Stress biomarkers in Ateles (Atelidae, Platyrrhini) genus

NIEVES, MARIELA; MARAÑON, DAVID G.; BAILEY, SUSAN M.; MUDRY, MARTA D.

Recife

Congreso; II Congresso Latinoamericano e XV Congresso Brasileiro de Primatologia; 2013

Platyrrhini chromosomes have been extensively studied and different rearrangements involved in their evolutionary process described. Due to the key role that telomeres play in maintaining chromosomal stability, analysis of telomere distribution is of great interest in karyotype evolution and genomic instability studies. Furthermore, fragile sites in general are reliable markers of genetic instability, so their study provides a useful tool for evaluating changes in chromosome structure with possible implications in speciation. We analyzed primary fibroblast cell cultures of animals living in captivity utilizing Fluorescence plus Giemsa (FPG) and Chromosome Orientation FISH (CO-FISH) approaches to: 1) characterize telomere status and identify spontaneously occurring rearrangements along the chromosomes of two Atelidae species: Ateles paniscus (APA) and Ateles chamek (ACH); and 2) compare the two species with respect to genomic instability and its relation to stress. Of particular note was a remarkably high level of spontaneous sister chromatid exchange (SCE) in ACH as compared to APA. Interestingly, SCE were most frequently observed in the chromosomes involved in previously described evolutionary rearrangements (# 4, 5, 6 and 7 pairs) that gave rise to the species of the genus. CO-FISH experiments confirmed that both species had the expected number of telomere signals: 64 for APA and 68 for ACH. Additionally, telomere duplications and interstitial telomere signals were observed in APA chromosomes, some of which were also associated with SCE. These preliminary results are the first description of SCE frequencies in Ateles. Our analyses support regions of Ateles chromosomes susceptible to exchange events being fragile regions and evolutionary hot spots. In the case of ACH, elevated SCE levels may reflect of an unstable genome as a consequence of a stressful environment. In conclusion, we propose that SCE analyses could provide valuable indicators of instability in Ateles.