Abstract Detail

Phylogenomics

Pascual-Díaz, Joan Pere [1], Vitales, Daniel [1], Kovarik, Ales [2], Garnatje, Teresa [1], Rodriguez, Roi [1], Garcia, Sonia [1].

Repeat contribution to genome size ups and downs in the sunflower family.

Angiosperms show a large range of genome size (GS) variation, which may have significant evolutionary causes and consequences, including polyploidy and diversification. A large fraction of plant genomes is constituted by repetitive elements, including tandemly repeated DNA, such as satellite DNA, and dispersed DNA such as transposable elements, the latter accounting for the highest percentage of genome composition. Using a wide representation of species from the sunflower family (Asteraceae), one of the most diversified and abundant of angiosperms, we aim to understand how GS varies in relation to the repeat content. We have analysed and compared the repetitive content of 17 tribes and 37 species from Asteraceae and sister family Calyceraceae through RepeatExplorer. Genome size has been assessed by flow cytometry. Typically, Ty1-Copia (particularly SIRE lineages) and Ty3-Gypsy (particularly Tekay and Athila lineages) LTR-retotransposons are the most abundant in most species (around 20%), while other transposable elements are specific of certain tribal, generic, or specific levels. The analysis of the repeatome may help us to understand the GS shifts appearing in this megadiverse family. We detected the possible genomic contributors of an increased GS in tribe Anthemideae, showing larger genomes than most tribes in Asteraceae. In other tribes such as Gnaphalieae, where the average GS is lower than in the remaining tribes, we detected which repetitive DNA elements are missing or particularly reduced.

1 - Spanish Research Council (CSIC), Institut Botanic De Barcelona, Passeig del Migdia s/n, Barcelona, 08038, Spain
2 - Academy of Sciences of the Czech Republic, Institute of Biophysics, Kralovopolska 135, Brno, CZ-61265, Czech Republic

Keywords:
Asteraceae
Repeatome
phylogenomics
transposable elements
chloroplast DNA
genome size.

Presentation Type: Poster
Session: P3, Phylogenomics Posters
Location: Virtual/Virtual
Date: Wednesday, July 21st, 2021
Time: 5:00 PM(EDT)
Number: P3PL018
Abstract ID:637
Candidate for Awards:None