Latrodectus mactans venom protein

Latrodectus mactans venom proteins refer to the diverse mixture of biologically active macromolecules in the venom of the black widow spider. The most studied are the latrotoxin family, notably α-latrotoxin (α-LTX), a presynaptic neurotoxin that specifically targets vertebrate neurons, causing massive neurotransmitter release and the characteristic symptoms of latrodectism. The venom also contains multiple insectotoxins (LITs), a crustacean-specific toxin (LCT), and a variety of enzymes including proteases and hyaluronidases, which aid in toxin dissemination and prey immobilization. These proteins have high molecular weight (typically ~100–140 kDa for latrotoxins) and act by forming calcium-permeable membrane pores and inducing exocytosis, leading to rapid synaptic vesicle depletion. As a group, they do not constitute a single druggable therapeutic target, but have served as molecular tools in research on neurotransmitter release, and are clinically relevant due to their toxic effects in envenomation. The term "Latrodectus mactans venom proteins" is broad and imprecise for a therapeutic target, as it encompasses many structurally and functionally distinct components, rather than a single molecule or receptor that can be selectively targeted by drugs.

Other names

Black widow spider venom proteinsLatrodectus venom proteinsLatrotoxins (specific protein family within the venom)α-latrotoxin (α-LTX) (most prominent member)Latroinsectotoxins (LITs – β, γ, δ, ε)Latrocrustatoxin (α-LCT)

Pore formation in neuronal membranes (latrotoxins); Induction of massive neurotransmitter release (presynaptic membrane exocytosis stimulation, primarily by α-latrotoxin); Enzymatic degradation of extracellular matrix (hyaluronidase/facilitate tissue penetration); Proteolytic cleavage of other venom protein precursors