Chloroplasts Divide by Contraction of a Bundle of Nanofilaments Consisting of Polyglucan

Abstract

Chloroplast Division Machinery The machinery for photosynthesis, which captures the Sun's energy to generate carbohydrates, generally resides in subcellular chloroplasts of plant cells. Chloroplasts must divide as the plant cell divides, but to do so requires their own plastid dividing machinery. Yoshida et al. (p. 949 : see the cover) have now analyzed the plastid dividing machinery of the single-celled alga Cyanidioschyzon merolae , whose cells each contain a single chloroplast. The plastid dividing machinery is made up of polysaccharide chains and the proteins that make them, which together generate a ring that constricts to physically divide the chloroplast.