Editing Chloroplast (section)

===== Dinophytes =====
[[File:Ceratium furca.jpg|thumb|''[[Ceratium furca]]'', a [[peridinin]]-containing dinophyte.<ref>{{cite journal  |vauthors=Meeson BW, Chang SS, Sweeney BM |doi=10.1515/botm.1982.25.8.347 |title=Characterization of Peridinin-Chlorophyll α-Proteins from the Marine Dinoflagellate Ceratium furca |year=1982 |journal=Botanica Marina |volume=25 |issue=8 |pages=347–50|bibcode=1982BoMar..25..347M |s2cid=83867103 }}</ref>]]

The [[dinoflagellates]] are yet another very large and diverse group, around half of which are at least partially photosynthetic (i.e. [[Mixotroph|mixotrophic]]).<ref name="Campbell-2009f" /><ref name="Hackett-2004">{{cite journal | vauthors=Hackett JD, Anderson DM, Erdner DL, Bhattacharya D | title=Dinoflagellates: a remarkable evolutionary experiment | journal=American Journal of Botany | volume=91 | issue=10 | pages=1523–34 | date=October 2004 | pmid=21652307 | doi=10.3732/ajb.91.10.1523 }}</ref> Dinoflagellate chloroplasts have relatively complex history. Most dinoflagellate chloroplasts are secondary [[red algae|red algal]] derived chloroplasts. Many dinoflagellates have lost the chloroplast (becoming nonphotosynthetic), some of these have replaced it though ''tertiary'' endosymbiosis.<ref name="Dorrell-2011">{{cite journal | vauthors=Dorrell RG, Smith AG | title=Do red and green make brown?: perspectives on plastid acquisitions within chromalveolates | journal=Eukaryotic Cell | volume=10 | issue=7 | pages=856–68 | date=July 2011 | pmid=21622904 | pmc=3147421 | doi=10.1128/EC.00326-10 }}</ref> Others replaced their original chloroplast with a [[green algae|green algal]] derived chloroplast.<ref name="Keeling-2004" /><ref name="Keeling-2010" /><ref name="Hackett-2004" /> The peridinin chloroplast is thought to be the dinophytes' "original" chloroplast,<ref name="Hackett-2004" /> which has been lost, reduced, replaced, or has company in several other dinophyte lineages.<ref name="Keeling-2010" />

The most common dinophyte chloroplast is the [[peridinin]]-type chloroplast, characterized by the [[carotenoid]] pigment [[peridinin]] in their chloroplasts, along with [[chlorophyll a|chlorophyll ''a'']] and [[chlorophyll c2|chlorophyll ''c''<sub>2</sub>]].<ref name="Keeling-2004" /><ref name="Hackett-2004" /> Peridinin is not found in any other group of chloroplasts.<ref name="Hackett-2004" /> The peridinin chloroplast is bounded by three membranes (occasionally two),<ref name="Kim-2009" /> having lost the red algal endosymbiont's original cell membrane.<ref name="Keeling-2004" /><ref name="Keeling-2010" /> The outermost membrane is not connected to the endoplasmic reticulum.<ref name="Kim-2009" /><ref name="Hackett-2004" /> They contain a [[pyrenoid]], and have triplet-stacked thylakoids. Starch is found outside the chloroplast.<ref name="Kim-2009" /> Peridinin chloroplasts also have DNA that is highly [[genome reduction|reduced]] and fragmented into many small circles.<ref name="Hackett-2004" /> Most of the genome has migrated to the nucleus, and only critical photosynthesis-related genes remain in the chloroplast. 

Most dinophyte chloroplasts contain form II RuBisCO, at least the [[photosynthetic pigments]] [[chlorophyll a|chlorophyll ''a'']], [[chlorophyll c2|chlorophyll ''c<sub>2</sub>'']], [[beta-carotene|''beta''-carotene]], and at least one dinophyte-unique [[xanthophyll]] ([[peridinin]], [[dinoxanthin]], or [[diadinoxanthin]]), giving many a golden-brown color.<ref name="Janouškovec-2017" /><ref name="Hackett-2004" /> All dinophytes store starch in their cytoplasm, and most have chloroplasts with thylakoids arranged in stacks of three.<ref name="Kim-2009" />