New techniques in plant chloroplast division hold hope for agriculture

Ground-breaking research at the University of Leicester into the division of chloroplasts holds out hope of a safer way of genetically modifying crops, with implications for agriculture particularly in the developing world.

Using three plant types – Arabidopsis, tomato and rice – Dr Simon Geir Møller has been working with colleagues in the University of Leicester Department of Biology and at the Laboratory of Plant Molecular Biology at the Rockefeller University in New York to examine how chloroplasts divide in plants.

Chloroplasts make plants green and are important organelles of plant cells and vital for life on earth. Chloroplasts perform numerous tasks such as photosynthesis (generation of oxygen) and the production of amino acids and fatty acids. They have their own unique, and very small, genome, and are derived from bacteria.

Comparing cell division in the E. coli bacterium with the way chloroplasts divide, the research team has isolated a new component of the division machinery in Arabidopsis, AtMinE1, and they have shown that this protein represents an evolutionary conserved link between bacterial division and chloroplast division.

Dr Møller explained: “People have tried for a long time to add genes to the chloroplast genome and adapt the levels of proteins in them. You can engineer complex pathways in chloroplasts that you can’t achieve in a cell nucleus.

“The main advantage is that chloroplasts are not spread by pollen, so there is no environmental hazard in plants genetically modified in this way. In other words there wouldn’t be any cross-pollination or the development of unwanted ‘superweeds’. The gene basically dies with the plant.

“The problem is that so far this has only been done in tobacco and once in the tomato plant. Our research involves genetically controlled enlarging of the chloroplasts, so that we can blast them more efficiently with DNA attached to gold particles encoding valuable proteins followed by re-manipulation of the division process.”

The work was recently published in The Plant Journal, in a report entitled “The topological specificity factor AtMinE1 is essential for correct plastid division site placement in Arabidopsis”, by Dr Simon Geir Møller and Jodi Maple of the University of Leicester Department of Biology and Nam-Hai Chua of the Laboratory of Plant Molecular Biology, the Rockefeller University, New York.

The research team is also working with collaborators in the USA on putting vaccines into chloroplasts of plants so that they can be eaten.

The research in the laboratory of Dr Simon Geir Møller is funded by the Biotechnology and Biological Sciences Research Council, The Royal Society, The John Oldacre Foundation, The Ambrose and Ann Appelbe Trust and a HEROBC Innovation Fellowship funded by HEFCE.