Secreted Phospholipases A2 - not just Enzymes.

Secreted phospholipases A2 (sPLA2s) constitute, physiologically and pathologically, a very important family of enzymes. Most actions of sPLA2s have been explained by their phosphatidylglycerol sn-2 hydrolytic activity. However, since pharmacologically active sPLA2 molecules without enzymatic activity have been discovered, first in snake venom and then also in human, it has become increasingly evident that, on many occasions, the action of these proteins has to be considered as arising from the interplay of their receptor-binding and enzymatic functions. The number of known sPLA2-interacting molecules is growing and, with the development of more sensitive biochemical techniques, further discoveries are expected. In this paper we are reviewing all the currently known sPLA2-binding proteins. The structural versatility of these molecules establishes sPLA2s as ligands with a broad interaction spectrum, in agreement with the already recognized multifunctional nature of these proteins. Mechanistic descriptions of the multitude of actions of sPLA2s is today one of the most exciting and promising research areas, and the description of the sPLA2-interactome is for sure one of its vital parts.