title: Cloning and characterization of the gene encoding Trypanosoma cruzi DNA topoisomerase II.
abstract: The gene encoding Trypanosoma cruzi type II topoisomerase (TcTOP2) was isolated from a genomic library with a heterologous probe corresponding to part of the Trypanosoma brucei type II topoisomerase (TBrTOP2) gene. Nucleotide sequencing of TcTOP2 showed that the gene consists of an open reading frame of 3696 nucleotides (1232 amino acids), predicting a polypeptide product of 138,413 Da. Comparison of the amino acid sequence with that of type II topoisomerases from T. brucei (TBrTOP2) and Crithidia fasciculata (CfaTOP2), shows a high degree of conservation with estimated identities of 78% and 69%, respectively. TcTOP2 is a single copy gene in the genome of T. cruzi Dm28c and is expressed as a 4.5-kb mRNA. PCR mapping showed two distinct mini-exon addition sites at positions 225 and 203 upstream from the initiator AUG.
authors.affiliation: Fundação Oswaldo Cruz, Dept. Bioquímica e Biologia Molecular, Laboratório de Expressão Gênica, Rio de Janeiro, Brazil.
authors.forename: S P
authors.initials: SP
authors.lastname: Fragoso
authors.forename: S
authors.initials: S
authors.lastname: Goldenberg
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D003001:Cloning, Molecular; D016831:Crithidia fasciculata / Q000201:enzymology / Q000235:genetics; D015342:DNA Probes; D004250:DNA Topoisomerases, Type II / Q000737:chemistry / Q000235:genetics*; D016054:DNA, Protozoan / Q000737:chemistry*; D005091:Exons; D015723:Gene Library; D017125:Genes, Protozoan; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D016366:Open Reading Frames; D015183:Restriction Mapping; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D014346:Trypanosoma brucei brucei / Q000201:enzymology / Q000235:genetics; D014349:Trypanosoma cruzi / Q000201:enzymology / Q000235:genetics*
chemical_list: D015342:DNA Probes; D016054:DNA, Protozoan; D004250:DNA Topoisomerases, Type II