Disease relevance of alpha-Est1

• Unexpectedly, ES links together non-LTR retrotransposons and single-stranded RNA viruses like influenza C and coronaviruses, which are known to depend on their own ES [1].

Psychiatry related information on alpha-Est1

• Our observations agree with previous results for D. melanogaster and provide additional support to our hypothesis that after the duplication event Est-6 retained the esterase-coding function and its role during copulation, while psiEst-6 lost that function but now operates in conjunction with Est-6 as an intergene [2].

High impact information on alpha-Est1

• Here we present the crystal structure of a Drosophila PERIOD (dPER) fragment comprising two tandemly organized PAS (PER-ARNT-SIM) domains (PAS-A and PAS-B) and two additional C-terminal alpha helices (alphaE and alphaF) [3].
• Neurotactin has a large cytoplasmic domain rich in charged residues and an extracellular domain similar to cholinesterase that lacks the active site serine required for esterase activity [4].
• The gene for the esterase S isozyme complex (estS) has been localized in band 2G5e of chromosome II [5].
• The cloning and expression of the gene encoding organ-specific esterase S from the genome of Drosophila virilis [5].
• In both cases, esterase S is synthesized in the oocytes, and the major part of the protein is transported from the oocytes and accumulated in the incubation medium [5].

Biological context of alpha-Est1

• The evolution of an alpha-esterase pseudogene inactivated in the Drosophila melanogaster lineage [6].
• The esterase amino acid sequences show 37-66% identity with one another and all but one have all the motifs characteristic of functional members of the carboxyl/cholinesterase multigene family [7].
• Molecular cloning of an alpha-esterase gene cluster on chromosome 3r of Drosophila melanogaster [8].
• The regulatory regions of homologous genes encoding esterase 6 (Est-6) of Drosophila melanogaster and esterase 5B (Est-5B) of Drosophila pseudoobscura show very little similarity [9].
• Extent of genetic variation at a highly polymorphic esterase locus in Drosophila pseudoobscura [10].

Anatomical context of alpha-Est1

• Integrins of the beta7 subfamily, alpha4 beta7 and alphaE beta7, contribute to lymphocyte homing and to the development of protective or autoreactive immune responses at mucosal sites [11].
• Finally, we show that the 64kDa protein of human semen reveals positive cross-reactivity with antibodies directed against Mytilus MAP and Drosophila esterase S [12].
• Mussel MAP, a major gonad-duct esterase-like protein, is released into sea water as a dual constituent of the seminal fluid and the spermatozoon [12].
• The present study focused on this problem and report our observations on biochemical characteristics of male-associated polypeptide (MAP) identified in the gonad tissue of bivalve molluscs, Mytilus galloprovincialis, in comparison to those of male-specific carboxylesterase (esterase S) of Drosophila virilis ejaculatory bulbs [13].
• This esterase is contained in male genitalia only, predominantly in the ejaculatory bulb (waxy plug) [14].

Associations of alpha-Est1 with chemical compounds

• Final purification was achieved by anion-exchange h.p.l.c., in the case of esterase-5 followed by gel-filtration h.p.l.c. The resultant esterase preparations were homogeneous, as judged by gel-filtration h.p.l.c., SDS/polyacrylamide-gel electrophoresis and non-denaturing gel electrophoresis [15].
• The insecticides spinosad, diazinon, nitenpyram, lufenuron and dicyclanil did not induce any P450, GST or esterase gene expression after a short exposure to high lethal concentrations of insecticide [16].
• The kinetic characteristics of the main isozymes of Drosophila virilis esterase were studied and Km values of esterase-2, -4, and -6 and p-esterase for alpha- and beta-naphthyl acetate were obtained [17].
• Juvenile hormone (JH) was shown to inhibit the p-esterase activity when in competition with beta-naphthyl acetate and the general esterase inhibitor, diisopropylphosphofluoridate (DFP), was shown to inhibit all the components of the D. virilis esterase patterns except p-esterase [17].

Other interactions of alpha-Est1

• Previous analyses of the alpha-esterase cluster of Drosophila melanogaster revealed 10 active genes and the DmalphaE4a-Psi pseudogene [6].
• Sequencing of one of the putative esterase genes in the Drosophila cluster, alpha E1, shows that it would encode features characteristic of an active carboxyl/cholinesterase, including the so-called catalytic triad, the nucleophilic elbow and oxyanion hole [8].
• Southern and Northern blot hybridization analyses of the 20-kb region surrounding the Est-6/Est-P duplication failed to detect any other duplicated esterase genes, although this region is actively transcribed [18].
• Based on the tissue distribution of these transcripts, Lc alpha E7 may possibly encode the esterase, E3, which is involved in organophosphate resistance [19].
• As anticipated, we found that a CNBr fragment derived from the N-terminal part of lamin Dm0-derivatives (amino acid residues 2-158; fragment A) was phosphorylated during both interphase and mitosis [20].

Analytical, diagnostic and therapeutic context of alpha-Est1

• PCR primers designed from the alpha-esterase gene cluster of Drosophila melanogaster have been used to isolate fragments from eight esterase genes in the Australian sheep blowfly, Lucilia cuprina [19].
• An autonomous synthesis of the S- esterase in the ejaculatory bulb was established by transplantation of imaginal genital discs into larvae of different Drosophila stocks [14].

References