title: Physiological and biochemical characterization of egg extract of black widow spiders to uncover molecular basis of egg toxicity.
abstract: BACKGROUND
  Black widow spider (L. tredecimguttatus) has toxic components not only in the venomous glands, but also in other parts of the body and its eggs. It is biologically important to investigate the molecular basis of the egg toxicity.
  
  
  RESULTS
  In the present work, an aqueous extract was prepared from the eggs of the spider and characterized using multiple physiological and biochemical strategies. Gel electrophoresis and mass spectrometry demonstrated that the eggs are rich in high-molecular-mass proteins and the peptides below 5 kDa. The lyophilized extract of the eggs had a protein content of 34.22% and was shown to have a strong toxicity towards mammals and insects. When applied at a concentration of 0.25 mg/mL, the extract could completely block the neuromuscular transmission in mouse isolated phrenic nerve-hemidiaphragm preparations within 12.0 ± 1.5 min. Using whole-cell patch-clamp technique, the egg extract was demonstrated to be able to inhibit the voltage-activated Na+, K+ and Ca2+ currents in rat DRG neurons. In addition, the extract displayed activities of multiple hydrolases. Finally, the molecular basis of the egg toxicity was discussed.
  
  
  CONCLUSIONS
  The eggs of black widow spiders are rich in proteinous compounds particularly the high-molecular-mass proteins with different types of biological activity The neurotoxic and other active compounds in the eggs are believed to play important roles in the eggs' toxic actions.
authors.forename: Yizhong
authors.initials: Y
authors.lastname: Yan
authors.forename: Jianjun
authors.initials: J
authors.lastname: Li
authors.forename: Yiya
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xiaozhen
authors.initials: X
authors.lastname: Peng
authors.forename: Tianyao
authors.initials: T
authors.lastname: Guo
authors.forename: Jirong
authors.initials: J
authors.lastname: Wang
authors.forename: Weijun
authors.initials: W
authors.lastname: Hu
authors.forename: Zhigui
authors.initials: Z
authors.lastname: Duan
authors.forename: Xianchun
authors.initials: X
authors.lastname: Wang
mesh_terms: D060105:Animal Shells / Q000737:chemistry / Q000502:physiology; D000818:Animals; D060829:Arthropod Proteins / Q000302:isolation & purification / Q000633:toxicity*; D001740:Black Widow Spider / Q000737:chemistry*; D015220:Calcium Channels / Q000187:drug effects; D003058:Cockroaches / Q000187:drug effects; D005727:Ganglia, Spinal / Q000187:drug effects; D051379:Mice; D010063:Ovum / Q000737:chemistry* / Q000502:physiology; D010791:Phrenic Nerve / Q000187:drug effects; D024642:Potassium Channels, Voltage-Gated / Q000187:drug effects; D051381:Rats; D014020:Tissue Extracts / Q000737:chemistry* / Q000633:toxicity; D061566:Voltage-Gated Sodium Channels / Q000187:drug effects
chemical_list: D060829:Arthropod Proteins; D015220:Calcium Channels; D024642:Potassium Channels, Voltage-Gated; D014020:Tissue Extracts; D061566:Voltage-Gated Sodium Channels