Characterization of a Trypanosoma cruzi specific nuclear repeated sequence

Area of Science:

• Genetics
• Molecular Biology
• Parasitology

Background:

• Trypanosoma cruzi is a protozoan parasite responsible for Chagas disease.
• Understanding the genomic structure of T. cruzi is crucial for developing control strategies.
• Repetitive DNA elements can play significant roles in genome evolution and gene regulation.

Purpose of the Study:

• To isolate and characterize novel repeated DNA sequences in the Trypanosoma cruzi genome.
• To determine the distribution and conservation of this repeated sequence within T. cruzi and related species.
• To investigate the expression of the identified repeated sequence in parasite life stages.

Main Methods:

• Screening of a T. cruzi genomic library to identify repeated sequences.
• Southern blot analysis to assess sequence distribution and copy number.
• Northern blot analysis to detect homologous transcripts.

Main Results:

• Isolation of three clones containing a common, non-tandemly repeated DNA sequence.
• The sequence is dispersed across multiple chromosomes and conserved in all tested T. cruzi strains.
• The element is absent in other Kinetoplastida species, indicating T. cruzi specificity.
• The sequence size is approximately 10-12 kb with a copy number of 220 in the Dm 28c strain.
• A transcript homologous to the sequence was detected in epimastigote forms.

Conclusions:

• A novel, conserved, and dispersed repeated DNA element has been identified in Trypanosoma cruzi.
• This element represents a unique genetic marker for T. cruzi.
• The presence of a transcript suggests a potential functional role for this sequence in the parasite's biology.