Repetitive Sequence Distribution on Saguinus, Leontocebus and Leontopithecus Tamarins (Platyrrhine, Primates) by Mapping Telomeric (TTAGGG) Motifs and rDNA Loci

Abstract

Tamarins are a distinct group of small sized New World monkeys with complex phylogenetic relationships and poorly studied cytogenetic traits. In this study, we applied molecular cytogenetic analyses by fluorescence in situ hybridization with probes specific for telomeric sequences and ribosomal DNA loci after DAPI/CMA3 staining on metaphases from five tamarin species, namely Leontocebus fuscicollis, Leontopithecus rosalia, Saguinus geoffroyi, Saguinus mystax and Saguinus oedipus, with the aim to investigate the distribution of repetitive sequences and their possible role in genome evolution. Our analyses revealed that all five examined species show similar karyotypes, 2n = 46, which differ mainly in the morphology of chromosome pairs 16–17 and 19–22, due to the diverse distribution of rDNA loci, the amplification of telomeric-like sequences, the presence of heterochromatic blocks and/or putative chromosomal rearrangements, such as inversions. The differences in cytogenetic traits between species of tamarins are discussed in a comparative phylogenetic framework, and in addition to data from previous studies, we underline synapomorphies and apomorphisms that appeared during the diversification of this group of New World monkeys.

Centromeric enrichment of LINE-1 retrotransposon in two species of South American monkeys Alouatta belzebul and Ateles nancymaae (Platyrrhini, Primates)

“…Furthermore, although transposable elements and satellite DNA present differences in their structure, genomic organization, spreading mechanisms and evolutionary dynamics, several studies have highlighting their relatedness, with transitions from transposable elements to alpha-satellite DNA, and vice versa, through a process known as the DNA remodeling mechanism (Mestrovich et al 2015;Paco et al 2019). The possible link between transposable elements and alphasatellite DNA, could be show in the LINE signal amplification at the centromere position of subtelocentric/ acrocentric chromosome p arms, localizing with heterochromatin C-positive bands in Ateles chromosomes; these regions are the same where often it is found telomeric signal probes and rDNA probes amplification in many primates, as previous works have demonstrated (Mazzoleni et al 2017, Ceraulo et al, 2021a; thus, this observation presumably indicates that these LINE-1, alpha-satellite and other repetitive sequences could be involved to this DNA remodeling mechanism. However, considering that LINE have also been linked with chromosomal rearrangements (Böhne et al 2008;de Sotero-Caio et al 2017, Klein andO'Neill 2018), we should take into consideration that these sequences could have had a role in the process leading to the increased rates of chromosomal evolution responsible for the highly rearranged karyotypes of many taxa; for example, the link between evolutionary reshufflings and LI accumulation have been hypothesized in other platyhirrine species Saguinus mystax, Leontocebus fuscicollis, Leontopithecus rosalia (Ceraulo et al, 2021b) and from data obtained in rodent genera, where the most derived species display a higher level of LINE-1 accumulation on both autosomal and sex chromosomes then the more conserved ones (with accumulation usually only in the sex chromosomes) (Dobigny et al 2004;Rebuzzini et al 2009;Vieira-Dasilva et al 2016).…”

“…BAC-FISH has also been performed on Aotus and Alouatta showing intrachromosomal rearrangements (Dumas et al 2015;Scardino et al 2020a). Although, these species have been studied through molecular cytogenetics with different kinds of probes, repetitive sequences have been poorly studied and, among them, only rDNA and Telomeric probes have been mapped often (Mazzoleni et al 2017;, Ceraulo et al 2021a). The study of these sequence probes' distribution can help locate useful cytogenetic markers for evolutionary and phylogenetic studies.…”

Mapping Retrotransposon LINE-1 Sequences into Two Cebidae Species and Homo sapiens Genomes and a Short Review on Primates

“…To extend LINE-1 distribution analysis to more primate samples, we used FISH to map LINE-1 probes in two platyrrhine species and in humans. The platyrrhine species are taxa characterised by a high level of rearrangements [ 29 , 30 , 31 , 32 ]; for this reason, they could be a useful model for the study of LINE-1 and chromosome evolution. The LINE-1 mapping results on H. sapiens (Hominidae, Catarrhini), S. apella , and C. capucinus (Cebidae, Platyrrhini) (Linnaeus, 1758) permit us to discuss LINE-1 evolution in a comparative perspective in light of previously published cytogenomic data.…”

Chromosome Painting in Cercopithecus petaurista (Schreber, 1774) Compared to Other Monkeys of the Cercopithecini Tribe (Catarrhini, Primates)

“…This analysis was performed in order to clarify the phylogenetic and systematic inferences regarding the tribe. Moreover, telomeric sequence probes were mapped by FISH in C. petaurista because recent works have suggested that interstitial telomeric sequences (ITSs) may be linked to the high rate of chromosome evolution in primates [ 37 , 38 , 39 , 40 , 41 ].…”