Macrochloroplasts, which can be produced by the imbalance expression of plastid division genes, may
act as an alternative target tissue for the transformation of foreign genes especially by particle bombardment.
This paper reports the production of stable transgenic cauliflower plants expressing cauliflower
plastid division gene, BoMinD by using PEG mediated transformation of mesophyll protoplasts. Stable
transgenic BoMinD cauliflower plants had abnormally shaped chloroplasts but these did not exhibit a
true macrochloroplast or minichloroplast phenotype. Transgene number did not relate to the expression
of the BoMinD transgene. Detection of total BoMinD by western blot suggests that the slight increase
in total BoMinD levels resulted in honey-comb or doughnut shaped chloroplasts and irregular surface
membrane chloroplasts.