title: Chromosome doubling to overcome the chrysanthemum cross barrier based on insight from transcriptomic and proteomic analyses.
abstract: Cross breeding is the most commonly used method in chrysanthemum (Chrysanthemum morifolium) breeding; however, cross barriers always exist in these combinations. Many studies have shown that paternal chromosome doubling can often overcome hybridization barriers during cross breeding, although the underlying mechanism has seldom been investigated.
  
  
  
  In this study, we performed two crosses: C. morifolium (pollen receptor) × diploid C. nankingense (pollen donor) and C. morifolium × tetraploid C. nankingense. Seeds were obtained only from the latter cross. RNA-Seq and isobaric tags for relative and absolute quantitation (iTRAQ) were used to investigate differentially expressed genes and proteins during key embryo development stages in the latter cross. A previously performed cross, C. morifolium × diploid C. nankingense, was compared to our results and revealed that transcription factors (i.e., the agamous-like MADS-box protein AGL80 and the leucine-rich repeat receptor protein kinase EXS), hormone-responsive genes (auxin-binding protein 1), genes and proteins related to metabolism (ATP-citrate synthase, citrate synthase and malate dehydrogenase) and other genes reported to contribute to embryo development (i.e., LEA, elongation factor and tubulin) had higher expression levels in the C. morifolium × tetraploid C. nankingense cross. In contrast, genes related to senescence and cell death were down-regulated in the C. morifolium × tetraploid C. nankingense cross.
  
  
  
  The data resources helped elucidate the gene and protein expression profiles and identify functional genes during different development stages. When the chromosomes from the male parent are doubled, the genes contributing to normal embryo developmentare more abundant. However, genes with negative functions were suppressed, suggesting that chromosome doubling may epigenetically inhibit the expression of these genes and allow the embryo to develop normally.
authors: College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China.|Jiangsu Province Engineering Lab for Modern Facility Agriculture Technology and Equipment, Nanjing, 210095, China.
authors: Fengjiao
authors: F
authors: Zhang
authors: College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China.
authors: Lichun
authors: L
authors: Hua
authors: College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China.
authors: Jiangsong
authors: J
authors: Fei
authors: College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China.
authors: Fan
authors: F
authors: Wang
authors: College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China.
authors: Yuan
authors: Y
authors: Liao
authors: College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China.
authors: Weimin
authors: W
authors: Fang
authors: College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China.
authors: Fadi
authors: F
authors: Chen
authors: College of Horticulture, Nanjing Agricultural University, Nanjing, 210095, China. nianjunteng@163.com.|Jiangsu Province Engineering Lab for Modern Facility Agriculture Technology and Equipment, Nanjing, 210095, China. nianjunteng@163.com.
authors: Nianjun
authors: 0000-0002-6524-2612
authors: N
authors: Teng
mesh_terms: D032461:Chromosomes, Plant / Q000235:genetics*; D031202:Chrysanthemum / Q000235:genetics* / Q000254:growth & development; D020869:Gene Expression Profiling; D006824:Hybridization, Genetic; D058977:Molecular Sequence Annotation; D056771:Ovule / Q000235:genetics / Q000254:growth & development; D011003:Ploidies; D040901:Proteomics; D012639:Seeds / Q000235:genetics / Q000254:growth & development
keywords: Chromosome doubling; Chrysanthemum morifolium; Cross barrier; Interspecific hybridization; RNA-Seq; iTRAQ