caa a22 4500 463209451 CHVBK 20180405153136.0 cr unu---uuuuu 170326e20071201xx s 000 0 eng 10.1007/s00412-007-0116-6 doi (NATIONALLICENCE)springer-10.1007/s00412-007-0116-6 Sex chromosomes of basal placental mammals [Elektronische Daten] [Paul Waters, Aurora Ruiz-Herrera, Gauthier Dobigny, Montserrat Garcia Caldès, Terence Robinson] Placental (eutherian) mammals are currently classified into four superordinal clades (Afrotheria, Xenarthra, Laurasiatheria and Supraprimates) of which one, the Afrotheria (a unique lineage of African origin), is generally considered to be basal. Therefore, Afrotheria provide a pivotal evolutionary link for studying fundamental differences between the sex chromosomes of human/mouse (both representatives of Supraprimates and the index species for studies of sex chromosomes) and those of the distantly related marsupials. In this study, we use female fibroblasts to investigate classical features of X chromosome inactivation including replication timing of the X chromosomes and Barr body formation. We also examine LINE-1 accumulation on the X chromosomes of representative afrotherians and look for evidence of a pseudoautosomal region (PAR). Our results demonstrate that asynchronous replication of the X chromosomes is common to Afrotheria, as with other mammals, and Barr body formation is observed across all Placentalia, suggesting that mechanisms controlling this evolved before their radiation. Finally, we provide evidence of a PAR (which marsupials lack) and demonstrate that LINE1 is accumulated on the afrotherian and xenarthran X, although this is probably not due to transposition events in a common ancestor, but rather ongoing selection to retain recently inserted LINE1 on the X. Springer-Verlag, 2007 Waters Paul Evolutionary Genomics Group, Department of Botany and Zoology, University of Stellenbosch, Private Bag X1, 7602, Matieland, South Africa aut Ruiz-Herrera Aurora Evolutionary Genomics Group, Department of Botany and Zoology, University of Stellenbosch, Private Bag X1, 7602, Matieland, South Africa aut Dobigny Gauthier Evolutionary Genomics Group, Department of Botany and Zoology, University of Stellenbosch, Private Bag X1, 7602, Matieland, South Africa aut Garcia Caldès Montserrat Unitat de Biologia Cellular i Genètica Mèdica. Facultat de Medicina, Universitat Autònoma de Barcelona, 08193-Cerdanyola del Vallès, Barcelona, Spain aut Robinson Terence Evolutionary Genomics Group, Department of Botany and Zoology, University of Stellenbosch, Private Bag X1, 7602, Matieland, South Africa aut Chromosoma Springer-Verlag 116/6(2007-12-01), 511-518 0009-5915 116:6<511 2007 116 412 https://doi.org/10.1007/s00412-007-0116-6 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00412-007-0116-6 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Waters Paul Evolutionary Genomics Group, Department of Botany and Zoology, University of Stellenbosch, Private Bag X1, 7602, Matieland, South Africa aut NATIONALLICENCE 700 1- Ruiz-Herrera Aurora Evolutionary Genomics Group, Department of Botany and Zoology, University of Stellenbosch, Private Bag X1, 7602, Matieland, South Africa aut NATIONALLICENCE 700 1- Dobigny Gauthier Evolutionary Genomics Group, Department of Botany and Zoology, University of Stellenbosch, Private Bag X1, 7602, Matieland, South Africa aut NATIONALLICENCE 700 1- Garcia Caldès Montserrat Unitat de Biologia Cellular i Genètica Mèdica. Facultat de Medicina, Universitat Autònoma de Barcelona, 08193-Cerdanyola del Vallès, Barcelona, Spain aut NATIONALLICENCE 700 1- Robinson Terence Evolutionary Genomics Group, Department of Botany and Zoology, University of Stellenbosch, Private Bag X1, 7602, Matieland, South Africa aut NATIONALLICENCE 773 0- Chromosoma Springer-Verlag 116/6(2007-12-01), 511-518 0009-5915 116:6<511 2007 116 412 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer