fgene-12-589160 March 19, 2021 Time: 12:36 # 1 ORIGINAL RESEARCH published: 25 March 2021 doi: 10.3389/fgene.2021.589160 Gene and Transposable Element Expression Evolution Following Recent and Past Polyploidy Events in Spartina (Poaceae) Delphine Giraud1, Oscar Lima1, Mathieu Rousseau-Gueutin2, Armel Salmon1 and Malika Aïnouche1* 1 UMR CNRS 6553 Ecosystèmes, Biodiversité, Evolution (ECOBIO), Université de Rennes 1, Rennes, France, 2 IGEPP, INRAE, Institut Agro, Univ Rennes, Le Rheu, France Gene expression dynamics is a key component of polyploid evolution, varying in nature, intensity, and temporal scales, most particularly in allopolyploids, where two or more sub-genomes from differentiated parental species and different repeat contents are merged. Here, we investigated transcriptome evolution at different evolutionary time scales among tetraploid, hexaploid, and neododecaploid Spartina species (Poaceae, Chloridoideae) that successively diverged in the last 6–10 my, Edited by: at the origin of differential phenotypic and ecological traits. Of particular interest Yves Van de Peer, are the recent (19th century) hybridizations between the two hexaploids Spartina Ghent University, Belgium alterniflora (2n = 6x = 62) and S. maritima (2n = 6x = 60) that resulted in Reviewed by: Pamela Soltis, two sterile F1 hybrids: Spartina × townsendii (2n = 6x = 62) in England and University of Florida, United States Spartina × neyrautii (2n = 6x = 62) in France. Whole genome duplication of Clayton J. Visger, S. × townsendii gave rise to the invasive neo-allododecaploid species Spartina anglica California State University, Sacramento, United States (2n = 12x = 124). New transcriptome assemblies and annotations for tetraploids and *Correspondence: the enrichment of previously published reference transcriptomes for hexaploids and Malika Aïnouche the allododecaploid allowed identifying 42,423 clusters of orthologs and distinguishing
[email protected] 21 transcribed transposable element (TE) lineages across the seven investigated Specialty section: Spartina species.