Chloroplast

The green, chlorophyll-containing organelle of plant (algal) cells where photosynthesis takes place. It contains several rings of DNA that are transcribed and translated. The chloroplast genome of higher plants encodes about 60 to 80 proteins. Other plastid proteins (about 3,500) are imported from the cytosol and some of the proteins are under the control of the nucleus and the chloroplast genome. The division of the chloroplast DNA follows a mechanism similar to that of the prokaryotic nucleoid. Although plastid and nuclear divisions can be uncoupled, the cell cycle and plastid divisions are coordinated for normal development (Reynaud C et al 2005 Proc Natl Acad Sci USA 102:8216). chloroplasts, chloroplast genetics, evolution of organelles, Cdt1; Osteryoung KW, McAndrew RS 2001 Annu Rev Plant Physiol Plant Mol Biol 52:315.