Paramecium tetraurelia strain d4-2. Paramecium tetraurelia strain d4-2

Paramecium tetraurelia has two nuclei: a germinal and a somatic nucleus. The germinal nucleus or micronucleus is diploid and is responsible for transmission of genetic information whereas the somatic nucleus or macronucleus is polyploid and is involved in gene transcription. Thus, only the micronuclei undergo meiosis in order to transfer genetic information to the new generation of organisms. The macronuclei are lost at each generation and develop anew from the micronucleus. The P. tetraurelia (strain stock d4-2) macronuclear genome has been sequenced and annotated by Genoscope in collaboration with the French National Research Organization and the French National DNA Sequencing Centre. The genome was sequenced to 13X coverage and assembled using the whole genome shotgun strategy. Close to 40,000 genes have been annotated; approximately 55% of predicted P. tetraurelia proteins have no homologues in other eukaryotic species. Analysis of the P. tetraurelia macronuclear genome revealed that this organism has undergone three whole-genome duplications through time, where many genes have been lost and many others retained. The whole genome shotgun sequence data of P. tetraurelia has been submitted to GenBank.