Navajas M

References (3)

Title : The genome of Tetranychus urticae reveals herbivorous pest adaptations - Grbic_2011_Nature_479_487
Author(s) : Grbic M , Van Leeuwen T , Clark RM , Rombauts S , Rouze P , Grbic V , Osborne EJ , Dermauw W , Ngoc PC , Ortego F , Hernandez-Crespo P , Diaz I , Martinez M , Navajas M , Sucena E , Magalhaes S , Nagy L , Pace RM , Djuranovic S , Smagghe G , Iga M , Christiaens O , Veenstra JA , Ewer J , Villalobos RM , Hutter JL , Hudson SD , Velez M , Yi SV , Zeng J , Pires-daSilva A , Roch F , Cazaux M , Navarro M , Zhurov V , Acevedo G , Bjelica A , Fawcett JA , Bonnet E , Martens C , Baele G , Wissler L , Sanchez-Rodriguez A , Tirry L , Blais C , Demeestere K , Henz SR , Gregory TR , Mathieu J , Verdon L , Farinelli L , Schmutz J , Lindquist E , Feyereisen R , Van de Peer Y
Ref : Nature , 479 :487 , 2011
Abstract : The spider mite Tetranychus urticae is a cosmopolitan agricultural pest with an extensive host plant range and an extreme record of pesticide resistance. Here we present the completely sequenced and annotated spider mite genome, representing the first complete chelicerate genome. At 90 megabases T. urticae has the smallest sequenced arthropod genome. Compared with other arthropods, the spider mite genome shows unique changes in the hormonal environment and organization of the Hox complex, and also reveals evolutionary innovation of silk production. We find strong signatures of polyphagy and detoxification in gene families associated with feeding on different hosts and in new gene families acquired by lateral gene transfer. Deep transcriptome analysis of mites feeding on different plants shows how this pest responds to a changing host environment. The T. urticae genome thus offers new insights into arthropod evolution and plant-herbivore interactions, and provides unique opportunities for developing novel plant protection strategies.
ESTHER : Grbic_2011_Nature_479_487
PubMedSearch : Grbic_2011_Nature_479_487
PubMedID: 22113690
Gene_locus related to this paper: tetur-ACHE

Title : Mechanisms of resistance to organophosphates in Tetranychus urticae (Acari: Tetranychidae) from Greece - Tsagkarakou_2002_Insect.Biochem.Mol.Biol_32_417
Author(s) : Tsagkarakou A , Pasteur N , Cuany A , Chevillon C , Navajas M
Ref : Insect Biochemistry & Molecular Biology , 32 :417 , 2002
Abstract : We investigated the mechanisms conferring resistance to methyl-parathion (44-fold) and to methomyl (8-fold) in Tetranychus urticae from Greece by studying the effect of synergists on the resistance and the kinetic characteristics of various enzymes in a resistant strain (RLAB) and a susceptible reference strain (SAMB). It is shown that S,S,S-tributyl phosphorotrithioate, a synergist that inhibits esterases and glutathione S-transferases, and piperonyl butoxide, a synergist that inhibits cytochrome P450 mediated monooxygenases, did not affect the level of methyl-parathion or methomyl resistance in RLAB and that resistance ratios to both insecticides did not change significantly in the presence of either synergist. Isoelectric focusing of esterase allozymes on single mites revealed no differences in staining intensity and glutathione S-transferase activity was not significantly different in the two strains. The activity of two cytochrome P450 monooxygenase groups was compared. No significant difference of 7-ethoxyresorufin-O-diethylase activity was observed between strains that were two-fold higher in RLAB than in SAMB. The kinetic characteristics of acetylcholinesterase, the target enzyme of organophosphates and carbamates, revealed that acetylcholinesterase in RLAB was less sensitive to inhibition by paraoxon and methomyl in comparison with SAMB. I(50), the inhibitor concentration inducing 50% decrease of acetylcholinesterase activity was greater (119- and 50-fold with paraoxon and methomyl, respectively) and the bimolecular constant k(i) was lower (39- and 47-fold with paraoxon and methomyl, respectively) in RLAB compared to SAMB.
ESTHER : Tsagkarakou_2002_Insect.Biochem.Mol.Biol_32_417
PubMedSearch : Tsagkarakou_2002_Insect.Biochem.Mol.Biol_32_417
PubMedID: 11886776

Title : Mechanisms of insecticide resistance in the aphid Nasonovia ribisnigri (Mosley) (Homoptera: Aphididae) from France - Rufingier_1999_Insect.Biochem.Mol.Biol_29_385
Author(s) : Rufingier C , Pasteur N , Lagnel J , Martin C , Navajas M
Ref : Insect Biochemistry & Molecular Biology , 29 :385 , 1999
Abstract : Nasonovia ribisnigri, a main pest of salad crops, has developed resistance to various insecticides in southern France, including the carbamate pirimicarb and the cyclodiene endosulfan, two insecticides widely used to control this aphid. Here we have investigated the mechanisms of resistance to these two insecticides by studying cross-resistance, synergism, activity of detoxifying enzymes, and possible modifications of the target proteins. Resistance to pirimicarb was shown to be mainly due to a decreased sensitivity of the target acetylcholinesterase; this modification conferred also, resistance to propoxur but not to methomyl and the two tested organophosphates (acephate and paraoxon). Endosulfan resistance was associated with a moderate level of resistance to dieldrin, and resistance to both insecticides was due, in part, to increased detoxification by glutathione S-transferases (GST). The endosulfan resistant strain displayed the same amino acid at position 302 of the Rdl gene (GABA receptor) as susceptible aphids (e.g. Ala), indicating that the Ala to Ser (or to Gly) mutation observed among dieldrin resistant strains of other insect species was not present.
ESTHER : Rufingier_1999_Insect.Biochem.Mol.Biol_29_385
PubMedSearch : Rufingier_1999_Insect.Biochem.Mol.Biol_29_385
PubMedID: 10333576