The genome sequence and gene models of Tetrahymena thermophila were not determined by the Joint Genome Institute (JGI), but were downloaded from NCBI on May 31, 2018. In order to allow comparative analyses with other genomes sequenced by the JGI, a copy of this genome is incorporated into the JGI Genome Portal. JGI tools were used to automatically annotate predicted proteins. Please note that this copy of the genome is not maintained by NCBI and is therefore not automatically updated.
The following text comes from NCBI Genome:
Tetrahymena thermophila
Tetrahymena thermophila is a free-swimming unicellular protist. This freshwater organism inhabits streams, lakes, and ponds. Like other ciliates, Tetrahymena cells have a complex genome structure. Each cell contains a diploid micronucleus (mic) and a somatic macronucleus (mac).The two nuclei function independently and have distinct functions and chromosomal arrangements. The mic is organized into 5 pairs of chromosomes and undergoes mitotic and meiotic division but is not transcribed. In contrast, during the formation of the mac, these chromosomes undergo site-specific fragmentation into approximately 200-300 chromosomes ranging in size from 21 kb to >3000 kb to which telomeric ends are added de novo. During this process, approximately 10% of the genome is removed. Mac chromosomes are amplified to a ploidy of approximately 45 copies except for the 21 kb ribosomal DNA minichromosome which is amplified to ~9000 copies. Transcription and translation occur in the macronucleus. T. thermophila is used in bioassays and has potential for industrial protein synthesis and biocontrol of diseases caused by related organisms.
Genome Reference(s)
Eisen JA, Coyne RS, Wu M, Wu D, Thiagarajan M, Wortman JR, Badger JH, Ren Q, Amedeo P, Jones KM, Tallon LJ, Delcher AL, Salzberg SL, Silva JC, Haas BJ, Majoros WH, Farzad M, Carlton JM, Smith RK Jr, Garg J, Pearlman RE, Karrer KM, Sun L, Manning G, Elde NC, Turkewitz AP, Asai DJ, Wilkes DE, Wang Y, Cai H, Collins K, Stewart BA, Lee SR, Wilamowska K, Weinberg Z, Ruzzo WL, Wloga D, Gaertig J, Frankel J, Tsao CC, Gorovsky MA, Keeling PJ, Waller RF, Patron NJ, Cherry JM, Stover NA, Krieger CJ, del Toro C, Ryder HF, Williamson SC, Barbeau RA, Hamilton EP, Orias E
Macronuclear genome sequence of the ciliate Tetrahymena thermophila, a model eukaryote.
PLoS Biol. 2006 Sep;4(9):e286. doi: 10.1371/journal.pbio.0040286