Abstract
BackgroundDespite its relevance, almost no studies account for the genetic control in the early stages of tree development, i.e. from germination on. This study seeks to make a quite complete transcriptome for olive development and to elucidate the dynamic regulation of the transcriptomic response during the early-juvenile period by RNAseq time-series expression analysis. The transcriptome was made from 342,049,597 paired-end reads of 101 bp in length. The assembled transcriptome contained 109,125 unigenes (N50 = 1490 bp, average length = 839).ResultsThe time-series-expression analysis showed that, embryonic structures present at the first month after the induction of germination reached a more differentiated state in two-month-old seedlings. Once the plants were between three and four months old and reached a size around 6–7 nodes, the first developmental stages appeared to be complete and the developing seedling became a juvenile plant. In addition, an AGL-gene was rapidly downregulated during the induction of germination. The repression of this gene was very strong, as evidenced by the low levels of gene expression during plant development from the embryonic seedling to undetectable levels of expression in the adult tree. These results suggest that this gene may be involved in seed dormancy and could be a repressor of the germination. Also, an APL1-like olive gene was found to be expressed at high levels during flowering, and was also expressed during the cold incubation in the activation of embryo germination, suggesting a probable role in embryonic development.ConclusionsThe early development from germination to the juvenile stage of olive seedlings occurred when plants reached a size around 6–7 nodes, and general changes of relevant groups of genes involved in development are described. An AGL-gene was proposed to be involved in germination repression. An APL1-like gene was found to have a probable role in embryonic development.
Highlights
Despite its relevance, almost no studies account for the genetic control in the early stages of tree development, i.e. from germination on
MRNA profile during the seedling growth of identified genes coding for transcription factors involved in plant development Samples were taken from the whole seed or activated germinating embryo in the first two weeks of plant growth
Ten genes previously shown to code for olive transcription factors [2] and a gene previously identified as likely being involve in olive plant development [3] were analyzed for gene expression during early development (Fig. 2)
Summary
Almost no studies account for the genetic control in the early stages of tree development, i.e. from germination on. This study seeks to make a quite complete transcriptome for olive development and to elucidate the dynamic regulation of the transcriptomic response during the early-juvenile period by RNAseq time-series expression analysis. The study revealed that transcriptomic changes preceded the juvenile-to-adult phase transition and occurred when the tree trunk had developed between 30 and 45 nodes and at least 18 months prior to the first flowering. In Arabidopsis, the main genetic changes at the juvenile-to-adult phase transition are controlled by a complementary expression pattern of the miRNAs, miR156 and miR172 [4, 5]. This study was aimed at developing a quite complete transcriptome dataset for olive development using RNAseq by Illumina and at studying the dynamic regulation of the transcriptomic response during the early-juvenile period by time-series-expression analysis
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
