BOTANY Higher Secondary Second Year - Textbooks Online

Ti plasmid
T-DNA
Foreign DNA
Bacterial
chromosome
Plant bearing genes
for new traits
Plant cell
Foreign
DNA
Fig. 4.2. Gene transfer in plants
chromosomal position to another. Through tissue culture methods, such
plant cells are cultured, induced to multiply and differentiate to form into
plantlets. The plantlets are transplanted to soil, where they are allowed to
express the foreign gene introduced into them when they multiply and
grow in larger population.
How DNA is cut?
All bacteria produce atleast one type of restriction enzymes. They
are meant to help the recombinant researchers to enable them to cut the
DNA but to help in the very survival of the bacterial species against the
invading bacterial viruses. The restriction enzymes can chop up and render
harmless invading viral DNA.Restriction enzymes cleave DNA at very specific
places along its length. The restriction enzyme ECORI (E.coli Restriction
Enzyme I) produced by the intestinal bacterium E. coli recognizes the
following sequence.
147
T-DNA integrated into
host DNA
Transformed
plant cell
Plantlets grown in culture medium
Multiplication of
cells