Descending Dysploidy and Bidirectional Changes in Genome Size Accompanied Crepis (Asteraceae) Evolution

• Published in: Genes Vol. 12; no. 9; p. 1436
• Main Authors: Senderowicz, Magdalena, Nowak, Teresa, Rojek-Jelonek, Magdalena, Bisaga, Maciej, Papp, Laszlo, Weiss-Schneeweiss, Hanna, Kolano, Bozena
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 17-09-2021; MDPI
• Subjects: Asteraceae - genetics; Asymmetry; Chromosomes; Chromosomes, Plant; Crepis - genetics; Diversification; Evolution; Evolution, Molecular; Genome Size; Genome, Plant; Genomes; Karyotypes; Karyotyping; Morphology; Nucleotide sequence; Phylogenetics; Phylogeny; Polyploidy; Standard deviation; Poland; United States > US; Germany; chromosome number; karyotype formula; phylogenetic analysis; flow cytometry; genome size
• ISSN: 2073-4425; 2073-4425
• DOI: 10.3390/genes12091436

The evolution of the karyotype and genome size was examined in species of
sensu lato. The phylogenetic relationships, inferred from the plastid and nrITS DNA sequences, were used as a framework to infer the patterns of karyotype evolution. Five different base chromosome numbers (
= 3, 4, 5, 6, and 11) were observed. A phylogenetic analysis of the evolution of the chromosome numbers allowed the inference of
= 6 as the ancestral state and the descending dysploidy as the major direction of the chromosome base number evolution. The derived base chromosome numbers (
= 5, 4, and 3) were found to have originated independently and recurrently in the different lineages of the genus. A few independent events of increases in karyotype asymmetry were inferred to have accompanied the karyotype evolution in
. The genome sizes of 33
species differed seven-fold and the ancestral genome size was reconstructed to be 1C = 3.44 pg. Both decreases and increases in the genome size were inferred to have occurred within and between the lineages. The data suggest that, in addition to dysploidy, the amplification/elimination of various repetitive DNAs was likely involved in the genome and taxa differentiation in the genus.