Abstract: The invention provides a microcapillay hybridization chamber made of a narrow bore tubing with probe segments. Each probe segment has oligonucleotide probes covalently attached to the inner wall of the tubing and the oligonucleotide probes within each segment have identical, known sequences. Many oligonucleotide probe segments can be present within a single centimeter of tubing. The invention further provides methods for using the microcapillary hybridization chambers in hybridization assays.

Abstract: The invention relates to gene silencing as observed after integration of transgenes into plant genomes. Comparison of transcriptional gene expression between an Arabidopsis line carrying a silent transgene present in multiple copies and its mutant derivative mom1 impaired in silencing of the transgene revealed two cDNA clones which are expressed in the mutant plants, but not in the parental and not in wild type plants. Both clones are derived from the same family of transcripts referred to as TSI (Transcriptionally Silent Information). Genomic templates encoding TSI are repetitive elements with mainly pericentromeric location and conserved organization among various ecotypes. Transcriptional silencing of the genomic TSI templates is specifically released in the mutant. Transcription of TSI can be used as a marker to identify a defective silencing pathway in a plant.

Abstract: A novel process for the direct transfer of foreign genes to plant genomes is described. The novel process comprises placing a gene under the control of plant expression signals and transferring it, by contact with protoplasts without the aid of natural systems for infecting plants, direct to plant cells from which genetically transformed plants can subsequently be derived.

Abstract: The present invention relates to DNA encoding proteins contributing to recombination repair of DNA damage in plant cells. The DNA sequence comprises an open reading frame encoding a protein characterized by an amino acid sequence having a 30% or more overall identity with SEQ ID NO: 3.

Abstract: A novel process for the direct transfer of foreign genes to plant genomes is described. The novel process comprises placing a gene under the control of plant expression signals and transferring it, by contact with protoplasts without the aid of natural systems for infecting plants, direct to plant cells from which genetically transformed plants can subsequently be derived.

Abstract: A novel process for the direct transfer of foreign genes to plant genomes is described. The novel process comprises placing a gene under the control of plant expression signals and transferring it, by contact with protoplasts without the aid of natural systems for infecting plants, direct to plant cells from which genetically transformed plants can subsequently be derived.

Abstract: A novel process for the direct transfer of foreign genes to plant genomes is described. The novel process comprises placing a gene under the control of plant expression signals and transferring it, by contact with protoplasts without the aid of natural systems for infecting plants, direct to plant cells from which genetically transformed plants can subsequently be derived.

Abstract: A novel process for the direct transfer of foreign genes to plant genomes is described. The novel process comprises placing a gene under the control of plant expression signals and transferring it, by contact with protoplasts without the aid of natural systems for infecting plants, directly to plant cells from which genetically transformed plants can subsequently be derived.

Abstract: A process for the maintenance and proliferation of defective, non-infectious viruses or virus genomes, comprising mutations, i.e. deletions, substitutions, insertions and new rearrangements of the viral genes or combinations of the virus DNA with heterologous genetic material in proliferating plant material and for the regeneration of whole plants containing stably integrated into their genome said defective, non-infectious virus DNA.

Abstract: The invention describes a process for culturing proliferating aggregates of plant cells, which comprises (a) uniformly plating isolated protoplasts, or isolated cells regenerated from protoplasts, in or on an agarose-solidified culture medium, and/or (b) cutting this pretreated and solidified culture medium into segments, transferring said segments to a liquid nutrient solution and continuing culturing in both cases until the cell aggregates have attained the desired size.