Spatial VenomicsCobra Venom System Reveals Spatial Differentiation of Snake Toxins by Mass Spectrometry Imaging

Among venomous animals, toxic secretions have evolved
as biochemical
weapons associated with various highly specialized delivery systems
on many occasions. Despite extensive research, there is still limited
knowledge of the functional biology of most animal toxins, including
their venom production and storage, as well as the morphological structures
within sophisticated venom producing tissues that might underpin venom
modulation. Here, we report on the spatial exploration of a snake
venom gland system by matrix-assisted laser desorption/ionization
mass spectrometry imaging (MALDI-MSI), in combination with standard
proteotranscriptomic approaches, to enable in situ toxin mapping in
spatial intensity maps across a venom gland sourced from the Egyptian
cobra (Naja haje). MALDI-MSI toxin
visualization on the elapid venom gland reveals a high spatial heterogeneity
of different toxin classes at the proteoform level, which may be the
result of physiological constraints on venom production and/or storage
that reflects the potential for venom modulation under diverse stimuli.