title: Profiling microRNAs in Eucalyptus grandis reveals no mutual relationship between alterations in miR156 and miR172 expression and adventitious root induction during development.
abstract: BACKGROUND
  The change from juvenile to mature phase in woody plants is often accompanied by a gradual loss of rooting ability, as well as by reduced microRNA (miR) 156 and increased miR172 expression.
  
  
  RESULTS
  We characterized the population of miRNAs of Eucalyptus grandis and compared the gradual reduction in miR156 and increase in miR172 expression during development to the loss of rooting ability. Forty known and eight novel miRNAs were discovered and their predicted targets are listed. The expression pattern of nine miRNAs was determined during adventitious root formation in juvenile and mature cuttings. While the expression levels of miR156 and miR172 were inverse in juvenile and mature tissues, no mutual relationship was found between high miR156 expression and rooting ability, or high miR172 expression and loss of rooting ability. This is shown both in E. grandis and in E. brachyphylla, in which explants that underwent rejuvenation in tissue culture conditions were also examined.
  
  
  CONCLUSIONS
  It is suggested that in these Eucalyptus species, there is no correlation between the switch of miR156 with miR172 expression in the stems and the loss of rooting ability.
authors: Aviv
authors: A
authors: Levy
authors: David
authors: D
authors: Szwerdszarf
authors: Mohamad
authors: M
authors: Abu-Abied
authors: Inna
authors: I
authors: Mordehaev
authors: Yossi
authors: Y
authors: Yaniv
authors: Joseph
authors: J
authors: Riov
authors: Tzahi
authors: T
authors: Arazi
authors: The Institute of Plant Sciences, Volcani Center, P,O, Box 6, Bet-Dagan 5025000, Israel. vhesadot@agri.gov.il.
authors: Einat
authors: E
authors: Sadot
mesh_terms: D005052:Eucalyptus / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D059014:High-Throughput Nucleotide Sequencing; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D018517:Plant Roots / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D018547:Plant Stems / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D034622:RNA Interference; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism*; D017423:Sequence Analysis, RNA; D059467:Transcriptome
chemical_list: D035683:MicroRNAs; D018749:RNA, Plant