Since the discovery of PLA2 activity in snake venoms and the later characterization of the first isolated enzymes, scientists interested in this group of venom components have come a long way in understanding their basic structural and functional aspects. A great number of sequences and crystal structures have been elucidated, and the molecular landscape of venom PLA2 evolution has been largely unveiled. Many pharmacological/toxicological activities have been described, some of which are clearly associated with the pathophysiology of snakebite envenoming, whereas others are being explored for the design of new drugs. Understanding this wide functional profile vis-à-vis a conserved 3D structure has prompted a significant amount of work aimed at identifying the molecular regions associated with each effect and at analyzing the role of enzymatic activity in toxicity. Furthermore, important advances in the study of the mechanisms of neurotoxicity, myotoxicity and other effects by venom PLA2s have been performed, and the ‘acceptors’ of several of these toxins characterized. Nevertheless, many aspects of the structure and function of PLA2s present in snake venoms are still a mystery, and new enzymes present in less studied venoms, such as those of ‘colubrid’ and many viperid and elapid species, need to be discovered and characterized. The cellular targets of many toxic PLA2s remain to be identified. Likewise, the study of venom PLA2s is likely to shed light on unknown physiological roles of their mammalian counterparts. In addition to toxicity, the bio- logical roles of PLA s in snake venoms are largely unknown and demand further investigation, such as the adaptive
value of catalytically-inactive PLA2 homologues of low toxicity present in large amounts in many venoms. Finally, harnessing all this information for the design of novel research, diagnostic and therapeutic tools constitutes a challenging task, together with the search for novel inhibitors of PLA2s using venom enzymes as tools (Table 1). Understanding such complex landscape of venom PLA2s will demand renewed integrative approaches involving various scientific disciplines. It is expected that the contributions discussed in this work will motivate young researchers and students to undertake the challenge of fostering PLA2 venom research.