title: Proteomic Analysis of Immature Fraxinus mandshurica Cotyledon Tissues during Somatic Embryogenesis: Effects of Explant Browning on Somatic Embryogenesis.
abstract: Manchurian ash (Fraxinus mandshurica Rupr.) is a valuable hardwood species in Northeast China. In cultures of F. mandshurica, somatic embryos were produced mainly on browned explants. Therefore, we studied the mechanism of explant browning and its relationship with somatic embryogenesis (SE). We used explants derived from F. mandshurica immature zygotic embryo cotyledons as materials. Proteins were extracted from browned embryogenic explants, browned non-embryogenic explants, and non-brown explants, and then separated by 2-dimensional electrophoresis. Differentially and specifically expressed proteins were analyzed by mass spectrometry to identify proteins involved in the browning of explants and SE. Some stress response and defense proteins such as chitinases, peroxidases, aspartic proteinases, and an osmotin-like protein played important roles during SE of F. mandshurica. Our results indicated that explant browning might not be caused by the accumulation and oxidation of polyphenols only, but also by some stress-related processes, which were involved in programmed cell death (PCD), and then induced SE.
authors.affiliation: State Key Laboratory of Tree Genetics and Breeding, School of Forestry, Northeast Forestry University, Hexing Road 26, Harbin 150040, China. liuchunping83@gmail.com.
authors.forename: Chun-Ping
authors.initials: CP
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Tree Genetics and Breeding, School of Forestry, Northeast Forestry University, Hexing Road 26, Harbin 150040, China. yangl-cf@nefu.edu.cn.
authors.forename: Ling
authors.initials: L
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Tree Genetics and Breeding, School of Forestry, Northeast Forestry University, Hexing Road 26, Harbin 150040, China. shenhl-cf@nefu.edu.cn.
authors.forename: Hai-Long
authors.initials: HL
authors.lastname: Shen
mesh_terms: D057055:Aspartic Acid Proteases / Q000235:genetics / Q000378:metabolism; D018548:Cotyledon / Q000166:cytology / Q000378:metabolism*; D031661:Fraxinus / Q000166:cytology / Q000378:metabolism*; D010544:Peroxidases / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D058439:Plant Somatic Embryogenesis Techniques; D020543:Proteome / Q000235:genetics / Q000378:metabolism*; D013312:Stress, Physiological
chemical_list: D010940:Plant Proteins; D020543:Proteome; D010544:Peroxidases; D057055:Aspartic Acid Proteases
keywords: PCD; manchurian ash; mass spectrometry; somatic embryos; stress response