title: Transcriptomic analysis of phenotypic changes in birch (Betula platyphylla) autotetraploids.
abstract: Plant breeders have focused much attention on polyploid trees because of their importance to forestry. To evaluate the impact of intraspecies genome duplication on the transcriptome, a series of Betula platyphylla autotetraploids and diploids were generated from four full-sib families. The phenotypes and transcriptomes of these autotetraploid individuals were compared with those of diploid trees. Autotetraploids were generally superior in breast-height diameter, volume, leaf, fruit and stoma and were generally inferior in height compared to diploids. Transcriptome data revealed numerous changes in gene expression attributable to autotetraploidization, which resulted in the upregulation of 7052 unigenes and the downregulation of 3658 unigenes. Pathway analysis revealed that the biosynthesis and signal transduction of indoleacetate (IAA) and ethylene were altered after genome duplication, which may have contributed to phenotypic changes. These results shed light on variations in birch autotetraploidization and help identify important genes for the genetic engineering of birch trees.
authors.affiliation: State Key Laboratory of Forest Genetics and Tree Breeding, Northeast Forestry University, 26 Hexing Road, Harbin 150040, China. guifengliu@yahoo.com.cn.
authors.forename: Huai-Zhi
authors.initials: HZ
authors.lastname: Mu
authors.forename: Zi-Jia
authors.initials: ZJ
authors.lastname: Liu
authors.forename: Lin
authors.initials: L
authors.lastname: Lin
authors.forename: Hui-Yu
authors.initials: HY
authors.lastname: Li
authors.forename: Jing
authors.initials: J
authors.lastname: Jiang
authors.forename: Gui-Feng
authors.initials: GF
authors.lastname: Liu
mesh_terms: D029662:Betula / Q000378:metabolism*; D004171:Diploidy; D015536:Down-Regulation; D005030:Ethylenes / Q000096:biosynthesis; D005638:Fruit / Q000378:metabolism; D020869:Gene Expression Profiling; D007210:Indoleacetic Acids / Q000378:metabolism; D010641:Phenotype; D018515:Plant Leaves / Q000378:metabolism; D011123:Polyploidy; D017423:Sequence Analysis, RNA; D015398:Signal Transduction; D015854:Up-Regulation
chemical_list: D005030:Ethylenes; D007210:Indoleacetic Acids; C030737:indoleacetic acid; C036216:ethylene