Publication Date:
2013-10-26
Description:
Painful venoms are used to deter predators. Pain itself, however, can signal damage and thus serves an important adaptive function. Evolution to reduce general pain responses, although valuable for preying on venomous species, is rare, likely because it comes with the risk of reduced response to tissue damage. Bark scorpions capitalize on the protective pain pathway of predators by inflicting intensely painful stings. However, grasshopper mice regularly attack and consume bark scorpions, grooming only briefly when stung. Bark scorpion venom induces pain in many mammals (house mice, rats, humans) by activating the voltage-gated Na(+) channel Nav1.7, but has no effect on Nav1.8. Grasshopper mice Nav1.8 has amino acid variants that bind bark scorpion toxins and inhibit Na(+) currents, blocking action potential propagation and inducing analgesia. Thus, grasshopper mice have solved the predator-pain problem by using a toxin bound to a nontarget channel to block transmission of the pain signals the venom itself is initiating.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4172297/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉 〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4172297/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Rowe, Ashlee H -- Xiao, Yucheng -- Rowe, Matthew P -- Cummins, Theodore R -- Zakon, Harold H -- NS 053422/NS/NINDS NIH HHS/ -- R01 NS053422/NS/NINDS NIH HHS/ -- New York, N.Y. -- Science. 2013 Oct 25;342(6157):441-6. doi: 10.1126/science.1236451.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Section of Neurobiology, The University of Texas at Austin, Austin, TX 78712, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24159039" target="_blank"〉PubMed〈/a〉
Keywords:
Action Potentials/drug effects/physiology
;
Amino Acid Sequence
;
Animals
;
Arvicolinae/*metabolism
;
*Food Chain
;
Formaldehyde/pharmacology
;
Mice
;
Molecular Sequence Data
;
NAV1.7 Voltage-Gated Sodium Channel/chemistry/genetics/*metabolism
;
NAV1.8 Voltage-Gated Sodium Channel/chemistry/genetics/*metabolism
;
Pain/chemically induced/*metabolism
;
*Predatory Behavior
;
Protein Structure, Tertiary
;
Scorpion Venoms
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
