Author:
Saviola Anthony J,Chiszar David,Busch Chardelle,Mackessy Stephen P
Abstract
Abstract
Background
Vertebrate predators use a broad arsenal of behaviors and weaponry for overcoming fractious and potentially dangerous prey. A unique array of predatory strategies occur among snakes, ranging from mechanical modes of constriction and jaw-holding in non-venomous snakes, to a chemical means, venom, for quickly dispatching prey. However, even among venomous snakes, different prey handling strategies are utilized, varying from the strike-and-hold behaviors exhibited by highly toxic elapid snakes to the rapid strike-and-release envenomation seen in viperid snakes. For vipers, this mode of envenomation represents a minimal risk predatory strategy by permitting little contact with or retaliation from prey, but it adds the additional task of relocating envenomated prey which has wandered from the attack site. This task is further confounded by trails of other unstruck conspecific or heterospecific prey. Despite decades of behavioral study, researchers still do not know the molecular mechanism which allows for prey relocation.
Results
During behavioral discrimination trials (vomeronasal responsiveness) to euthanized mice injected with size-fractionated venom, Crotalus atrox responded significantly to only one protein peak. Assays for enzymes common in rattlesnake venoms, such as exonuclease, L-amino acid oxidase, metalloproteinase, thrombin-like and kallikrein-like serine proteases and phospholipase A2, showed that vomeronasal responsiveness was not dependent on enzymatic activity. Using mass spectrometry and N-terminal sequencing, we identified the proteins responsible for envenomated prey discrimination as the non-enzymatic disintegrins crotatroxin 1 and 2. Our results demonstrate a novel and critical biological role for venom disintegrins far beyond their well-established role in disruption of cell-cell and cell-extracellular matrix interactions.
Conclusions
These findings reveal the evolutionary significance of free disintegrins in venoms as the molecular mechanism in vipers allowing for effective relocation of envenomated prey. The presence of free disintegrins in turn has led to evolution of a major behavioral adaptation (strike-and-release), characteristic of only rattlesnakes and other vipers, which exploits and refines the efficiency of a pre-existing chemical means of predation and a highly sensitive olfaction system. This system of a predator chemically tagging prey represents a novel trend in the coevolution of predator-prey relationships.
Publisher
Springer Science and Business Media LLC
Subject
Cell Biology,Developmental Biology,Plant Science,General Agricultural and Biological Sciences,General Biochemistry, Genetics and Molecular Biology,Physiology,Ecology, Evolution, Behavior and Systematics,Structural Biology,Biotechnology
Reference49 articles.
1. Tinbergen N: The Study of Instinct. 1951, London: Oxford University Press
2. Geffeney S, Brodie ED, Ruben PC, Brodie ED III: Mechanisms of adaptation in a predator-prey arms race: TTX-resistant sodium channels. Science. 2002, 297: 1336-1339. 10.1126/science.1074310.
3. Abrams PA: The evolution of predator-prey interactions: theory and evidence. Annu Rev Ecol Syst. 2000, 31: 79-105. 10.1146/annurev.ecolsys.31.1.79.
4. Darwin C: On the Origin of Species by Means of Natural Selection. 1859, London: John Murray
5. Stewart TA, Albertson RC: Evolution of a unique predatory feeding apparatus: functional anatomy, development and a genetic locus for jaw laterality in Lake Tanganyika scale-eating cichlids. BMC Biol. 2010, 8: 8-10.1186/1741-7007-8-8.
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