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P Starlinger

Publications and source records attributed to P Starlinger.

At least 37 records · Page 2Linked to original sources
PubMed1985

Structure of the sucrose synthase gene on chromosome 9 of Zea mays L.

The structure of the shrunken gene of Zea mays encoding sucrose synthase (EC 2.4.1.13) was determined by (i) sequencing the transcription unit and 1.2 kb of 5' -upstream sequences from a genomic clone, (ii) by sequencing a nearly full length cDNA clone and (iii) by determining the transcription start site by a combination of primer extension experiments with synthetic oligodeoxynucleotide primers and S1 mapping. The sucrose synthase gene is 5.4 kb long, of which 2746 bp are found in the mature mRNA. The gene is interrupted by 15 introns. The first two introns are 1 kb and 0.5 kb in length, respectively, while the other introns are much smaller. A TATA box is located 30 bp upstream from the transcription start site. Approximately 610 bp upstream of the transcription start site a direct repeat of 16 nucleotides, separated by a 4-fold repetition of the sequence GGTGG is detected. The 16-bp sequence has similarities to a sequence repeat found between two promoters of a maize zein gene also expressed in the endosperm tissue. The transposable element Ds in the mutant sh-m5933 and sh-m6233 alleles is inserted in the seventh and first intron, respectively. The genomic and cDNA clones were obtained from different maize lines. This allows the determination of polymorphic sites which are frequent in 3rd codon position and absent in 1st and 2nd codon positions. In addition, the 3' -untranslated sequence shows two duplications that may have arisen by the insertion and subsequent excision of transposable elements.

Journal Article↗
PubMed1984

Analysis of sh-m6233, a mutation induced by the transposable element Ds in the sucrose synthase gene of Zea mays.

The unstable allele sh-m6233 caused by insertion of the transposable element Ds into the sucrose synthase gene of maize, was cloned. The mutation is caused by the insertion of an 4 kb DNA segment, consisting of two identical Ds elements of 2000 bp length, of which one is inserted into the center of the other in inverted orientation. This structure is, at the level of restriction mapping and partial DNA sequencing, identical to the double Ds element found in a larger insert in the mutant allele sh-m5933. 8 bp of host DNA are duplicated upon insertion. In a revertant, a 6-bp duplication is retained.

Journal Article↗
PubMed1983

The controlling element Ds at the Shrunken locus in Zea mays: structure of the unstable sh-m5933 allele and several revertants.

We have analyzed the structure of the Shrunken (Sh) locus in a strain containing an unstable recessive mutation, sh-m5933, caused by the transposable controlling element Dissociation (Ds). We have also analyzed nine spontaneous Sh revertant alleles. The sh-m5933 allele contains a 30 kb insertion at the Sh locus, as well as a duplication that includes part of the insertion and the Sh locus sequence on the 5' side of the insertion site. The revertants continue to show Ds-mediated chromosome breakage at the Sh locus, have an intact Sh locus from which the insertion has been excised, and retain the duplication. One of the nine revertant alleles has a 2 kb deletion at the junction between the Sh locus and the insertion sequence in the duplicated segment of the locus. The revertant also shows a temporal change in the pattern of somatic chromosome breakage, implicating the junction sequence as the site of Ds-mediated chromosome breakage.

Alleles↗
PubMed1982

Genomic clones of a wild-type allele and a transposable element-induced mutant allele of the sucrose synthase gene of Zea mays L.

In an attempt to isolate the transposable genetic element Ds from Zea mays L., we cloned DNA fragments hybridizing to a cDNA clone derived from the sucrose synthase gene in a lambda vector (lambda::Zm Sh). The fragments cloned from wild-type and from the Ds-induced mutant sh-m5933 (lambda::Zm sh-m5933) share a segment 6 kb long while a contiguous segment of 15 kb of lambda::Zm sh-m5933 (mutant-derived DNA) does not hybridize to the DNA segment cloned from the wild-type. Restriction maps are given, and the junction point between the two DNA segments in the mutant clone was determined. Hybridization of DNA fragments, present in the wild-type DNA of lambda::Zm Sh, but not in the mutant clone, lambda::Zm sh-m5933, to genomic DNA of sh-m5933 showed that no part of this DNA is deleted. It cannot be said whether the DNA found in the mutant, but not in the wild-type clone, has been brought there by Ds insertion or by another Ds-dependent DNA rearrangement. The mutant-derived DNA was hybridized to genomic DNA of various maize lines digested by several restriction endonucleases. Approximately 40 bands were detected. The mutant-derived DNA contains two pairs of inverted repeats several hundred nucleotide pairs long, one of which is located at the junction to wild-type-derived DNA.

Journal Article↗
PubMed1982

Bidirectional deletions associated with IS4.

A new type of chromosomal rearrangements associated with a transposable element has been described for IS4. These rearrangements are deletions, in which the transposable element IS4 and DNA adjacent to it on either side is lost. These deletions are at least ten times more frequent in the presence of IS4, than when the element is absent from that region. The formation of bidirectional deletions is more than 1,000 times more frequent than precise excision of IS4.

Bacteriophage lambda↗
PubMed1981

The sequence of IS4.

IS-elements are devoid of easily recognizable transacting functions and exert their visible effects in the position cis only (recent reviews Calos and Miller 1980; Starlinger 1980). It has been a matter of debate, whether these elements encode functions for their own transposition. In the case of the E. coli IS-elements this could not easily be determined by genetic methods, because most of these elements are present in several copies (Saedler and Heiss 1973; Deonier et al. 1979). In the case of the IS-elements flanking transposons, evidence has recently been brought forward that these carry the transposition specificity (Rothstein et al. 1980; Kleckner 1980; Grindley 1981). IS4 is present in one copy only in several E. coli K12 strains and should, therefore, be suitable for genetic and physiological studies (Chadwell et al. 1979). It has been cloned from several sites on the E. coli chromosome in pBR322 (Klaer and Starlinger 1980). Here we report the DNA sequence of IS4 which contains an open reading frame for 442 amino acids, and of the junctions of this element with surrounding DNA at three different sites in the E. coli chromosome.

Base Sequence↗
PubMed1981

An IS4-encoded protein is synthesized in minicells.

A protein of Mr 47,000 is synthesized in Escherichia coli minicells, when these harbor a multicopy plasmid carrying IS4 in either orientation and between different flanking sequences. The protein corresponds to the sequence predicted from the known DNA sequence of IS4, as shown by partial N-terminal radiolabel protein sequence analysis. Its apparent molecular weight, however, as determined from its electrophoretic mobility in SDS polyacrylamide gels, is smaller than predicted. When compared with other plasmid-encoded proteins, the IS4-encoded protein is synthesized in minicells in small amounts. Its synthesis has not been detected in a DNA-dependent cell-free system.

Amino Acid Sequence↗
PubMed1981

Integration specificity of an artificial kanamycin transposon constructed by the in vitro insertion of an internal Tn5 fragment into IS2.

IS2 has been marked genetically by the in vitro insertion into its HindIII site of a 3.3 Kb HindIII fragment of Tn5 conferring resistance to kanamycin. The transposition of the IS2::Km, thus obtained, to lambda has been found and insertion sites were characterised. Each of ten independent IS2::Km insertions were found at the same site at 61.2% of the lambda map, always in the same orientation (orientation II relative to the xis gene). The integration sites of IS2::Km in five of the kanamycin-transducing phages were determined by DNA sequence analysis, and were found to be identical at the nucleotide level. Further transposition of IS2::Km from lambda to the bacterial chromosome was demonstrated.

Bacteriophage lambda↗
PubMed1981

Translation of Zea mays endosperm sucrose-synthase mRNA in vitro.

mRNA of 23-day-old maize endosperm was translated both in wheat germ extracts and rabbit reticulocyte lysates. A protein with an apparent molecular weight of 88,000 comigrates in dodecylsulfate/polyacrylamide electrophoresis with sucrose synthase. This protein is precipitated with an antiserum against sucrose synthase and shows the same protease digestion pattern as the enzyme. It is not synthesized with mRNA extracted from sh/sh mutant kernels lacking sucrose synthase. By these criteria, the protein is the translation product in vitro of sucrose synthase mRNA. The separation of mRNA in methylmercury-hydroxide--agarose gels and subsequent translation indicates a length of sucrose synthase mRNA of 2800 nucleotides which is compatible with the coding length necessary for a protein with a molecular weight of 88,000 plus untranslated sequences.

Animals↗
PubMed1980

A cDNA clone from Zea mays endosperm sucrose synthetase mRNA.

A cDNA clone for maize endosperm sucrose synthetase of 62o nucleotide pairs length was obtained by cloning double stranded DNA obtained from the total maize endosperm poly(A) RNA in pBR322, and identifying the appropriate clone by hybrid-promoter translation. In Southern blotting to genomic BamHI-digested DNA, a single band only of approximately 20 Kb lights up, indicating that the sucrose synthetase gene is unique, or that closely linked copies are located on this DNA fragment.

Base Composition↗
PubMed1980

IS4 is still found at its chromosomal site after transposition to galT.

IS4-DNA has been hybridized to separated DNA fragments of E. coli K12 strain M28 and to three mutants caused by transposition of IS4 to galT. The parental strain shows one band hybridizing to IS4 representing one copy of IS4 in the chromosome. The mutants have this copy retained and show in addition a second band corresponding to the IS4 copy in galT. The experiments support the hypothesis that transposition of IS4 is accompanied by replication of the element.

DNA Replication↗