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W Schuster

Publications and source records attributed to W Schuster.

At least 55 records · Page 3Linked to original sources
PubMed1990

Genes for tRNA(Gly), tRNA(His), tRNA(Lys), tRNA(Phe), tRNA(Ser) and tRNA(Tyr) are encoded in Oenothera mitochondrial DNA.

The genes coding for tRNA(Gly), tRNA(His), tRNA(Lys), tRNA(Phe), tRNA(Ser) and tRNA(Tyr) have been identified in Oenothera mitochondrial DNA. Sequence analysis of these genes and their surrounding sequences are presented and compared with other known tRNA genes from plant mitochondria. All six deduced tRNA sequences can be folded into the classical cloverleaf structure model. Only the tRNA(His) gene shows high homology with the corresponding chloroplast gene and thus appears to be derived from a transfer event of chloroplast sequences into the mitochondrial genome. The sequences surrounding this gene, however, show little similarity with the chloroplast genome. The other five deduced tRNAs display a much lower similarity with their chloroplast counterparts and thus appear to be genuine mitochondrial tRNAs. These tRNAs are highly conserved between monocots and dicots with maximally three nucleotides differing between the Oenothera sequences and their wheat homologues. A purine-rich sequence is found upstream of each tRNA gene in Oenothera, similar to wheat mitochondrial tRNA genes, that could be involved in transcription signalling.

Base Sequence↗
PubMed1990

RNA editing in the cytochrome b locus of the higher plant Oenothera berteriana includes a U-to-C transition.

RNA editing in the cytochrome b locus of Oenothera berteriana mitochondria modified a number of cytidine nucleotides to uridines, mostly altering codon identities. One nucleotide alteration involved a reverse modification changing a genomic thymidine to a cytidine in the cDNA sequence. The enzymatic editing activity in higher-plant mitochondria thus appears to be able to catalyze the interconversion of pyrimidines in both directions at specific nucleotides in the mRNA template.

Amino Acid Sequence↗
PubMed1989

RNA editing in plant mitochondria.

Comparative sequence analysis of genomic and complementary DNA clones from several mitochondrial genes in the higher plant Oenothera revealed nucleotide sequence divergences between the genomic and the messenger RNA-derived sequences. These sequence alterations could be most easily explained by specific post-transcriptional nucleotide modifications. Most of the nucleotide exchanges in coding regions lead to altered codons in the mRNA that specify amino acids better conserved in evolution than those encoded by the genomic DNA. Several instances show that the genomic arginine codon CGG is edited in the mRNA to the tryptophan codon TGG in amino acid positions that are highly conserved as tryptophan in the homologous proteins of other species. This editing suggests that the standard genetic code is used in plant mitochondria and resolves the frequent coincidence of CGG codons and tryptophan in different plant species. The apparently frequent and non-species-specific equivalency of CGG and TGG codons in particular suggests that RNA editing is a common feature of all higher plant mitochondria.

Amino Acid Sequence↗
PubMed1989

Conserved sequence elements at putative processing sites in plant mitochondria.

About 50 nucleotides are conserved in two distinct sequence elements at the 5' termini of abundant short transcripts from plant mitochondrial genes with complex transcription patterns. These sequence motifs are found in both structural RNA and protein-coding precursor transcripts, for example, upstream of the mature 26S rRNA and the shortest transcript of the ATPase subunit 9 genes in different plant species. The high degree of sequence similarity in these plant mitochondrial loci suggests a common functional significance in 5' processing site determination and selection.

Amino Acid Sequence↗
PubMed1989

[Wild domestic pigeons--a public health problem of increasing significance in East Germany].

In many cities of the GDR the number of wild house pigeons is increasing. Because of their distribution, noxious effects and hygienic importance they are considered by law as health pests. Therefore, their populations have to be regulated in such a way to minimize the noxious effects caused by them. The State Hygiene inspectorate is responsible for organization and surveillance of health pest control. At present in the GDR two procedures are allowed applying chemical substance for pest control by specialists. A catching procedure, applicable everywhere, is well proving a success. By restauration of old buildings and closing of lofts in new ones it is possible to take prophylactic measures against the increasing number of pigeons. The municipal administration should coordinate the possible measures in the respective territory.

Animal Welfare↗
PubMed1988

The NADH-dehydrogenase subunit 5 gene in Oenothera mitochondria contains two introns and is co-transcribed with the 5 S rRNA gene.

The gene encoding subunit 5 of the NADH dehydrogenase complex (ND 5) has been identified in Oenothera mitochondria from a cDNA clone. The coding region is interrupted by a type II intron of 850 nucleotides and a second intervening sequence of 357 nucleotides. Genomic sequence rearrangement within the first intron creates a nontranscribed partial copy of the gene. The intact ND 5 gene is transcribed in a complex pattern with mRNAs including the 5 S rRNA sequence. Excision of the two introns appears to proceed slowly in vivo since the steady state mitochondrial RNA contains significant proportions of unprocessed precursor molecules.

Amino Acid Sequence↗
PubMed1987

Plastid, nuclear and reverse transcriptase sequences in the mitochondrial genome of Oenothera: is genetic information transferred between organelles via RNA?

We describe an open reading frame (ORF) with high homology to reverse transcriptase in the mitochondrial genome of Oenothera. This ORF displays all the characteristics of an active plant mitochondrial gene with a possible ribosome binding site and 39% T in the third codon position. It is located between a sequence fragment from the plastid genome and one of nuclear origin downstream from the gene encoding subunit 5 of the NADH dehydrogenase. The nuclear derived sequence consists of 528 nucleotides from the small ribosomal RNA and contains an expansion segment unique to nuclear rRNAs. The plastid sequence contains part of the ribosomal protein S4 and the complete tRNA(Ser). The observation that only transcribed sequences have been found i more than one subcellular compartment in higher plants suggests that interorganellar transfer of genetic information may occur via RNA and subsequent local reverse transcription and genomic integration.

Base Sequence↗
PubMed1987

The cytochrome oxidase subunit I and subunit III genes in Oenothera mitochondria are transcribed from identical promoter sequences.

Two loci encoding subunit III of the cytochrome oxidase (COX) in Oenothera mitochondria have been identified from a cDNA library of mitochondrial transcripts. A 657-bp sequence block upstream from the open reading frame is also present in the two copies of the COX subunit I gene and is presumably involved in homologous sequence rearrangement. The proximal points of sequence rearrangements are located 3 bp upstream from the COX I and 1139 bp upstream from the COX III initiation codons. The 5'-termini of both COX I and COX III mRNAs have been mapped in this common sequence confining the promoter region for the Oenothera mitochondrial COX I and COX III genes to the homologous sequence block.

Amino Acid Sequence↗
PubMed1986

Transcript termini of messenger RNAs in higher plant mitochondria.

The 3'-termini of the mRNAs for subunit II of the cytochrome oxidase (COX II) and for the alpha-subunit of the mitochondrial ATPase (ATPA) have been determined in Oenothera mitochondria by two independent methods. Analysis of both transcripts by S1 protection experiments and of cloned cDNAs show an identical terminal 50 nucleotide sequence, to which homology is found 3' to some gene sequences in the maize mitochondrial genome. These regions can be folded into potential secondary structures similar to bacterial terminators.

DNA↗
PubMed1984

[Clinical, sonographic and radiologic findings in spinal dysraphism of the lumbosacral region].

Demonstrating the clinical, sonographic and radiologic findings in three pediatric patients suffering from caudal spinal dysraphism the various diagnostic and therapeutic problems of neural tube defects are discussed. Important conclusions are as follows: (1) Early diagnosed and operated malformations of the caudal spine may cause neurologic, neurosurgical, urogenital, gastrointestinal and orthopedic complications even after uneventful years. Mostly the reason is a prevented ascensus of the conus medullaris. Therefore a longstanding follow-up of these patients is mandatory. (2) The patient's examiners have to look for cutaneous manifestations of spinal dysraphism even in the sacral region to avoid secondary damage. (3) Sonography today is a valuable diagnostic method not only applied for screening examinations but also to establish definite diagnoses in many cases. The application of other methods is therefore guided by sonographic findings.

Child↗
PubMed1983

[Pharmacokinetic aspects of excretory urography in children].

Contrast media able to pass through the kidney were a major advance in the field of radiodiagnostics. Excretory urography is usually performed using metabolically-inactive substances which accumulate in the kidney and kidney-pelvis. A two-compartment model has always been used so far for pharmacokinetic evaluation of this. However, in doing so, the kidney pelvis was not taken in account. A further compartment was therefore added to this model which enables all the physiological processes demonstrated by excretory urography to be included in the evaluation. With this model, blood and urine levels can be used at the same time to calculate pharmacokinetic variables, as shown in 6 pediatric patients. In addition to the cumulative excretion of urine and blood levels of the contrast medium, the concentrations of the latter in the renal pelvis are shown. Particular attention is paid to the effects of two important factors in investigations using contrast medium--diuresis and total body fluid volume.

Adolescent↗