To fully understand a plant's nuclear genome, scientists must also study two other genomes
found within plant cells — in the «powerhouse» mitochondria and in the photosynthesizing chloroplast organelles.
Among other things, they have seen regularly recurring platelets in each cell, which they believe are parts of chloroplasts, the organelles
within plant cells where photosynthesis takes place.
Previous attempts probably didn't work well because the
cytoplasm within plant cells has machinery that metabolizes double - stranded RNA before pests such as the Colorado potato beetle can consume it.
In his original work, Zhang was able to enlist a complex of molecules known as photosystem - I (PS - I), the tiny
structures within plant cells that carry out photosynthesis.