Hello, kitty: could cat allergy be a form of intoxication?

Area of Science:

• Comparative genomics
• Protein evolution
• Mammalian toxicology

Background:

• The slow loris (Nycticebus spp.) venom (BGE protein) and the major cat allergen (Fel d 1) from domestic cats (Felis catus) exhibit known convergences.
• Evidence suggests these proteins share an almost identical mode of action.

Purpose of the Study:

• To investigate the evolutionary relationship and functional convergence between Fel d 1 and BGE proteins.
• To explore potential functions of Fel d 1 beyond its role as an allergen.
• To assess the possibility of domestic cats possessing toxic properties.

Main Methods:

• Large-scale database mining for Fel d 1 and BGE protein sequences in Felidae and Nycticebus spp.
• Sequence alignment, phylogenetic analysis, and molecular modeling.
• Directed literature review and comparative analysis.

Main Results:

• Identified Fel d 1 sequences in 28 non-domestic felids and two additional loris BGE protein sequences.
• Observed less conserved dimer interfaces and higher sequence similarity in chain 1 compared to chain 2.
• Found high probability of similarities in post-translational modifications.

Conclusions:

• Fel d 1 exhibits conserved functions in felids beyond allergy, potentially linked to toxicity.
• Domestication may explain the presence of toxicity solely in domestic cats.
• Comparative analysis suggests domestic cats could be potentially poisonous mammals.