Abstract: A process for replicating or for replicating and expressing a sequence of interest in a plant, comprising: (i) an RNA replicon or a precursor thereof, said RNA replicon being derived from a plus-sense single stranded RNA virus and comprising at least one sequence of interest; and (ii) a helper replicon, or a precursor thereof, wherein said helper replicon is (a) incapable of systemic movement in said plant both in the presence and in the absence of said RNA replicon (i) and (b) capable of expressing in a plant one or more proteins necessary for systemic movement of said RNA replicon (i), whereby said RNA replicon (i) is capable of replicating or replicating and expressing said sequence of interest in said plant, but unable to move systemically in said plant in the absence of said one or more proteins expressed by said helper replicon (ii).

Abstract: A process of producing transgenic plants or plant cells stably transformed on a chromosome with a DNA sequence of interest and capable of expressing a function of interest from said DNA sequence of interest, said process comprising (a) providing plant cells or plants with at least two different vectors, whereby (i) said at least two different vectors are adapted to recombine with each other by site-specific recombination in said plant cells for producing a non-replicating recombination product containing said DNA sequence of interest, (ii) said at least two different vectors are adapted for integrating said DNA sequence of interest into said chromosome, (iii) said DNA sequence of interest contains sequence portions from at least two of said at least two different vectors, said sequence portions being necessary for expressing said function of interest from said DNA sequence of interest; and (b) selecting plants or plant cells expressing said function of interest.

Abstract: A process of generating transgenic plants or plant cells transformed on their plastome and being devoid of a selection marker, comprising the following steps: (a) transforming plastids of a plant or plant cell with a DNA comprising: (i) a nucleotide sequence conferring replication of said DNA in a plant cell, (ii) at least one sequence of interest, (iii) sequences flanking said at least one sequence of interest necessary for stable integration of said at least one sequence of interest into the plastid genome, and (iv) a selection marker outside of said sequences flanking said sequence(s) of interest; (b) allowing integration of said at least one sequence of interest into the plastome in the presence of selective pressure; (c) allowing loss of said selection marker sequence by releasing selective pressure; and (d) recovering cells and/or plants being genetically transformed on their plastomes and being devoid of said selection marker.

Abstract: A process for replicating or for replicating and expressing a sequence of interest in a plant, comprising: (i) an RNA replicon or a precursor thereof, said RNA replicon being derived from a plus-sense single stranded RNA virus and comprising at least one sequence of interest; and (ii) a helper replicon, or a precursor thereof, wherein said helper replicon is (a) incapable of systemic movement in said plant both in the presence and in the absence of said RNA replicon (i) and (b) capable of expressing in a plant one or more proteins necessary for systemic movement of said RNA replicon (i), whereby said RNA replicon (i) is capable of replicating or replicating and expressing said sequence of interest in said plant, but unable to move systemically in said plant in the absence of said one or more proteins expressed by said helper replicon (ii).

Abstract: A process of endowing a plant or plant cells with a trait of interest by expressing an RNA sequence of interest, said process comprising: providing plant cells or cells of said plant with a first vector and a second vector and selecting cells endowed with said trait of interest, wherein said first vector contains a first nucleotide sequence with a first segment coding, in 5? to 3? direction, for—a 5? part of said RNA sequence of interest and—a 5? part of an intron; and said second vector contains a second nucleotide sequence with a second segment coding, in 5? to 3? direction, for—a 3? part of an intron and—a 3? part of said RNA sequence of interest.

Abstract: A process for producing multicellular plants, plant organs or plant tissues transformed on their plastome by the following steps is provided: (a) altering or disrupting the function of a gene in a plastid genome for producing a selectable or recognizable phenotype; (b) separating or selecting plants or cells having plastids expressing said phenotype; (c) transforming said plastid genome of said separated or selected plant, plant organ or plant tissue with at least one transformation vector having a restoring sequence capable of restoring said function; and (d) separating or selecting said transformed plant, plant organ or plant tissue having plastids expressing said restored function.

Abstract: A process of expressing a sequence of interest in a plant, plant part, or plant cell culture, comprising: (a) providing a plant, plant part, or plant cell culture containing in cell nuclei a heterologous DNA having a sequence encoding an RNA replicon operably linked or linkable to a transcription promoter, wherein said sequence encoding an RNA replicon contains (i) sequences for replicon function of said RNA replicon, said sequences being derived from a sequence of a plant RNA virus, (ii) a sequence of interest, whereby said sequences for replicon function exhibit at selected localities of said sequences of said plant RNA virus functionconservative differences from said sequence of said plant RNA virus, said differences causing an increased frequency of replicon formation compared to an RNA replicon not exhibiting said differences; and (b) causing expression of said sequence of interest.

Abstract: A process of controlling expression of a plastome-encoded sequence of interest in a plant or in plant cells by externally applying to said plant or to said plant cells a chemical or physical control signal, wherein said control signal is adapted for interacting with an intra-plastid component of the plastid protein expression machinery and wherein expression of said sequence of interest is controlled by said control signal.

Abstract: A process of the production of a product of interest in an F1 seed obtained by a hybridization of a first and a second transgenic parental plant, said hybridization generating a genetic endowment in said F1 seed for said production by combining in said F1 seed first and second partial genetic endowments of said first and second transgenic parental plants, followed by isolating said product of interest from said F1 seed or a seedling thereof.

Abstract: A process of producing a transgenic multi-cellular plant or animal organism expressing a trait of interest and having a controlled distribution of said trait to progeny, wherein said process comprises hybridising a first multi-cellular organism or a cell thereof having a first heterologous DNA sequence comprising a first fragment of a nucleotide sequence encoding said trait of interest and a second multi-cellular organism or a cell thereof having a second heterologous DNA sequence comprising a second fragment of the nucleotide sequence encoding said trait of interest, whereby said first and said second heterologous sequences are designed such that said trait of interest arises due to RNA trans-splicing after said hybridation.

Abstract: A method of controlling a genetically-modified multi-cellular organism or a part thereof, comprising the following steps: (a) providing a multi-cellular organism or a part thereof, whereby cells of said multi-cellular organism or said part contain a heterologous nucleic acid, (b) causing expression of a I protein from said heterologous nucleic acid in at least some of said cells, wherein said protein is capable of (i) leaving a cell and entering other cells of said multi-cellular organism or a part thereof, (ii) causing expression of said protein in cells containing said heterologous nucleic acid, and optionally (iii) controlling a cellular process of interest.

Abstract: A method of controlling a genetically-modified plant, comprising (a) providing a genetically-modified plant, whereby cells of said genetically-modified plant contain a heterologous nucleic acid and whereby said genetically-modified plant is inactive with regard to a cellular process of interest, (b) switching on said cellular process of interest by directly introducing a polypeptide from a cell-free composition into cells containing said heterologous nucleic acid wherein said polypeptide and said heterologous nucleic acid are mutually adapted such that said polypeptide is capable of switching on said cellular process of interest.

Abstract: This invention provides process of amplification and/or expression of a sequence of interest in a cell by providing for generating within said cell at least one amplicon by trans-splicing between an RNA sequence designed for being capable of trans-splicing and a target RNA, whereby said amplicon is capable of amplifying in said cell and capable of expressing a sequence of interest.