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

Abstract: This work focuses on the distribution of LINE-1 (a Long Interspersed Nuclear Element) inprimates and its role during evolution and as a constituent of the architecture of primate genomes.To pinpoint the LINE-1 repeat distribution and its role among primates, LINE-1 probes weremapped onto chromosomes of Homo sapiens (Hominidae, Catarrhini), Sapajus apella, and Cebuscapucinus (Cebidae, Platyrrhini) using fluorescence in situ hybridisation (FISH). The choice ofplatyrrhine species are due to the fact they are taxa characterised by a high level of rearrangements;for this reason, they could be a useful model for the study of LINE-1 and chromosome evolution.LINE-1 accumulation was found in the two Cebidae at the centromere of almost all acrocentricchromosomes 16-22 and on some bi-armed chromosomes. LINE-1 pattern was similar in the twospecies but only for chromosomes 6, 8, 10, and 18, due to intrachromosomal rearrangements inagreement with what was previously hypothesised as through g banding. LINE-1 interstitial accumulation was found in humans on the 1, 8, 9, 13-15, and X chromosomes; on chromosomes 8, 9,and 13-15, the signal was also at the centromeric position. This is in agreement with recent andcomplete molecular sequence analysis of human chromosomes 8 and some acrocentric ones. Thus,the hypothesis regarding a link between LINE-1 and centromeres as well as a link with rearrangements are discussed. Indeed, data analysis leads us to support a link between LINE-1 andinter- and intrachromosomal rearrangements, as well as a link between LINE-1 and structuralfunctions at centromeres in primates.