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Binury vectors: A binary vector should contain essentially at least one of the
borders, it should have the ability to replicate in E.coli and it should contain a selectable
marker (Armitage et al., 1988; Hood et al., 1993). In principle, a binary vector consists of
two plasmid; a plasmid that is transferred and a helper plasln~d. In the initial years it was
pBI101, and later Inany verslot?s were constructed by Beckcr et a!., (1992). Additional
information on binary vectors was provided by several authors (Jones et al., 1992; Futterer,
1995). Rcccnlly it lias been suggehted to use binary vectors that conla~~l two acparale '1'-
DNAs (Crameri el al., 1996). The log~c of tlie authors is that the antibiotic resistance
marker will be lost during subsequent generations. A helper plasmid contains the vir gene
complements that are essential for transfer of T-DNA.
Protfioiers.. Futterer (1995) reviewed the subject of promoters for genetic
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transformation of plants. In the early years of gcnetic transformation of plants,
~nvestigalors were merely interested ill showing thal integration and expression of
transgenes is a rcality 111 plants. So, initially promoters endogenous to thc T-DNA were
used. Soon 11 was observed that the promoters ibr opine synthesis were weak. Cliua and his
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collaborators (Odcll cl al., 1985) isola~ed tbc CaMV 35s promoter from turnip leaves
~nfected w~rh the Caul~flower nlosaic virus (C;IMV). This promoter was found to be many
folds stronger and resulted In constitutive expressior~ of tlie introduced genes. However.
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sub-domalns of this promoter were found to be exelling tissue specific expression (Benfey
and Chua, 1989). Since then this proliloter became an attractive candidate for plant
molecular biology research. Its fusion wit11 part of mannopine synthase (MAS) promoter
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increased the potency of this promoter (Kay et al., 1987). Valuable information can be
found in the reviews by Benfey and Chua (1989), Wang and Cutler (1995).