TITLE:
Changes in Gene Expression in Needles and Stems of Pinus radiata Rootstock Plants of Different Ontogenic Age
AUTHORS:
Carolina Alvarez, Luis Valledor, Patricia Sáez, Rodrigo Hasbún, Manuel Sánchez-Olate, María Jesús Cañal, Darcy Ríos
KEYWORDS:
Plant Ageing, Gene Expression, Morphogenetic Competence, Pinus radiate
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.7 No.8,
June
13,
2016
ABSTRACT: A major problem in forest
clonal productivity is the loss of morphogenetic capability with the increasing
age of plants. However, despite of the importance of loss of morphogenetic competence,
very little research has been done about the underlying mechanisms involved in this
process. For this reason, a gene expression analysis using dot blot technique was
performed in needles and stems of 1- and 3-year old Pinus radiata rootstock plants
with a proved decrease in morphogenetic competence. Needles of one year old rootstock
plants showed a higher number of up-regulated in genes mainly corresponding to photosynthesis
and protein synthesis, degradation and modification, reflecting a higher number
of active pathways in younger hedges, contrary to the older ones. Gene expression
profiles found in stems are in agreement with those found in needles, indicating
more active pathways in younger rootstock plants than in older ones. Several transcripts
regulating transcription and translation were up-regulated in young competent tissues.
Three-year-old stems presented an increase in the expression of an ethylene response
factor, involved in plant organ senescence, indicating that pathways involved in
senescence and ageing might inhibit the adventitious root formation, as in the older
cuttings.