RNA transformation vector

A DNA transcription vector comprising cDNA having one strand complementary to a capped RNA molecule capable of infecting a host cell, which capped RNA molecule comprises a cis-acting replication element derived from a (+) strand RNA plant virus, which capped molecule has no extraneous nonviral sequences between the cap site and the 5' terminus of the viral sequence, and which capped RNA molecule further comprises an exogenous RNA segment capable of expressing its function in a host cell in a region of said capped RNA molecule able to tolerate said segment without disrupting RNA replication of said capped RNA molecule, in the presence of trans-acting replication elements in said host cell.

A method of modifying a host plant cell, genotypically or phenotypically, which method comprises introducing into the cell a capped RNA molecule capable of infecting said host cell, wherein the capped RNA molecule comprises a cis-acting replication element derived from a (+) strand RNA plant virus, wherein the capped RNA molecule has the same capped 5' end as said virus such that there are no extraneous nonviral sequences between the cap site and the 5' terminus of the viral sequence, and wherein the capped RNA molecule further comprises an exogenous RNA segment in a region of said capped RNA molecule able to tolerate said segment without disrupting RNA replication of said capped RNA molecule in the presence of trans-acting replication elements in said host cell, whereby the exogenous RNA segment confers a detectable trait in the host cell, thereby modifying said host cell.

A capped RNA molecule capable of infecting a host plant cell, said capped RNA molecule having no extraneous nonviral sequences between the cap site and the 5' terminus of the viral sequence, said capped RNA molecule comprising:

• (a) the entire genome of a (+) strand RNA virus, said (+) strand RNA virus chosen from the group consisting of TMV, AMV and BMV, and
• (b) an exogenous RNA segment, capable of expressing its function in a host plant cell, said exogenous RNA segment inserted into said genome of a (+) strand RNA virus at a gene site chosen from the group consisting of the coat protein gene site and the 3a gene site.

A method of modifying a host plant cell, genotypically or phenotypically, which method comprises introducing to the cell a capped RNA molecule capable of infecting a host plant cell, said capped RNA molecule having no extraneous nonviral sequences between the cap site and the 5' terminus of the viral sequence, said capped RNA molecule comprising:

• (a) the entire genome of a (+) strand RNA virus, said (+) strand RNA virus chosen from the group consisting of TMV, AMV and BMV, and
• (b) an exogenous RNA segment, capable of expressing its function in a host plant cell, said exogenous RNA segment inserted into said genome of a (+) strand RNA virus at a gene site chosen from the group consisting of the coat protein gene site and the 3a gene site,
• whereby the exogenous RNA segment confers a detectable trait in the host plant cell, thereby modifying said host plant cell.

A DNA transcription vector comprising DNA having one strand complementary to a capped RNA molecule capable of infecting a host plant cell, said capped RNA molecule having no extraneous nonviral sequences between the cap site and the 5' terminus of the viral sequence, said capped RNA molecule comprising:

• (a) the entire genome of a (+) strand RNA virus, said (+) strand RNA virus chosen from the group consisting of TMV, AMV and BMV, and
• (b) an exogenous RNA segment, capable of expressing its function in a host plant cell, said exogenous RNA segment inserted into said genome of a (+) strand RNA virus at a gene site chosen from the group consisting of the coat protein gene site and the 3a gene site.