NMFS NUMBER: 96-SER-086
Utilization of Molecular Biomarkers to Provide an Assay
of Shellfish Exposure to Polyether Toxins from Harmful
H. Pierce, Michael S. Henry, Justine Lyons, and John S.
Marine Fisheries Service, Southeast Region, 9721 Executive
Center Drive, N., St Petersburg, FL 33702. TELEPHONE:
was undertaken to determine the sensitivity and selectivity
of protein biomarkers produced (expressed) in clams as
a result of exposure to polyether toxins from the toxic
dinoflagellate, Gymnodinium breve. Clams
(Merceneria merceneria) were exposed to live
G. breve cells for periods ranging from 3 to
21 days and subjected to depuration following exposure
for 14 days. Of five possible biomarkers observed
from preliminary investigations, two were consistently
expressed during the replicated experiments and only one
was found exclusively following toxin exposure. The results
indicate that the expression of the five protein biomarkers
was variable between exposure times and culture conditions.
Therefore these protein biomarkers failed to serve as
reliable markers of polyether toxin exposure in clams.
This study was undertaken as a follow-up investigation
of protein biomarkers induced in clams as a result of
exposure to brevetoxins. Preliminary investigations conducted
by Mote Marine Laboratory and the Medical University of
South Carolina identified five individual markers produced
in the siphon of M. merceneria in response to
exposure to G. breve. The markers correspondence
to elevated levels of brevetoxin in the clams as determined
by HPLC. Four of the markers were induced by exposure
to G. breve and one was extinguished.