Advantages of Chloroplast Transformation
In higher plants like Nicotiana tabacumalso, transformation of chloroplast genome was successfully achieved, but with 100-fold lower efficiency than in Chlamydomonas. The plants carrying transgenic plastome are often described as transplastomic plants, which are being preferred over transgenic plants (with foreign gene transferred to the nucleus) for the following reasons: (i) Several useful genes of agronomic value reside in chloroplast genome, and are therefore suited to express efficiently in the chloroplast only.
(ii) Protein synthesis machinery in the nucleus and the cytoplasm is not suited to the transcription and translation of desirable microbial genes that are often intended to be transferred in the transgenic crops. In contrast, the protein synthesis machinery of chloroplast resembles that of prokaryotes (e.g. 70S ribosomes), so that the genes of prokaryotic origin are appropriately expressed, when transferred to a chloroplast.
