title: Cryptophyte gene regulation in the kleptoplastidic, karyokleptic ciliate Mesodinium rubrum.
abstract: Photosynthesis in the ciliate Mesodinium rubrum is achieved using a consortium of cryptophyte algal organelles enclosed in its specialized vacuole. A time-series microarray analysis was conducted on the photosynthetic ciliate using an oligochip containing 15,654 primers designed from EST data of the cryptophyte prey, Teleaulax amphioxeia. The cryptophycean nuclei were transcriptionally active over 13 weeks and approximately 13.5% of transcripts in the ciliate came from the sequestered nuclei. The cryptophyte nuclei and chloroplasts could divide in the ciliate, which were loosely synchronized with host cell division. A large epigenetic modification occurred after the cryptophyte nuclei were sequestered into the ciliate. Most cryptophyte genes involved in the light and dark reactions of photosynthesis, chlorophyll assimilation, as well as in DNA methylation, were consistently up-regulated in the ciliate. The imbalance of division rate between the sequestered cryptophyte nuclei and host nuclei may be the reason for the eventual cessation of the kleptoplastidy.
authors.affiliation: Department of Biology, Kongju National University, Kongju 314-701, Republic of Korea. Electronic address: ghkim@kongju.ac.kr.
authors.forename: Gwang Hoon
authors.initials: GH
authors.lastname: Kim
authors.affiliation: Department of Biology, Kongju National University, Kongju 314-701, Republic of Korea.
authors.forename: Ji Hee
authors.initials: JH
authors.lastname: Han
authors.affiliation: Department of Biology, Kongju National University, Kongju 314-701, Republic of Korea.
authors.forename: Bora
authors.initials: B
authors.lastname: Kim
authors.affiliation: Converging Research Division, National Marine Biodiversity Institute of Korea, Seocheon 325-902, Republic of Korea.
authors.forename: Jong Won
authors.initials: JW
authors.lastname: Han
authors.affiliation: Department of Biology, Chungnam National University, Daejeon 305-764, Republic of Korea.
authors.forename: Seung Won
authors.initials: SW
authors.lastname: Nam
authors.affiliation: Department of Biology, Chungnam National University, Daejeon 305-764, Republic of Korea.
authors.forename: Woongghi
authors.initials: W
authors.lastname: Shin
authors.affiliation: Southwest Sea Fisheries Research Institute, National Fisheries Research & Development Institute, Yeosu 556-823, Republic of Korea.
authors.forename: Jong Woo
authors.initials: JW
authors.lastname: Park
authors.affiliation: Department of Oceanography, Kunsan National University, Gunsan 573-701, Republic of Korea.
authors.forename: Wonho
authors.initials: W
authors.lastname: Yih
mesh_terms: D048750:Cell Nucleus Division / Q000235:genetics; D002734:Chlorophyll / Q000378:metabolism; D016798:Ciliophora / Q000235:genetics*; D044785:Cryptophyta / Q000235:genetics*; D044127:Epigenesis, Genetic; D005786:Gene Expression Regulation; D010788:Photosynthesis / Q000502:physiology
chemical_list: D002734:Chlorophyll
keywords: Endosymbiosis; Karyoklepty; Kleptoplastidy; Mesodinium rubrum; Teleaulax amphioxeia