title: Direction and extent of organelle DNA introgression between two spruce species in the Qinghai-Tibetan Plateau.
abstract: A recent model has shown that, during range expansion of one species in a territory already occupied by a related species, introgression should take place preferentially from the resident species towards the invading species and genome components experiencing low rates of gene flow should introgress more readily than those experiencing high rates of gene flow. Here, we use molecular markers from two organelle genomes with contrasted rates of gene flow to test these predictions by examining genetic exchanges between two morphologically distinct spruce Picea species growing in the Qinghai-Tibetan Plateau. The haplotypes from both mitochondrial (mt) DNA and chloroplast (cp) DNA cluster into two distinct lineages that differentiate allopatric populations of the two species. By contrast, in sympatry, the species share the same haplotypes, suggesting interspecific genetic exchanges. As predicted by the neutral model, all sympatric populations of the expanding species had received their maternally inherited mtDNA from the resident species, whereas for paternally inherited cpDNA introgression is more limited and not strictly unidirectional. Our results underscore cryptic introgressions of organelle DNAs in plants and the importance of considering rates of gene flow and range shifts to predict direction and extent of interspecific genetic exchanges.
authors: Molecular Ecology Group, Key Laboratory of Arid and Grassland Ecology, Lanzhou University, Lanzhou, Gansu 730000, China.|INRA, UMR1202 BIOGECO, 69 route d'Arcachon, F-33610 Cestas, France.|Université de Bordeaux, UMR1202 BIOGECO, F-33610 Cestas, France.
authors: Fang K
authors: FK
authors: Du
authors: Molecular Ecology Group, Key Laboratory of Arid and Grassland Ecology, Lanzhou University, Lanzhou, Gansu 730000, China.
authors: Xiao Li
authors: XL
authors: Peng
authors: Molecular Ecology Group, Key Laboratory of Arid and Grassland Ecology, Lanzhou University, Lanzhou, Gansu 730000, China.
authors: Jian Quan
authors: JQ
authors: Liu
authors: Program in Evolutionary Functional Genomics, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, NO-75326 Uppsala, Sweden.|Laboratory of Evolutionary Genomics, CAS-MPG Partner Institute for Computational Biology, Chinese Academy of Sciences, Shanghai, China.
authors: Martin
authors: M
authors: Lascoux
authors: Departments of Plant Biology and Geology, and Program in Ecology, Evolution and Conservation, University of Illinois, 265 Morrill Hall505 S. Goodwin Avenue, Urbana, IL 61801, USA.
authors: Feng Sheng
authors: FS
authors: Hu
authors: INRA, UMR1202 BIOGECO, 69 route d'Arcachon, F-33610 Cestas, France.|Université de Bordeaux, UMR1202 BIOGECO, F-33610 Cestas, France.
authors: Rémy J
authors: RJ
authors: Petit
mesh_terms: D018533:Biomass; D018742:DNA, Chloroplast / Q000235:genetics*; D004272:DNA, Mitochondrial / Q000235:genetics*; D017753:Ecosystem; D014644:Genetic Variation; D005843:Geography; D007178:Inbreeding; D058865:Introduced Species; D008957:Models, Genetic; D028222:Picea / Q000235:genetics*; D011156:Population Density; D012639:Seeds / Q000235:genetics; D061350:Sympatry; D018609:Tibet
chemical_list: D018742:DNA, Chloroplast; D004272:DNA, Mitochondrial