Population differences in nerve resistance to paralytic shellfish toxins in softshell clam, <Emphasis Type="Italic">Mya arenaria</Emphasis>, associated with sodium channel mutations |
| |
| Authors: | Laurie B Connell Scott P MacQuarrie Betty M Twarog Melissa Iszard V Monica Bricelj |
| |
| Institution: | (1) School of Marine Sciences, University of Maine, Orono, ME 04469, USA;(2) Institute for Marine Biosciences, National Research Council, Halifax, NS, Canada, B3H 3Z1;(3) Darling Marine Center, University of Maine, Walpole, ME 04573, USA |
| |
| Abstract: | The softshell clam, Mya arenaria, is a commercially important bivalve with wide latitudinal distribution in North America. Populations of clams with a history
of repeated exposure to toxic Alexandrium spp. have developed a natural resistance to the paralytic shellfish toxins (PSTs) produced by these algae. An association
between PST resistance in individual clams and a single mutation in the saxitoxin (STX) binding region of the α-subunit of
the voltage-gated sodium (Na+) channel gene was previously identified. Here we establish that more than one mutation associated with nerve resistance to
STX occurred at this locus. Both cDNA from mRNA and genomic DNA sequences from individual clams are identical demonstrating
that both alleles are expressed simultaneously. In addition, one resistant allele per individual is sufficient to confer neural
resistance to STX even though heterozygous individuals show an intermediate level of resistance to STX in in vitro nerve trunk
assays. |
| |
| Keywords: | |
| 本文献已被 SpringerLink 等数据库收录！ |
|
