Functional genomic analysis of the 61D-61F region of the third chromosome of Drosophila melanogaster

Assigning functional significance to completed genome sequences is one of the next challenges in biological science. Conventional genetic tools such as deficiency chromosomes help assign essential complementation groups to their corresponding genes. We describe an F2 genetic screen to identify lethal mutations within cytogenetic region 61D-61F of the third chromosome of Drosophila melanogaster. One hundred sixteen mutations were identified by their failure to complement both Df(3L)bab-PG and Df(3L)3C7. These alleles were assigned to 14 complementation groups and 9 deficiency intervals. Complementation groups were ordered using existing deficiencies, as well as new deficiencies generated in this study. With the aid of the genomic sequence, genetic and physical maps in the region were correlated by use of PCR to localize the breakpoints of deficiencies within a 268-kb genomic contig (GenBank accession No. AC005847). Six essential complementation groups were assigned to specific genes, including genes encoding a porphobilinogen deaminase and a Sac1-like protein.Key words: Drosophila, functional genomics, porphobilinogen deaminase, synaptojanin.

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A Cluster of Cuticle Protein Genes of Drosophila melanogaster at 65A: Sequence, Structure and Evolution

Genetics ◽

10.1093/genetics/147.3.1213 ◽

1997 ◽

Vol 147 (3) ◽

pp. 1213-1224

Author(s):

Jean-Philippe Charles ◽

Carol Chihara ◽

Shamim Nejad ◽

Lynn M Riddiford

Keyword(s):

Drosophila Melanogaster ◽

Genomic Dna ◽

Multiple Copy ◽

Sequence Structure ◽

Coding Regions ◽

The Third ◽

Genetic Complexity ◽

Genes Encoding ◽

Cuticle Protein ◽

Cuticle Proteins

A 36-kb genomic DNA segment of the Drosophila melanogaster genome containing 12 clustered cuticle genes has been mapped and partially sequenced. The cluster maps at 65A 5-6 on the left arm of the third chromosome, in agreement with the previously determined location of a putative cluster encompassing the genes for the third instar larval cuticle proteins LCP5, LCP6 and LCP8. This cluster is the largest cuticle gene cluster discovered to date and shows a number of surprising features that explain in part the genetic complexity of the LCP5, LCP6 and LCP8 loci. The genes encoding LCP5 and LCP8 are multiple copy genes and the presence of extensive similarity in their coding regions gives the first evidence for gene conversion in cuticle genes. In addition, five genes in the cluster are intronless. Four of these five have arisen by retroposition. The other genes in the cluster have a single intron located at an unusual location for insect cuticle genes.

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Cytogenetic definition and morphogenetic analysis of Delta, a gene affecting neurogenesis in Drosophila melanogaster.

Genetics ◽

10.1093/genetics/118.2.235 ◽

1988 ◽

Vol 118 (2) ◽

pp. 235-245

Author(s):

A K Alton ◽

K Fechtel ◽

A L Terry ◽

S B Meikle ◽

M A Muskavitch

Keyword(s):

Nervous System ◽

Drosophila Melanogaster ◽

Genetic Analysis ◽

Inverse Correlation ◽

Small Interval ◽

Genetic Analyses ◽

The Third ◽

Complementation Groups ◽

Definition Of ◽

Morphogenetic Analysis

Abstract We have conducted a genetic analysis of a small interval of the third chromosome known to include Delta (Dl), a locus that affects the segregation of the ectoderm into neural and epidermal lineages during embryogenesis and the morphogenesis of some ectodermally derived structures, in Drosophila melanogaster. This analysis has led to the definition of seven independent complementation groups, one of which is Delta, within the interval extending from 91F6-13 to 92A2. Among the extant mutations in these seven loci, only mutations in Dl lead to the so-called neurogenic phenotype: hypertrophy of the nervous system and reduction of the epidermis. Combined cytogenetic and genetic analyses allow us to define absolute proximal (91F5-92A1) and distal (92A2) cytogenetic limits for the Dl locus. We have isolated hypomorphic and amorphic alleles of Dl and find that, for any given allele, there is an inverse correlation between neural hypertrophy and epidermal reduction in embryos and a direct correlation between the severity of embryonic phenotypes in mutant homozygotes and hemizygotes and the imaginal phenotype in heterozygous adults.

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P-Element Insertion Alleles of Essential Genes on the Third Chromosome of Drosophila melanogaster Correlation of Physical and Cytogenetic Maps in Chromosomal Region 86E-87F

Genetics ◽

10.1093/genetics/147.4.1697 ◽

1997 ◽

Vol 147 (4) ◽

pp. 1697-1722 ◽

Cited By ~ 1

Author(s):

Peter Deák ◽

Mahmoud M Omar ◽

Robert D C Saunders ◽

Margit Pál ◽

Orbán Komonyi ◽

...

Keyword(s):

Drosophila Melanogaster ◽

Genetic Maps ◽

P Element ◽

Drosophila Genome ◽

Induced Mutations ◽

Lethal Mutant ◽

P Elements ◽

Element Insertion ◽

The Third ◽

Complementation Groups

Abstract We have established a collection of 2460 lethal or semi-lethal mutant lines using a procedure thought to insert single P elements into vital genes on the third chromosome of Drosophila melanogaster. More than 1200 randomly selected lines were examined by in situ hybridization and 90% found to contain single insertions at sites that mark 89% of all lettered subdivisions of the Bridges' map. A set of chromosomal deficiencies that collectively uncover ~25% of the euchromatin of chromosome 3 reveal lethal mutations in 468 lines corresponding to 145 complementation groups. We undertook a detailed analysis of the cytogenetic interval 86E-87F and identified 87 P-element-induced mutations falling into 38 complementation groups, 16 of which correspond to previously known genes. Twenty-one of these 38 complementation groups have at least one allele that has a P-element insertion at a position consistent with the cytogenetics of the locus. We have rescued P elements and flanking chromosomal sequences from the 86E-87F region in 35 lines with either lethal or genetically silent P insertions, and used these as probes to identify cosmids and P1 clones from the Drosophila genome projects. This has tied together the physical and genetic maps and has linked 44 previously identified cosmid contigs into seven “super-contigs” that span the interval. STS data for sequences flanking one side of the P-element insertions in 49 lines has identified insertions in the αγ element at 87C, two known transposable elements, and the open reading frames of seven putative single copy genes. These correspond to five known genes in this interval, and two genes identified by the homology of their predicted products to known proteins from other organisms.

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