Mutations in voltage-gated sodium channels from pyrethroid resistant salmon lice (Lepeophtheirus salmonis).
Pest Manag Sci
; 75(2): 527-536, 2019 Feb.
Article
in En
| MEDLINE
| ID: mdl-30062864
ABSTRACT
BACKGROUND:
Parasitic salmon lice (Lepeophtheirus salmonis) cause high economic losses in Atlantic salmon farming. Pyrethroids, which block arthropod voltage-gated sodium channels (Nav 1), are used for salmon delousing. However, pyrethroid resistance is common in L. salmonis. The present study characterized Nav 1 homologues in L. salmonis in order to identify channel mutations associated to resistance, called kdr (knockdown) mutations.RESULTS:
Genome scans identified three L. salmonis Nav 1 homologues, LsNav 1.1, LsNav 1.2 and LsNav 1.3. Arthropod kdr mutations map to specific Nav 1 regions within domains DI-III, namely segments S5 and S6 and the linker helix connecting S4 and S5. The above channel regions were amplified by RT-PCR and sequenced in deltamethrin-susceptible and deltamethrin-resistant L. salmonis. While LsNav 1.1 and LsNav 1.2 lacked nucleotide polymorphisms showing association to resistance, LsNav 1.3 showed a non-synonymous mutation in S5 of DII occurring in deltamethrin-resistant parasites. The mutation is homologous to a previously described kdr mutation (I936V, numbering according to Musca domestica Vssc1) and was present in two pyrethroid-resistant L. salmonis strains (allele frequencies of 0.800 and 0.357), but absent in two pyrethroid-susceptible strains.CONCLUSIONS:
The present study indicates that a kdr-mutation in LsNaV 1.3 may contribute to deltamethrin resistance in L. salmonis. © 2018 Society of Chemical Industry.Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Pyrethrins
/
Insecticide Resistance
/
Copepoda
/
Voltage-Gated Sodium Channels
/
Insecticides
/
Mutation
/
Nitriles
Limits:
Animals
Language:
En
Journal:
Pest Manag Sci
Journal subject:
TOXICOLOGIA
Year:
2019
Document type:
Article
Affiliation country:
United kingdom
Publication country:
ENGLAND
/
ESCOCIA
/
GB
/
GREAT BRITAIN
/
INGLATERRA
/
REINO UNIDO
/
SCOTLAND
/
UK
/
UNITED KINGDOM