title: Rapid genetic and epigenetic alterations under intergeneric genomic shock in newly synthesized Chrysanthemum morifolium x Leucanthemum paludosum hybrids (Asteraceae).
abstract: The Asteraceae family is at the forefront of the evolution due to frequent hybridization. Hybridization is associated with the induction of widespread genetic and epigenetic changes and has played an important role in the evolution of many plant taxa. We attempted the intergeneric cross Chrysanthemum morifolium × Leucanthemum paludosum. To obtain the success in cross, we have to turn to ovule rescue. DNA profiling of the amphihaploid and amphidiploid was investigated using amplified fragment length polymorphism, sequence-related amplified polymorphism, start codon targeted polymorphism, and methylation-sensitive amplification polymorphism (MSAP). Hybridization induced rapid changes at the genetic and the epigenetic levels. The genetic changes mainly involved loss of parental fragments and gaining of novel fragments, and some eliminated sequences possibly from the noncoding region of L. paludosum. The MSAP analysis indicated that the level of DNA methylation was lower in the amphiploid (∼45%) than in the parental lines (51.5-50.6%), whereas it increased after amphidiploid formation. Events associated with intergeneric genomic shock were a feature of C. morifolium × L. paludosum hybrid, given that the genetic relationship between the parental species is relatively distant. Our results provide genetic and epigenetic evidence for understanding genomic shock in wide crosses between species in Asteraceae and suggest a need to expand our current evolutionary framework to encompass a genetic/epigenetic dimension when seeking to understand wide crosses.
authors.affiliation: College of Horticulture, Nanjing Agricultural University, China.
authors.forename: Haibin
authors.initials: H
authors.lastname: Wang
authors.forename: Jiafu
authors.initials: J
authors.lastname: Jiang
authors.forename: Sumei
authors.initials: S
authors.lastname: Chen
authors.forename: Xiangyu
authors.initials: X
authors.lastname: Qi
authors.forename: Weimin
authors.initials: W
authors.lastname: Fang
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Guan
authors.forename: Nianjun
authors.initials: N
authors.lastname: Teng
authors.forename: Yuan
authors.initials: Y
authors.lastname: Liao
authors.forename: Fadi
authors.initials: F
authors.lastname: Chen
mesh_terms: D002678:Chimera / Q000235:genetics*; D031202:Chrysanthemum / Q000235:genetics*; D019175:DNA Methylation; D004171:Diploidy; D044127:Epigenesis, Genetic; D018745:Genome, Plant; D056914:Genomic Structural Variation; D006824:Hybridization, Genetic
keywords: Asteraceae; GISH; genome changes; intergeneric hybridization; polyploidization