title: The largest subunit of the RNA polymerase II of Trypanosoma cruzi lacks the repeats in the carboxy-terminal domain and is encoded by several genes.
abstract: The largest subunit of eukaryotic RNA polymerase II (RNA Pol II) of several members of Kinetoplastida order and other early diverging eukaryote contains a serine, tyrosine and proline-rich domain in the carboxyl-terminal instead of the typical heptapeptides repeats found in most eukaryotes. The lack of these repeats seems to reflect the different control of gene transcription found in these organisms. To provide further understanding in these mechanisms, we have characterized the largest subunit of RNA polymerase II (RNA Pol II LSU) in Trypanosoma cruzi. We found that it also lacks the heptapeptide repeats in the carboxy-terminal domain, but is quite similar to the same region in the Trypanosoma brucei enzyme, suggesting a conserved role for this domain. In addition, we found several genes encoding the RNA Pol II in T. cruzi, distributed in different chromosomal bands in several isolates. Two of these genes were entirely sequenced and shown to be quite similar. The presence of several gene copies of the RNA Pol II LSU, also described in African trypanosomes might reflect a gene amplification requirement that appeared early in the evolution of these organisms.
authors.affiliation: Departamento de Microbiologia, Imunologia e Parasitologia Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil.
authors.forename: Tatiana Flank
authors.initials: TF
authors.lastname: Ejchel
authors.forename: Marcel Ivan
authors.initials: MI
authors.lastname: Ramirez
authors.forename: Nancy
authors.initials: N
authors.lastname: Vargas
authors.forename: Evania Barbosa
authors.initials: EB
authors.lastname: Azevedo
authors.forename: Maria Carolina
authors.initials: MC
authors.lastname: Elias
authors.forename: Bianca
authors.initials: B
authors.lastname: Zingales
authors.forename: Sergio
authors.initials: S
authors.lastname: Schenkman
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D018628:Gene Dosage; D005786:Gene Expression Regulation; D008969:Molecular Sequence Data; D015800:Protozoan Proteins / Q000235:genetics; D012319:RNA Polymerase II / Q000737:chemistry* / Q000235:genetics*; D017422:Sequence Analysis, DNA; D020080:Tandem Repeat Sequences / Q000235:genetics*; D014158:Transcription, Genetic; D014349:Trypanosoma cruzi / Q000201:enzymology* / Q000235:genetics*
chemical_list: D015800:Protozoan Proteins; D012319:RNA Polymerase II