Publication Date:
2022-05-25
Description:
Author Posting. © The Author(s), 2010. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology 152 (2010): 288-300, doi:10.1016/j.cbpc.2010.05.003.
Description:
Multixenobiotic transporters have been extensively studied for their ability to modulate the
disposition and toxicity of pharmacological agents, yet their influence in regulating the levels of
dietary toxins within marine consumers has only recently been explored. This study presents
functional and molecular evidence for multixenobiotic transporter-mediated efflux activity and
expression in the generalist gastropod Cyphoma gibbosum, and the specialist nudibranch Tritonia
hamnerorum, obligate predators of chemically defended gorgonian corals. Immunochemical
analysis revealed that proteins with homology to permeability glycoprotein (P-gp) were highly
expressed in T. hamnerorum whole animal homogenates and localized to the apical tips of the
gut epithelium, a location consistent with a role in protection against ingested prey toxins. In
vivo dye assays with specific inhibitors of efflux transporters demonstrated the activity of P-gp
and multidrug resistance-associated protein (MRP) families of ABC transporters in T.
hamnerorum. In addition, we identified eight partial cDNA sequences encoding two ABCB and
two ABCC proteins from each molluscan species. Digestive gland transcripts of C. gibbosum
MRP-1, which have homology to vertebrate glutathione-conjugate transporters, were
constitutively expressed regardless of gorgonian diet. This constitutive expression may reflect
the ubiquitous presence of high affinity substrates for C. gibbosum glutathione transferases in
gorgonian tissues likely necessitating export by MRPs. Our results suggest that differences in
multixenobiotic transporter expression patterns and activity in molluscan predators may stem
from the divergent foraging strategies of each consumer.
Description:
Financial support was provided by the Ocean Life Institute Tropical Research
Initiative Grant (WHOI) to KEW and MEH; the Robert H. Cole Endowed Ocean Ventures Fund
(WHOI) to KEW; the National Undersea Research Center – Program Development Proposal
(CMRC-03PRMN0103A) to KEW; and the National Science Foundation (Graduate Research
Fellowship to KEW and DEB-0919064 to EES).
Keywords:
ABC transporter
;
Allelochemical
;
Calcein-am
;
Gorgonian
;
MK571
;
MRP
;
P-gp
;
Verapamil
Repository Name:
Woods Hole Open Access Server
Type:
Preprint
Format:
application/pdf
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