Molecular characterization of type II topoisomerase in the endosymbiont-bearing Trypanosomatid Blastocrithidia culicis.
DNA topoisomerases are involved in DNA metabolism. These enzymes are inhibited by antimicrobial and antitumoral agents and might be important targets in the chemotherapy of diseases caused by parasites. We have cloned and characterized the gene encoding topoisomerase II from the monoxenic trypanosomatid Blastocrithidia culicis (BcTOP2). The BcTOP2 gene has a 3693 nucleotide-long open reading frame that encodes a 138 kDa polypeptide. The B. culicis topoisomerase II (BctopoII) amino-acid sequence shares high similarity (>74%) with topoisomerases from other trypanosomatids, and shares a lower similarity (41%) with other eukaryotic topoisomerases II from yeast to humans. BcTOP2 is a single copy gene and encodes a 4.4 kb mRNA. Western blotting of B. culicis extracts using the antiserum raised against a C-terminal portion of BctopoII showed a 138 kDa polypeptide. Immunolocalization assays showed that the antiserum recognized the nuclear topoisomerase II.
Instituto de Biologia Molecular do Paraná, Curitiba, PR, Brasil.
Edio Elígio
EE
Lourenço
Danielle Pereira
DP
Cavalcanti
Gisele Fernanda
GF
Assine Picchi
Wanderley
W
Souza
Marco
M
Aurélio Krieger
Maria Cristina
MC
Machado Motta
Samuel
S
Goldenberg
Stenio
S
Perdigão Fragoso
D000595:Amino Acid Sequence; D000818:Animals; D002467:Cell Nucleus / Q000201:enzymology / Q000648:ultrastructure; D004250:DNA Topoisomerases, Type II / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D014351:Trypanosomatina / Q000201:enzymology* / Q000235:genetics / Q000648:ultrastructure
D004250:DNA Topoisomerases, Type II