@article {49699, title = {P element-mediated in vivo deletion analysis of white-apricot: deletions between direct repeats are strongly favored.}, journal = {Genetics}, volume = {136}, year = {1994}, month = {1994 Mar}, pages = {1001-11}, abstract = {

We have isolated and characterized deletions arising within a P transposon, P[hswa], in the presence of P transposase. P[hswa] carries white-apricot (wa) sequences, including a complete copia element, under the control of an hsp70 promoter, and resembles the original wa allele in eye color phenotype. In the presence of P transposase, P[hswa] shows a high overall rate (approximately 3\%) of germline mutations that result in increased eye pigmentation. Of 234 derivatives of P[hswa] with greatly increased eye pigmentation, at least 205 carried deletions within copia. Of these, 201 were precise deletions between the directly repeated 276-nucleotide copia long terminal repeats (LTRs), and four were unique deletions. High rates of transposase-induced precise deletion were observed within another P transposon carrying unrelated 599 nucleotide repeats (yeast 2 mu FLP; recombinase target sites) separated by 5.7 kb. Our observation that P element-mediated deletion formation occurs preferentially between direct repeats suggests general methods for controlling deletion formation.

}, keywords = {Alleles, Animals, Animals, Genetically Modified, Base Sequence, Crosses, Genetic, DNA, DNA Transposable Elements, Drosophila, Eye Color, Female, Genes, Insect, Male, Molecular Sequence Data, Nucleotidyltransferases, PHENOTYPE, Recombination, Genetic, Repetitive Sequences, Nucleic Acid, Sequence Deletion, Transformation, Genetic, Transposases}, issn = {0016-6731}, author = {Kurkulos, M and Weinberg, J M and Roy, D and Mount, S M} } @article {49703, title = {Polyadenylylation in copia requires unusually distant upstream sequences.}, journal = {Proc Natl Acad Sci U S A}, volume = {88}, year = {1991}, month = {1991 Apr 15}, pages = {3038-42}, abstract = {

Retroviruses and related genetic elements generate terminally redundant RNA products by differential polyadenylylation within a long terminal repeat. Expression of the white-apricot (wa) allele of Drosophila melanogaster, which carries an insertion of the 5.1-kilobase retrovirus-like transposable element copia in a small intron, is influenced by signals within copia. By using this indicator, we have isolated a 518-base-pair deletion, 312 base pairs upstream of the copia polyadenylylation site, that is phenotypically like much larger deletions and eliminates RNA species polyadenylylated in copia. This requirement of distant upstream sequences for copia polyadenylylation has implications for the expression of many genetic elements bearing long terminal repeats.

}, keywords = {Animals, Base Sequence, Blotting, Northern, DNA Transposable Elements, Drosophila melanogaster, Eye Color, Molecular Sequence Data, Oligonucleotides, Polymerase Chain Reaction, Regulatory Sequences, Nucleic Acid, Repetitive Sequences, Nucleic Acid, RNA Processing, Post-Transcriptional, RNA, Messenger}, issn = {0027-8424}, author = {Kurkulos, M and Weinberg, J M and Pepling, M E and Mount, S M} } @article {49705, title = {Characterization of enhancer-of-white-apricot in Drosophila melanogaster.}, journal = {Genetics}, volume = {126}, year = {1990}, month = {1990 Dec}, pages = {1061-9}, abstract = {

The white-apricot (wa) allele differs from the wild-type white gene by the presence of the retrovirus-like transposable element copia within the transcription unit. Most RNAs derived from wa have 3{\textquoteright} termini within this insertion, and only small amounts of structurally normal RNA are produced. The activity of wa is reduced in trans by a semidominant mutation in the gene Enhancer-of-white-apricot (E(wa). Flies that are wa and heterozygous for the enhancer have eyes which are much lighter than the orange-yellow of wa alone while E(wa) homozygotes have white eyes. This semidominant effect on pigmentation is correlated with a corresponding decrease in white RNA having wild type structure, and flies homozygous for E(wa) have increased levels of aberrant RNAs. Three reverant alleles of E(wa) generated by reversion of the dominant enhancer phenotype with gamma radiation are noncomplementing recessive lethals, with death occurring during the larval stage. The effects on wa eye pigmentation of varying doses of the original E(wa) allele, the wild type allele, and the revertant alleles suggest that the original E(wa) allele produces a product that interferes with the activity of the wild type gene and that the revertants are null alleles. We propose that the E(wa) gene product influences the activity of the downstream copia long terminal repeat in 3{\textquoteright} end formation.

}, keywords = {Alleles, Animals, Blotting, Northern, DNA Transposable Elements, Drosophila melanogaster, Eye Color, Female, Heterozygote, Homozygote, Male, Nucleic Acid Hybridization, PHENOTYPE, Poly A, Reproduction, RNA, RNA, Messenger, Transcription, Genetic}, issn = {0016-6731}, author = {Peng, X B and Mount, S M} } @article {49707, title = {Sequence of a cDNA from the Drosophila melanogaster white gene.}, journal = {Nucleic Acids Res}, volume = {18}, year = {1990}, month = {1990 Mar 25}, pages = {1633}, keywords = {Amino Acid Sequence, Animals, Base Sequence, DNA, Drosophila melanogaster, Eye Color, genes, Molecular Sequence Data}, issn = {0305-1048}, author = {Pepling, M and Mount, S M} }