(Below N is a link to NCBI taxonomic web page and E link to ESTHER at designed phylum.) > cellular organisms: NE > Eukaryota: NE > Opisthokonta: NE > Metazoa: NE > Eumetazoa: NE > Bilateria: NE > Protostomia: NE > Ecdysozoa: NE > Panarthropoda: NE > Arthropoda: NE > Mandibulata: NE > Pancrustacea: NE > Hexapoda: NE > Insecta: NE > Dicondylia: NE > Pterygota: NE > Neoptera: NE > Paraneoptera: NE > Hemiptera: NE > Sternorrhyncha: NE > Aphidomorpha: NE > Aphidoidea: NE > Aphididae: NE > Aphidinae: NE > Macrosiphini: NE > Sitobion: NE > Sitobion avenae: NE
LegendThis sequence has been compared to family alignement (MSA) red => minority aminoacid blue => majority aminoacid color intensity => conservation rate title => sequence position(MSA position)aminoacid rate Catalytic site Catalytic site in the MSA MDQWLLWFGYLVASTYGLSLRHARHQSVGTPTVEEILEPQILIEDTDHVF RQRASDMFAQEPEYTEKRNLNHRRRSEFSGNQDNDFESSGETYSAYKSDD PLVIHTNKGKIRGITQAASSGKLVDAWLGIPYAKKPIGDLRFRHPRPIDR WDKTSPETILNCTTPPNTCVQIFDTLFGDFPGATMWNPNSPVSEDCLYIN VVVPKLRPQNAAVVVWIFGGGFYSGSATLDIYDPKVLVSEENVILVSMQY RVASLGFLYFDTEDVPGNAGLFDQLMALQWVHENIKLFGGNPNNVTLFGE SAGAVSVSLHLLSPLSRNLFNQAIMESGSSTAPWAILSREESYNRGLKLA KAMGCPDDRNAIHKTVECLRKVNSSAMVEKEWDHVAICFFPFVPVVDGAF LDDYPQKSLSTNNFKKTNILMGSNSEEGYYSIFYYLTELFKKEENVVVSR ENFVKAIGQLNPNADAAVKSAIEFEYTDWFSPNDPEKNRNALDKMVGDYQ FTCNVNEFAHKYALTGNNVYMYYFKHRSLNNPWPKWTGVMHGDEISYVFG DPLNPNKRYEIEEIELSKKMMRYWTNFAKTGNPSKTFEGSWVTPKWPVHT AYGKEFLTLDTNNTSIGVGPRLEQCAFWKNYVPDLTAISKSMKSDKNCTT ISGGTKTNMIKLSLWTIVMTTAVLVL
References
Title: Resistance mechanisms and associated mutations in acetylcholinesteras genes in Sitobion avenae (Fabricius) Chen M, Han Z, Qiao X, Qu M Ref: Pesticide Biochemistry and Physiology, 87:189, 2007 : PubMed
Wheat aphid, Sitobion avenae (fabricius), is one of the most important wheat pests and has been reported to be resistant to commonly used insecticides in China. To determine the resistance mechanism, the resistant and susceptible strains were developed in laboratory and comparably studied. A bioassay revealed that the resistant strain showed high resistance to pirimicarb (RR: 161.8), moderate reistance to omethoate (32.5) and monocrotophos (33.5), and low resistance to deltamethrin (6.3) and thiodicarb (5.5). A biochemistry analysis showed that both strains had similar glutathione-S-transferase (GST) activity, but the resistant strain had 3.8-fold higher esterase activity, and its AChE was insensitive to this treatment. The I50 increased by 25.8-, 10.7-, and 10.4-folds for pirimicarb, omethoate, and monocrotophos, respectively,
demonstrating that GST had not been involved in the resistance of S. avenae.
The enhanced esterase contributed to low level resistance to all the insecticides tested, whereas higher resistance to pirimicarb, omethoate,
and monocrotophos mainly depended on AChE insensitivity. However, the AChE of the resistant strain was still sensitive to thiodicarb (1.7-fold). Thus, thiodicarb could be used as substitute for control of the resistant S. avenae in this case. Furthermore, the two different AChE genes cloned from different resistant and susceptible individuals were also compared. Two mutations, L436(336)S in Sa.Ace1 and W516(435)R in Sa.Ace2, were found consistently associated with the insensitivity of AChE. They were thought to be the possible resistance mutations,
but further work is needed to confirm this hypothesis.
Title: Cloning and sequence analysis of 2 different acetylcholinesterase genes in Rhopalosiphum padi and Sitobion avenae Chen M, Han Z Ref: Genome, 49:239, 2006 : PubMed
Two genes encoding different acetylcholinesterases (AChE) were successfully cloned from 2 species of aphid, Rhopalosiphum padi (L.) and Sitobion avenae (F.). They were named Rp.AChE1 (GenBank accession No. AY707318), Rp.AChE2 (AY667435), Sa.AChE1 (AY707319), and Sa.AChE2 (AY819704), and were 2133, 2363, 2131, and 2362 bp in length and encoded 664, 676, 664, and 676 amino acids, respectively. All of them shared the characteristics of the AChE family: catalytic tiads, 3 intra-chain disulfide bridges, an acyl pocket, and the conservative aromatic residues for the active site of the gorge. Sequence analysis revealed that Rp.AChE1 and Sa.AChE1 showed higher identity to the reported orthologous genes of Drosophila AChE, and Rp.AChE2 and Sa.AChE2 to paralogous genes. However, in each of the aphids, the 2 genes from the same species shared only 29% identity between one another. It was therefore concluded that each of the aphids has 2 different AChE genes, which are either orthologous or paralogous to Drosophila AChE. The high conservation of AChE1 and AChE2 indicated that 2 acetylcholinesterases exist popularly and that both might function in aphids.
