Eight Million Years of Satellite DNA Evolution in Grasshoppers of the Genus Schistocerca Illuminate the Ins and Outs of the Library Hypothesis Palacios-Giménez, Octavio Manuel Milani, Diogo Song, Hojun Marti, Dardo A. María Dolores López León Ruiz-Ruano, Francisco J. M. Camacho, Juan Pedro Cabral-de-Mello, Diogo C. Chromosomal evolution Genome organization Tandem repeats Repetitive DNA This study was supported by the Fundação de Amparo à Pesquisa do Estado de São Paulo-FAPESP (process number 2014/11763-8) and Coordenadoria de Aperfeiçoamento de Pessoal de Nível Superior-CAPES. The authors are grateful to anonymous reviewers for valuable comments. O.M.P.-G. and F.J.R.-R. acknowledge the scholarship obtained from the Lawski Foundation (Sweden), H.S. to the U.S. National Science Foundation (Grant No. IOS-1253493) and the United State Department of Agriculture (Hatch Grant TEX0-1-6584), D.A.M. was supported by Consejo Nacional de Investigaciones Científicas y Técnicas-CONICET from Argentina. D.C.C.-d.-M. is recipient of a research productivity fellowship from the Conselho Nacional de Desenvolvimento Científico e Tecnológico-CNPq (process number 304758/2014-0). Computing ran on resources provided by the Swedish National Infrastructure for Computing (SNIC) through Uppsala Multidisciplinary Center for Advanced Computational Science (UPPMAX). We also thank Alexander Suh (Uppsala University, Uppsala/Sweden) for helpful comments on an earlier version of this manuscript and to Cristiane Mileo (UNESP-Rio Claro/SP) for helping with some figures. Satellite DNA (satDNA) is an abundant class of tandemly repeated noncoding sequences, showing high rate of change in sequence, abundance, and physical location. However, the mechanisms promoting these changes are still controversial. The library model was put forward to explain the conservation of some satDNAs for long periods, predicting that related species share a common collection of satDNAs, which mostly experience quantitative changes. Here, we tested the library model by analyzing three satDNAs in ten species of Schistocerca grasshoppers. This group represents a valuable material because it diversified during the last 7.9 Myr across the American continent from the African desert locust (Schistocerca gregaria), and this thus illuminates the direction of evolutionary changes. By combining bioinformatic and cytogenetic, we tested whether these three satDNA families found in S. gregaria are also present in nine American species, and whether differential gains and/or losses have occurred in the lineages. We found that the three satDNAs are present in all species but display remarkable interspecies differences in their abundance and sequences while being highly consistent with genus phylogeny. The number of chromosomal loci where satDNA is present was also consistent with phylogeny for two satDNA families but not for the other. Our results suggest eminently chance events for satDNA evolution. Several evolutionary trends clearly imply either massive amplifications or contractions, thus closely fitting the library model prediction that changes are mostly quantitative. Finally, we found that satDNA amplifications or contractions may influence the evolution of monomer consensus sequences and by chance playing a major role in driftlike dynamics. 2024-03-04T10:03:14Z 2024-03-04T10:03:14Z 2020-03 journal article Octavio M Palacios-Gimenez, Diogo Milani, Hojun Song, Dardo A Marti, Maria D López-León, Francisco J Ruiz-Ruano, Juan Pedro M Camacho, Diogo C Cabral-de-Mello. Eight Million Years of Satellite DNA Evolution in Grasshoppers of the Genus Schistocerca Illuminate the Ins and Outs of the Library Hypothesis. Genome Biology and Evolution, Volume 12, Issue 3, March 2020, Pages 88–102, https://doi.org/10.1093/gbe/evaa018 https://hdl.handle.net/10481/89757 10.1093/gbe/evaa018 eng http://creativecommons.org/licenses/by-nc-nd/4.0/ open access Attribution-NonCommercial-NoDerivatives 4.0 Internacional Oxford University Press