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D Eide

Publications and source records attributed to D Eide.

25 records · Page 2Linked to original sources
PubMed1992

Increased dosage of a transcriptional activator gene enhances iron-limited growth of Saccharomyces cerevisiae.

We have selected for genes that, when present in multiple copies, enhance growth of wild-type cells of Saccharomyces cerevisiae in an iron-limiting medium. A gene designated FUP1, for 'ferric utilization proficient', was isolated by this approach. Increased dosage of FUP1 reduces the concentration of iron in the medium required for efficient growth and confers elevated levels of iron uptake activity in iron-limited cells. Disruption of the FUP1 locus reduces wild-type iron uptake rates by 2-fold in cells grown on raffinose medium but has no effect on glucose-grown cells. DNA sequencing showed that FUP1 encodes a hydrophilic 43 kDa protein identical to MSN1, a gene encoding a transcriptional activator implicated in carbon source regulation. Our results suggest that FUP1/MSN1 also regulates synthesis of gene products involved in iron uptake.

Amino Acid Sequence↗
PubMed1990

Rates of condyloma and dysplasia in Papanicolaou smears with and without endocervical cells.

A retrospective study of 36,853 Papanicolaou smears recorded in our laboratory during the latter half of 1988 was undertaken to assess the effect of the absence or presence of columnar endocervical cells on the detection rate of cervical condyloma acuminatum and squamous dysplasia. We found that condyloma was diagnosed only slightly more frequently in smears with endocervical cells than in those without. However, cervical intraepithelial neoplasia was detected 2.3 times more frequently in smears with endocervical cells. The disparity in detection rate increased with higher grades of dysplasia. A significant difference in detection rate was maintained in all age groups except teenagers and patients 60 yr old and above. This suggests that smears lacking endocervical cells are less sensitive in screening for dysplasia and should be repeated when clinically appropriate.

Adolescent↗
PubMed1989

[Familial antithrombin deficiency].

When known causes of a disposition to thrombosis are discovered (e.g. antithrombin, protein C or protein S deficiency) it is important to investigate family members and inform individuals who are deficient in the factor in question. Knowledge about the cause of the thrombophilia will stimulate prophylactic efforts, and may be very important for diagnosis and treatment of the patient. A recently discovered new family with antithrombin deficiency is presented.

Adult↗
PubMed1988

Insertion and excision of Caenorhabditis elegans transposable element Tc1.

The transposable element Tc1 is responsible for most spontaneous mutations that occur in Caenorhabditis elegans variety Bergerac. We investigated the genetic and molecular properties of Tc1 transposition and excision. We show that Tc1 insertion into the unc-54 myosin heavy-chain gene was strongly site specific. The DNA sequences of independent Tc1 insertion sites were similar to each other, and we present a consensus sequence for Tc1 insertion that describes these similarities. We show that Tc1 excision was usually imprecise. Tc1 excision was imprecise in both germ line and somatic cells. Imprecise excision generated novel unc-54 alleles that had amino acid substitutions, amino acid insertions, and, in certain cases, probably altered mRNA splicing. The DNA sequences remaining after Tc1 somatic excision were the same as those remaining after germ line excision, but the frequency of somatic excision was at least 1,000-fold higher than that of germ line excision. The genetic properties of Tc1 excision, combined with the DNA sequences of the resulting unc-54 alleles, demonstrated that excision was dependent on Tc1 transposition functions in both germ line and somatic cells. Somatic excision was not regulated in the same strain-specific manner as germ-line excision was. In a genetic background where Tc1 transposition and excision in the germ line was not detectable, Tc1 excision in the soma still occurred at high frequency.

Animals↗
PubMed1985

Transposition of Tc1 in the nematode Caenorhabditis elegans.

We have identified a strain of Caenorhabditis elegans in which the transposable element Tc1 is genetically active. Most spontaneous mutations affecting the unc-54 myosin heavy chain gene of C. elegans variety Bergerac are due to insertions of Tc1 within unc-54. The Bergerac genome contains an unusually high number of Tc1 elements, but this is not responsible for transpositional activity. Another variety of C. elegans, strain DH424, contains an equally high number of Tc1 elements, but transpositions are not detected. Tc1 insertion mutations are genetically unstable. They revert to unc-54+ in both germ-line and somatic cells. Germ-line revertants are wild type and contain precise or nearly precise excisions of Tc1. Somatic revertants are genetic mosaics; they contain small patches of revertant muscle tissue in otherwise mutant animals. The pattern of mosaicism often allows us to know when and where during muscle development the excisions occur. Somatic reversion can be over 1000-fold more frequent than germ-line reversion.

Animals↗
PubMed1985

The gene structures of spontaneous mutations affecting a Caenorhabditis elegans myosin heavy chain gene.

We have isolated spontaneous mutations affecting the unc-54 major myosin heavy chain gene of Caenorhabditis elegans (variety Bristol). Spontaneous unc-54 mutants occur in C. elegans populations at a frequency of approximately 3 X 10(-7). We have studied the gene structure of 65 independent unc-54 mutations using filter-transfer hybridization techniques. Most unc-54 mutations (50 of 65) exhibit no abnormalities detected with these techniques; these mutations are small lesions affecting less than 100 base pairs. Approximately 17% of the mutations (11 of 65) are simple deletions, ranging in size from less than 100 base pairs to greater than 17 kilobases. One isolate contains two separate deletions, each of which affects unc-54. Two mutants contain tandem genetic duplications that include a portion of unc-54 and extend 8-10 kilobases beyond the 5' terminus of the mRNA. Conspicuously absent from our collection of spontaneous unc-54 mutations are any resulting from insertion of transposable genetic elements. Such mutants, if they occur, must arise at a frequency of less than 5 X 10(-9).

Animals↗