Gene_locus Report for: drome-2vite

The fly Drosophila melanogaster is one of the most intensively studied organisms in biology and serves as a model system for the investigation of many developmental and cellular processes common to higher eukaryotes, including humans. We have determined the nucleotide sequence of nearly all of the approximately 120-megabase euchromatic portion of the Drosophila genome using a whole-genome shotgun sequencing strategy supported by extensive clone-based sequence and a high-quality bacterial artificial chromosome physical map. Efforts are under way to close the remaining gaps; however, the sequence is of sufficient accuracy and contiguity to be declared substantially complete and to support an initial analysis of genome structure and preliminary gene annotation and interpretation. The genome encodes approximately 13,600 genes, somewhat fewer than the smaller Caenorhabditis elegans genome, but with comparable functional diversity.

We have identified the site of tyrosine sulfation in an insect secretory protein, yolk protein 2 of Drosophila melanogaster. Yolk proteins were purified from [35S]sulfate-labeled flies, and yolk protein 2 was separated from yolk protein 1 and yolk protein 3 by preparative two-dimensional polyacrylamide gel electrophoresis. After digestion of yolk protein 2 with trypsin and reversed-phase high performance liquid chromatography, the sulfate label was recovered in two distinct sulfopeptides which, however, had identical NH2-terminal sequences and contained 3 tyrosine residues each. After chymotryptic digestion of the two tryptic sulfopeptides, the sulfate label was recovered in one sulfopeptide which contained a single tyrosine residue. NH2-terminal sequencing showed that this tyrosine residue corresponded to tyrosine 172 of the yolk protein 2 precursor (Hung, M.-C., and Wensink, P. C. (1983) J. Mol. Biol. 164, 487-492) in the sequence Glu-Thr-Thr-Asp-Tyr(S)-Ser-Asn-Glu-Glu. This insect tyrosine sulfation site is very similar to the known vertebrate tyrosine sulfation sites in terms of amino acid composition and secondary structure. In the accompanying paper (Friederich, E., Baeuerle, P. A., Garoff, H., Hovemann, B., and Huttner, W. B. (1988) J. Biol. Chem. 263, 14930-14938), we report on the expression of Drosophila yolk protein 2 in mouse fibroblasts and show the in vivo sulfation of tyrosine 172 by the vertebrate tyrosylprotein sulfotransferase.

Clones of genes coding for two of the yolk protein precursors from Drosophila melanogaster, YPI and YPII have been isolated. A single small intron was located in the YPII coding region at about the same position as it is found in YPI (6). The entire intergenic spacer region and most of the exon I from the YPII gene have been sequenced. The "capping" sites for both mRNAs have been determined using the S1 protection and cDNA synthesis methods. Comparison of the sequences which might be involved in transcriptional or translational control of these genes reveals for YPII a Hogness Goldberg box but no indication for a conserved sequence around-70-80 (CAT box). In contrast to YPI it resembles no significant homology to the 3' end of 18S rRNA. The first 60 amino acids of exon I from both genes share little homology except for the hydrophobic amino acids which should be involved in protein secretion.

The fly Drosophila melanogaster is one of the most intensively studied organisms in biology and serves as a model system for the investigation of many developmental and cellular processes common to higher eukaryotes, including humans. We have determined the nucleotide sequence of nearly all of the approximately 120-megabase euchromatic portion of the Drosophila genome using a whole-genome shotgun sequencing strategy supported by extensive clone-based sequence and a high-quality bacterial artificial chromosome physical map. Efforts are under way to close the remaining gaps; however, the sequence is of sufficient accuracy and contiguity to be declared substantially complete and to support an initial analysis of genome structure and preliminary gene annotation and interpretation. The genome encodes approximately 13,600 genes, somewhat fewer than the smaller Caenorhabditis elegans genome, but with comparable functional diversity.

We have identified the site of tyrosine sulfation in an insect secretory protein, yolk protein 2 of Drosophila melanogaster. Yolk proteins were purified from [35S]sulfate-labeled flies, and yolk protein 2 was separated from yolk protein 1 and yolk protein 3 by preparative two-dimensional polyacrylamide gel electrophoresis. After digestion of yolk protein 2 with trypsin and reversed-phase high performance liquid chromatography, the sulfate label was recovered in two distinct sulfopeptides which, however, had identical NH2-terminal sequences and contained 3 tyrosine residues each. After chymotryptic digestion of the two tryptic sulfopeptides, the sulfate label was recovered in one sulfopeptide which contained a single tyrosine residue. NH2-terminal sequencing showed that this tyrosine residue corresponded to tyrosine 172 of the yolk protein 2 precursor (Hung, M.-C., and Wensink, P. C. (1983) J. Mol. Biol. 164, 487-492) in the sequence Glu-Thr-Thr-Asp-Tyr(S)-Ser-Asn-Glu-Glu. This insect tyrosine sulfation site is very similar to the known vertebrate tyrosine sulfation sites in terms of amino acid composition and secondary structure. In the accompanying paper (Friederich, E., Baeuerle, P. A., Garoff, H., Hovemann, B., and Huttner, W. B. (1988) J. Biol. Chem. 263, 14930-14938), we report on the expression of Drosophila yolk protein 2 in mouse fibroblasts and show the in vivo sulfation of tyrosine 172 by the vertebrate tyrosylprotein sulfotransferase.

The yp1 and yp2 genes of Drosophila code for egg yolk proteins. Their transcription is hormone-dependent and co-ordinate. In this paper we describe the complete nucleotide sequence of the yp2 gene and of the region between these two divergently transcribed genes. We also map the mature messenger RNA on the yp2 gene sequence. We then use this information and similar information previously determined for the yp1 gene to find features common to the two genes and to the two proteins. Most features common to the nucleotide sequences flanking the two genes are consensus sequences that have been found in many other eukaryotic genes. An unusual feature common to the two genes is a potential stem-and-loop structure, which has a TATA box, a capping site, ribosomal RNA homology and then a translation initiation codon at the four successive junctions between single strands and duplexes. A second unusual common feature is a 13-nucleotide sequence that is similar to a recently proposed consensus sequence for the progesterone-receptor binding site. We speculate that the stem-and-loop structure and the conserved 13-nucleotide sequence may be involved in the co-ordinate, hormone-dependent expression of the genes. In examining features common to the two proteins we find that the sequences are 53% homologous and the predicted secondary structures are nearly identical. We propose that the conserved secondary structure is important to the oligomerization and perhaps to other activities common to these proteins.

Clones of genes coding for two of the yolk protein precursors from Drosophila melanogaster, YPI and YPII have been isolated. A single small intron was located in the YPII coding region at about the same position as it is found in YPI (6). The entire intergenic spacer region and most of the exon I from the YPII gene have been sequenced. The "capping" sites for both mRNAs have been determined using the S1 protection and cDNA synthesis methods. Comparison of the sequences which might be involved in transcriptional or translational control of these genes reveals for YPII a Hogness Goldberg box but no indication for a conserved sequence around-70-80 (CAT box). In contrast to YPI it resembles no significant homology to the 3' end of 18S rRNA. The first 60 amino acids of exon I from both genes share little homology except for the hydrophobic amino acids which should be involved in protein secretion.