title: A PIWI homolog is one of the proteins expressed exclusively during macronuclear development in the ciliate Stylonychia lemnae.
abstract: In the course of macronuclear differentiation in spirotrichous ciliates massive DNA reorganization processes take place, which include splicing, cutting, rearranging and eliminating specific DNA sequences. In order to identify genes involved in these processes we took advantage of suppression subtractive hybridization. We have identified three transcripts that are exclusively expressed during macronuclear development in the ciliate Stylonychia lemnae. Two of the three differentially expressed mRNAs we have analyzed encode for novel proteins. One gene, mdp1 [macronuclear development protein 1 (MDP1)], encodes a homolog of the PIWI protein family. PIWI proteins are involved in germline differentiation processes and RNA silencing in worms, flies, mice, humans and in plants. Possible functions of the S.lemnae PIWI related protein MDP1 in the regulation of macronuclear development will be discussed.
authors.affiliation: Institute of Cell Biology, University Witten/Herdecke, Stockumer Strasse 10, 58453 Witten, Germany.
authors.forename: Christian P
authors.initials: CP
authors.lastname: Fetzer
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Hogan
authors.forename: Hans J
authors.initials: HJ
authors.lastname: Lipps
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002454:Cell Differentiation; D002467:Cell Nucleus / Q000235:genetics* / Q000648:ultrastructure; D016798:Ciliophora / Q000235:genetics* / Q000378:metabolism / Q000648:ultrastructure; D017125:Genes, Protozoan; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D015800:Protozoan Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*; D016053:RNA, Protozoan / Q000096:biosynthesis; D017386:Sequence Homology, Amino Acid
chemical_list: D015800:Protozoan Proteins; D016053:RNA, Protozoan