Impacts of the environmental gene by copper sulphate (CuSO4) without tambaqui genome (Colossoma macropomum): differential quantification of Rex1 retrotransposable element and heterochromatic profile. Impacts of the environmental gene by copper sulfate (CuSO4) without tambaqui genome (Colossoma macropomum)

The transposable elements are known for the ability to move and integrate into the genome of the host organism. They have two classifications: class I is the class of retrotransposons that have as intermediary of the transposition the RNA, from which the cDNA is synthesized and this is inserted in the genome; Class II is composed of DNA transposons, which have as their own DNA the direct migrating DNA or being copied and inserted into the genome. The Retrotransposable Element Rex1 is a non-LTR retrotransposons of the Rex family and is found in several types of organisms. Several studies indicate that the Rex family retrotransposons have the capacity to respond to environmental stress due to contamination of water with copper. The results found in this study corroborate the hypothesis that this retrotransposon possesses a response to this type of stress in Tambaqui muscle tissue, since the chromosomal mapping, through in situ hybridization by fluorescence, showed a higher number of markings on animals that were submitted to stress and the images were quantified in FLIMA software, confirming this data through the higher coefficient of fluorescence. Furthermore, we can identify, through the heterochromatic profile, that the fish subjected to stress had an increase of heterochromatic regions in the chromosome. In the absolute quantification of the Tambaqui muscle samples from the Real - Time PCR, we also found larger numbers of copies of Rex1 in the samples that were submitted to environmental stress by copper.