scholarly journals Acetylcholinesterase point mutations in European strains of Tetranychus urticae (Acari: Tetranychidae) resistant to organophosphates

2009 ◽  
Vol 66 (2) ◽  
pp. 220-228 ◽  
Author(s):  
Jahangir Khajehali ◽  
Thomas Van Leeuwen ◽  
Maria Grispou ◽  
Evangelia Morou ◽  
Haoués Alout ◽  
...  
Keyword(s):  
Tetranychus Urticae ◽  
Point Mutations

scholarly journals Target-Site Mutations and Glutathione S-Transferases Are Associated with Acequinocyl and Pyridaben Resistance in the Two-Spotted Spider Mite Tetranychus urticae (Acari: Tetranychidae)

Insects ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 511 ◽  
Author(s):  
Jihye Choi ◽  
Hyun-Na Koo ◽  
Sung Il Kim ◽  
Bueyong Park ◽  
Hyunkyung Kim ◽  
...  
Keyword(s):  
Tetranychus Urticae ◽  
Spider Mite ◽  
Point Mutations ◽  
Cross Resistance ◽  
Glutathione S Transferase ◽  
Short Life ◽  
Resistance Development ◽  
Glutathione S Transferases ◽  
Two Spotted Spider Mite ◽  
Gst Activity

The two-spotted spider mite Tetranychus urticae is a difficult-to-control pest due to its short life cycle and rapid resistance development. In this study, we characterized field strains collected in 2001 and 2003 that were selected for acequinocyl resistance (AR) and pyridaben resistance (PR), respectively. These strains displayed resistance ratios of 1798.6 (susceptible vs. AR) and 5555.6 (susceptible vs. PR), respectively, and were screened for cross-resistance against several currently used acaricides. The AR strain exhibited pyridaben cross-resistance, but the PR strain showed no cross-resistance. The AR strain exhibited point mutations in cytb (I256V, N321S) and PSST (H92R). In contrast, the PR strain exhibited the H92R but not the I256V and N321S point mutations. In some cases increased glutathione S-transferase (GST) activity has previously been linked to enhanced detoxification. The AR strain exhibited approximately 2.3-, 1.8-, and 2.2-fold increased GST activity against 1-chloro-2,4-dinitrobenzene (CDNB), 1,2-dichloro-4-nitrobenzene (DCNB), and 4-nitrobenzyl chloride (NBC), respectively. Among the five GST subclass genes (delta, omega, mu, zeta, and kappa), the relative expression of delta class GSTs in the AR strain were significantly higher than the PR and susceptible strain. These results suggest that the I256V and N321S mutations and the increased GST metabolism and GST delta overexpression might be related to acequinocyl resistance in T. urticae.

scholarly journals Susceptibility to Acaricides and the Frequencies of Point Mutations in Etoxazole- and Pyridaben-Resistant Strains and Field Populations of the Two-Spotted Spider Mite, Tetranychus urticae (Acari: Tetranychidae)

Insects ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 660
Author(s):  
Hyun-Na Koo ◽  
Jihye Choi ◽  
Eungyeong Shin ◽  
Wonjin Kang ◽  
Sun-Ran Cho ◽  
...  
Keyword(s):  
Point Mutation ◽  
Tetranychus Urticae ◽  
High Frequency ◽  
Spider Mite ◽  
Point Mutations ◽  
Cross Resistance ◽  
Resistance Patterns ◽  
Resistant Strains ◽  
Two Spotted Spider Mite ◽  
Tetranychus Urticae Koch

The two-spotted spider mite Tetranychus urticae Koch is a major agricultural pest worldwide and is known to rapidly develop resistance to pesticides. In the present study, we explored a field strain that was collected in 2000 and 2003 and has been exhibiting resistance to etoxazole and pyridaben over the last 16 years. The resistance ratios of the etoxazole- and pyridaben-resistant strains (ER and PR) to etoxazole or pyridaben were more than 5,000,000- and 4109.6-fold higher than that of the susceptible strain, respectively. All field-collected populations showed resistance to etoxazole and pyridaben. The ER and PR strains showed cross-resistance to several acaricides. Both I1017F and H92R point mutations were detected in 7 out of 8 field groups. Spirodiclofen and spiromesifen resulted in more than 77.5% mortality in the 8 field groups. In addition, the genotype frequency of the I1017F point mutation was 100.0% in the ER strain, and that of the H92R point mutation was 97.0% in the PR strain. All of the field populations were found to have a high frequency of I1017F. These results suggest that the observation of resistance patterns will help in designing a sustainable IPM program for T. urticae.

A Novel Mutation Glyl672→Arg in Type 2A and a Homozygous Mutation in Type 2B von Willebrand Disease

1996 ◽  
Vol 76 (02) ◽  
pp. 253-257 ◽  
Author(s):  
Takeshi Hagiwara ◽  
Hiroshi Inaba ◽  
Shinichi Yoshida ◽  
Keiko Nagaizumi ◽  
Morio Arai ◽  
...  
Keyword(s):  
Missense Mutation ◽  
Novel Mutation ◽  
Point Mutations ◽  
Japanese Patients ◽  
Von Willebrand Disease ◽  
Homozygous Mutation ◽  
Missense Mutations ◽  
Reaction Products ◽  
Type 3 ◽  
Von Willebrand

SummaryGenetic materials from 16 unrelated Japanese patients with von Willebrand disease (vWD) were analyzed for mutations. Exon 28 of the von Willebrand factor (vWF) gene, where point mutations have been found most frequent, was screened by various restriction-enzyme analyses. Six patients were observed to have abnormal restriction patterns. By sequence analyses of the polymerase chain-reaction products, we identified a homozygous R1308C missense mutation in a patient with type 2B vWD; R1597W, R1597Q, G1609R and G1672R missense mutations in five patients with type 2A; and a G1659ter nonsense mutation in a patient with type 3 vWD. The G1672R was a novel missense mutation of the carboxyl-terminal end of the A2 domain. In addition, we detected an A/C polymorphism at nucleotide 4915 with HaeIII. There was no particular linkage disequilibrium of the A/C polymorphism, either with the G/A polymorphism at nucleotide 4391 detected with Hphl or with the C/T at 4891 detected with BstEll.

PREVALENCE OF COMMON MITOCHONDRIAL POINT MUTATIONS IN AUTISM

2006 ◽  
Vol 37 (S 1) ◽  
Author(s):  
FJ Serajee ◽  
H Zhong ◽  
AHMM Huq
Keyword(s):  
Point Mutations
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