence analysis. Under two-electrode voltage-clamp conditions, hainantoxin-I can block rNav1.2/B1 and the insect sodium channel para/tipE expressed in Xenopus laevis oocytes with IC50 values of 68

A neurotoxic peptide, named Hainantoxin-V (HNTX-V), was isolated from the venom of the Chinese bird spider Selenocosmia hainana. The complete amino acid sequence of HNTX-V has been determined by Edman degradation and found to contain 35 amino acid residues with three disulfide bonds. Under whole-cell patch-clamp mode, HNTX-V was proved to inhibit the tetrodotoxin-sensitive (TTX-S) sodium currents while it had no any effects on tetrodotoxin-resistant (TTX-R) sodium currents on adult rat dorsal root ganglion neurons. The inhibition of TTX-S sodium currents by HNTX-V was tested to be concentrate-dependent with the IC50 value of 42.3nM. It did not affect the activation and inactivation kinetics of currents and did not have the effect on the active threshold of sodium channels and the voltage of peak inward currents. However,100nM HNTX-V caused a 7.7mV hyperpolarizing shift in the voltage midpoint of steady-state sodium channel inactivation.The results indicated that HNTX-V inhibited mammalian voltage-gated sodium channels through a novel mechanism distinct from other spider toxins such as d-ACTXs, m-agatoxins I-VI which bind to receptor site three to slow the inactivation kinetics of sodium currents.

two toxins exhibits sequence identity with other spider toxins such as ProTx-I (64%), SGTx (57%), SNX-482 (55%), and Hanatoxin (54%). HWTX-V can reversibly paralyze locusts and cockroaches for several hours with a ED50 value as 16±5mg/g to locusts, and a larger dose of the toxin can cause death. However, mHWTX-V shows no significant effect on locusts and cockroaches. The structure–activity relationship indicates that the residues Phe34 and Ser35 in the C-terminus of HWTX-V are the key residues of the biological activity.c 2003 Elsevier Science Ltd. All rights reserved.

Two-dimensional polyacrylamide gel electrophoresis (2-DE) profiles of human lung squamous carcinoma tissue and paired surrounding normal bronchial epithelial tissue were compared. Selected differential protein-spots were identified with peptide mass fingerprinting based on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and database searching. Well-resolved and reproducible 2-DE patterns of both the tumor and the normal tissues were acquired. The average deviations of spot position were 0.873 0.125mm in IEF direction and 1.025 0.213mm in SDS–PAGE direction, respectively. For the tumor tissues, a total of 1349 67 spots were detected and 1235 48 spots were matched with an average matching rate of 91.5%. For the corresponding normal tissues, a total of 1297 73 spots were detected and 1183 56 spots were matched with an average matching rate of 91.2%. A total of 1069 45 spots were matched between the tumor and the normal tissues. Forty differential proteins between tumor and normal tissues were characterized. Some proteins were the products of oncogenes and others were involved in the regulation of cell cycle and signal transduction. These data are valuable for mass identification of differentially expressed proteins involved in lung carcinogenesis, establishing human lung cancer proteome databaseand screening molecular marker to further study human lung squamous carcinoma.2003 Published by Elsevier Inc.