Drosophila melanogaster

The transcription factor serum response factor (SRF) regulates expression of growth factor-dependent genes and muscle-specific genes in vertebrates. Homologous factors regulate differentiation of some ectodermic tissues in invertebrates. To explore the molecular basis of these different physiological functions, the functionality of human, Drosophila melanogaster and Artemia franciscana SRFs in mammalian cells has been compared in this article. D. melanogaster and, to a lesser extend, A.

9p system191 01-06-2013 34 5   Download

We have characterized a glycosylated, 31 amino-acid peptide of 4932 Da isolated from Drosophila melanogaster males. The mature peptide contains a sugar moiety of 1184 Da at a NDT consensus glycosylation site and a disulfide bond. It is synthesized in the male ejaculatory duct via a 54 amino-acid precursor containing an N-terminal signal peptide and Arg-Lys at the C-terminus which is cleaved off during maturation. The gene contains an intron of 53 bp and is localized in the cytological region 99B of the D. melanogaster genome....

9p research12 01-06-2013 41 4   Download

An earlier described CK2btes gene of Drosophila melano-gasteris shown to encode amale germline speci®c isoformof regulatory bsubunit of casein kinase 2. Western-analysis using anti-CK2btes Ig revealed CK2btes protein in Drosophila testes extract. Expression of a CK2btes± b-galactosidase fusion protein driven by the CK2btes pro-moter was found in transgenic ¯ies at postmitotic stages of spermatogenesis.

10p research12 29-04-2013 31 4   Download

Themosquito,Anopheles gambiae, is an important vector of Plasmodium falciparum malaria. Full genome analysis revealed that, as in Drosophila melanogaster,the enzyme glutathione reductase is absent inA. gambiaeand func-tionally substituted by the thioredoxin system. The key enzyme of this system is thioredoxin reductase-1, a homo-dimeric FAD-containing protein of 55.3 kDa per subunit, which catalyses the reaction NADPH + H + + thio-redoxin disulfidefiNADP + + thioredoxin dithiol.

10p tumor12 20-04-2013 31 3   Download

A Drosophila melanogaster cDNA clone (GH01916) encoding a putative 723-residue long (82 kDa) protein (CG 7415) and displaying 50% identity with mammalian cytosolic dipeptidyl aminopeptidase (DPP) III was func-tionally expressed in Schneider S2 cells. Immunocytochemi-cal studies using anti-(rat liver DPP III) Ig indicated the expression of this putative DPP III at the outer cell mem-brane and into the cytosol of transfected cells.

9p tumor12 20-04-2013 37 3   Download

Four distinct eukaryotic initiation factor 2a(eIF2a)kinases phosphorylate eIF2aat S51and regulateprotein synthesis in response to various environmental stresses. These are the hemin-regulated inhibitor (HRI), the interferon-inducible dsRNA-dependent kinase (PKR), the endoplasmic reticu-lum (ER)-resident kinase (PERK) and the GCN2 protein kinase. Whereas HRI and PKR appear to be restricted to mammalian cells, GCN2 and PERK seem to be widely distributed in eukaryotes.

14p tumor12 20-04-2013 29 4   Download

The multisubstrate deoxyribonucleoside kinase ofDroso-phila melanogaster (Dm-dNK) is sequence-related to three human deoxyribonucleoside kinases and to herpes simplex virus type-1 thymidine kinase. Dm-dNK phos-phorylates both purine and pyrimidine deoxyribonucleo-sides and nucleoside analogues although it has a preference for pyrimidine nucleosides. We performed site-directed mutagenesis on residues that, based on structural data, are involved in substrate recognition.

6p fptmusic 16-04-2013 37 3   Download

In order to understand the roles of the epoxide hydrolases (EHs) in xenobiotic biotransformation in insects, we exam-ined the induction of EHs by exogenous compounds in Drosophila melangasterthird instar larvae. Among the chemicals tested, clofibrate, a phenoxyacetate hypolipider-mics drug, increased EH activity towardscis-stilbene oxide approximately twofold in larval whole-body homogenates. The same dose of clofibrate also induced glutathione S-transferase activity.

10p fptmusic 12-04-2013 36 2   Download

Mucin type O-glycosylation is a widespread modification of eukaryotic pro-teins. The transfer of N-acetylgalactosamine to selected serine or threonine residues is catalyzed by a family of polypeptide N-acetylgalactosaminyl-transferases localized in the Golgi apparatus. The most abundant elonga-tion of O-glycans is the addition of a b1-3 linked galactose by the core-1 b1-3 galactosyltransferase (core-1b3GalT), thereby building the T-antigen or core-1 structure Gal(b1-3)GalNAc(a1-O).

11p fptmusic 11-04-2013 35 4   Download

The multisubstrate nucleoside kinase of Drosophila melanogaster(Dm-dNK) can be expressed in human solid tumor cells and its unique enzymatic properties makes this enzyme a suicide gene candidate. In the present study,Dm-dNK was stably expressed in the CCRF-CEM and H9 T-lymphoblastoid cell lines. The expressed enzyme was localized to the cell nucleus and the enzyme retained its activity.

11p fptmusic 11-04-2013 41 2   Download

TheDrosophila melanogasterdeoxyribonucleoside kinase (Dm-dNK) double mutant N45D⁄N64D was identified during a previous directed evolution study. This mutant enzyme had a decreased activity towards the natural substrates and decreased feedback inhibition with dTTP, whereas the activ-ity with 3¢-modified nucleoside analogs like 3¢-azidothymidine (AZT) was nearly unchanged.

10p fptmusic 11-04-2013 34 3   Download

Mitochondrial biogenesis is a complex and highly regulated process that requires the controlled expression of hundreds of genes encoded in two separated genomes, namely the nuclear and mitochondrial genomes. To identify regulatory proteins involved in the transcriptional control of key nuc-lear-encoded mitochondrial genes, we have performed a detailed analysis of the promoter region of theasubunit of the Drosophila melanogasterF1F0 ATP synthase complex.

11p awards 05-04-2013 42 5   Download

Eukaryotic initiation factor (eIF) 4B is part of the protein complex involved in the recognition and binding of mRNA to the ribosome. Drosophila eIF4Bis a single-copy gene that encodes two isoforms, termed eIF4B-L (52.2 kDa) and eIF4B-S (44.2 kDa), generated as a result of the alternative recognition of two polyadeynlation signals during tran-scription termination and subsequent alternative splicing of the two pre-mRNAs. Both eIF4B mRNAs and proteins are expressed during the entire embryogenesis and life cycle....

14p dell39 03-04-2013 38 4   Download

We cloned a cDNA for aDrosophila melanogasterhomo-logue ofmammalian heme oxygenase (HO) and constructed a bacterial expression system of a truncated, soluble form ofD. melanogasterHO (DmDHO). The purified DmDHO degraded hemin to biliverdin, CO and iron in the presence of reducing systems such as NADPH/cytochrome P450 reductase and sodium ascorbate, although the reaction rate was slower than that of mammalian HOs. Some properties of DmHO, however, are quite different from other known HOs.

12p dell39 03-04-2013 49 4   Download

Acetylcholine hydrolysis by acetylcholinesterase is inhi-bited at high substrate concentrations. To determine the residues involved in this phenomenon, we have mutated most of the residues lining the active-site gorge but mutating these did not completely eliminate hydrolysis. Thus, we analyzed the effect of a nonhydrolysable sub-strate analogue on substrate hydrolysis and on reactiva-tion of an analogue of the acetylenzyme.

8p dell39 03-04-2013 28 4   Download

Three point mutations R335S, L336V and V476L, distin-guish the sequence of a cytochrome P450CYP6A2 variant assumed to be responsible for 1,1,1-trichloro-2,2-bis-(4¢-chlorophenyl)ethane (DDT) resistance in theRDDT R strain ofDrosophila melanogaster. To determine the impact of each mutation on the function of CYP6A2, the wild-type enzyme (CYP6A2wt) ofCyp6a2was expressed inEscheri-chia colias well as three variants carrying a single mutation, the double mutant CYP6A2vSV and the triple mutant CYP6A2vSVL. All CYP6A2 variants were less stable than the CYP6A2wt protein. ...

8p dell39 03-04-2013 52 4   Download

We recently reported the unprecedented occurrence of a hemoglobin gene (glob1) in the fruitfly Drosophila melanogaster. Here we investigate the structure and evolution of the glob1gene in otherDrosophilaspecies. We cloned and sequencedglob1genes and cDNA fromD. pseudoobscuraand D. virilis, and identified the glob1gene sequences ofD. simulans, D. yak-uba, D. erecta, D. ananassae, D. mojavensisandD. grimshawiin the data-bases.

13p dell39 27-03-2013 39 4   Download

The deoxyhexose sugar fucose has an important fine-tuning role in regula-ting the functions of glycoconjugates in disease and development in mam-mals. The two genetic model organismsCaenorhabditis elegans and Drosophila melanogasteralso express a range of fucosylated glycans, and the nematode particularly has a number of novel forms.

13p inspiron33 26-03-2013 36 3   Download

Dipeptidyl-peptidase III (DPP III) hydrolyses small peptides with a broad substrate specificity. It is thought to be involved in a major degradation pathway of the insect neuropeptide proctolin. We report the purification and characterization of a soluble DPP III from 40 gDrosophila melanogas-ter.

9p inspiron33 26-03-2013 44 5   Download

In insects, the functional molecules responsible for the taste system are still obscure. The gene for a 28.5 kDa protein purified from taste sensilla of the blowflyPhormia reginabelongs to a gene family that includestakeout of Drosophila melanogaster. Molecular phylogenetic analysis revealed that the PhormiaTakeout-like protein is most similar to the protein encoded by a member of theDrosophila takeoutgene family, CG14661, whose expression and function have not been identified yet.

11p inspiron33 25-03-2013 42 5   Download