title: Hormone regulation of rhizome development in tall fescue (Festuca arundinacea) associated with proteomic changes controlling respiratory and amino acid metabolism.
abstract: Rhizomes are underground stems with meristematic tissues capable of generating shoots and roots. However, mechanisms controlling rhizome formation and growth are yet to be completely understood. The objectives of this study were to investigate whether rhizome development could be regulated by cytokinins (CKs) and gibberellic acids (GAs), and determine underlying mechanisms of regulation of rhizome formation and growth of tall fescue (Festuca arundinacea) by a CK or GA through proteomic and transcript analysis.
  
  
  
  A rhizomatous genotype of tall fescue ('BR') plants were treated with 6-benzylaminopurine (BAP, a synthetic cytokinin) or GA3 in hydroponic culture in growth chambers. Furthermore, comparative proteomic analysis of two-dimensional electrophoresis and mass spectrometry were performed to investigate proteins and associated metabolic pathways imparting increased rhizome number by BAP and rhizome elongation by GA3 KEY RESULTS: BAP stimulated rhizome formation while GA3 promoted rhizome elongation. Proteomic analysis identified 76 differentially expressed proteins (DEPs) due to BAP treatment and 37 DEPs due to GA3 treatment. Cytokinin-related genes and cell division-related genes were upregulated in the rhizome node by BAP and gibberellin-related and cell growth-related genes in the rhizome by GA3 CONCLUSIONS: Most of the BAP- or GA-responsive DEPs were involved in respiratory metabolism and amino acid metabolism. Transcription analysis demonstrated that genes involved in hormone metabolism, signalling pathways, cell division and cell-wall loosening were upregulated by BAP or GA3 The CK and GA promoted rhizome formation and growth, respectively, by activating metabolic pathways that supply energy and amino acids to support cell division and expansion during rhizome initiation and elongation in tall fescue.
authors.affiliation: College of Agro-grassland Science Nanjing Agricultural University, Nanjing 210095, PR China Department of Plant Biology and Pathology, Rutgers, the State University of New Jersey, New Brunswick, NJ 08901, USA.
authors.forename: Xiqing
authors.initials: X
authors.lastname: Ma
authors.affiliation: National Engineering Laboratory for Tree Breeding, Beijing Forestry University, Beijing 100083, PR China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Xu
authors.affiliation: Department of Plant Biology and Pathology, Rutgers, the State University of New Jersey, New Brunswick, NJ 08901, USA.
authors.forename: William A
authors.initials: WA
authors.lastname: Meyer
authors.affiliation: Department of Plant Biology and Pathology, Rutgers, the State University of New Jersey, New Brunswick, NJ 08901, USA huang@aesop.rutgers.edu.
authors.forename: Bingru
authors.initials: B
authors.lastname: Huang
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D001593:Benzyl Compounds / Q000494:pharmacology*; D003583:Cytokinins / Q000378:metabolism; D031751:Festuca / Q000187:drug effects* / Q000254:growth & development / Q000502:physiology; D005838:Genotype; D005875:Gibberellins / Q000378:metabolism; D010937:Plant Growth Regulators / Q000378:metabolism / Q000494:pharmacology*; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development / Q000502:physiology; D040901:Proteomics; D011687:Purines / Q000494:pharmacology*; D027343:Rhizome / Q000187:drug effects / Q000254:growth & development / Q000502:physiology
chemical_list: D000596:Amino Acids; D001593:Benzyl Compounds; D003583:Cytokinins; D005875:Gibberellins; D010937:Plant Growth Regulators; D011687:Purines; C007842:gibberellic acid; C480551:benzylaminopurine
keywords: Rhizome; hormone; protein; tall fescue; transcription