Metabolome and transcriptome profiling reveal new insights into somatic embryo germination in Norway spruce (Picea abies)

TY - JOUR

T1 - Metabolome and transcriptome profiling reveal new insights into somatic embryo germination in Norway spruce (Picea abies)

AU - Dobrowolska, Izabela

AU - Businge, Edward

AU - Abreu, Ilka N.

AU - Moritz, Thomas

AU - Egertsdotter, Ulrika

PY - 2017/12

Y1 - 2017/12

N2 - Transcriptome, metabolome and histological profiling were performed on normal and aberrant somatic embryo germinants of Norway spruce (Picea abies L. Karst) providing a simplistic systems biology description of conifer germination. Aberrant germinants (AGs) formed periderm-like tissue at the apical pole and lacked shoot growth above the cotyledons. Transcriptome profiling (RNA-Sequencing) revealed a total of 370 differentially expressed genes at ≥1 or ≤-1 log2-fold change, where 92% were downregulated in AGs compared with normal germinants (NGs). Genes associated with shoot apical meristem formation were downregulated in AGs, or not differentially expressed between AGs and NGs. Genes involved in hormone signaling and transport were also down-regulated. Metabolite profiling by gas chromatographymass spectrometry (MS) and liquid chromatography MS revealed biochemical difference between AGs and NGs, notably increased levels of sugars including glucose in AGs. Genes involved in glucose signaling were down-regulated and genes involved in starch biosynthesis were up-regulated, suggesting involvement of sugar signaling during late embryo development and germination. The overall results provide new data enabling further studies to confirm potential markers for a normal germination process in conifers.

AB - Transcriptome, metabolome and histological profiling were performed on normal and aberrant somatic embryo germinants of Norway spruce (Picea abies L. Karst) providing a simplistic systems biology description of conifer germination. Aberrant germinants (AGs) formed periderm-like tissue at the apical pole and lacked shoot growth above the cotyledons. Transcriptome profiling (RNA-Sequencing) revealed a total of 370 differentially expressed genes at ≥1 or ≤-1 log2-fold change, where 92% were downregulated in AGs compared with normal germinants (NGs). Genes associated with shoot apical meristem formation were downregulated in AGs, or not differentially expressed between AGs and NGs. Genes involved in hormone signaling and transport were also down-regulated. Metabolite profiling by gas chromatographymass spectrometry (MS) and liquid chromatography MS revealed biochemical difference between AGs and NGs, notably increased levels of sugars including glucose in AGs. Genes involved in glucose signaling were down-regulated and genes involved in starch biosynthesis were up-regulated, suggesting involvement of sugar signaling during late embryo development and germination. The overall results provide new data enabling further studies to confirm potential markers for a normal germination process in conifers.

U2 - 10.1093/treephys/tpx078

DO - 10.1093/treephys/tpx078

M3 - Journal article

SN - 1568-2544

VL - 37

SP - 1752

EP - 1766

JO - Tree Physiology

JF - Tree Physiology

IS - 12

ER -