Proteome analysis of early somatic embryogenesis inPicea glauca

Abstract

Forestry is a valuable natural resource for many countries. Rapid production of large quantities of genetically improved and uniform seedlings for restocking harvested lands is a key component of sustainable forest management programs. Clonal propagation through somatic embryogenesis has the potential to meet this need in conifers and can offer the added benefit of ensuring consistent seedling quality. Although in commercial use, mass production of conifers through somatic embryogenesis is relatively new and there are numerous biological unknowns regarding this complex developmental pathway. To aid in unravelling the embryo developmental process, two-dimensional electrophoresis was employed to quantitatively assess the expression levels of proteins across four stages of somatic embryo maturation in white spruce (0, 7, 21 and 35 days post abscisic acid treatment). Forty-eight differentially expressed proteins have been identified, which display a significant change in abundance as early as day 7 of embryo development. These proteins are involved in a variety of cellular processes, many of which have not previously been associated with embryo development. The identification of these proteins was greatly assisted by the availability of a substantial expressed sequence tag (EST) resource developed for white, sitka and interior spruce. The combined use of these spruce ESTs in conjunction with GenBank accessions for other plants improved the rate of protein identification from 38% to 62% when compared with GenBank alone using automated, high-throughput techniques. This underscores the utility of EST resources in a proteomic study of any species for which a genome sequence is unavailable.

Somatic embryogenesis of selected spruce species (Picea abies, P. omorika, P. pungens 'Glauca' and P. breweriana)

“…Such an approach to the problem of somatic embryogenesis in coniferous trees was understandable, and the positive results achieved at each stage of culture are now the basis for more advanced studies of this process, already at the molecular level (Stasolla et al 2002;BishopHurley et al 2003;Silveira et al 2004;Lippert et al 2005;Peña and Séguin 2001;Klimaszewska et al 2003).…”

Different environmental conditions at initiation of radiata pine somatic embryogenesis determine the protein profile of somatic embryos

“…close relatives, according to SwissProt database (Table 1). The fact that for one spot (enolase) more than one protein was identified may be caused by the degradation products of some proteins (Teyssier et al 2011) or by the presence of multiple isoforms of a protein (Lippert et al 2005). The presence of protein isoform with different expressionpatterns during seed maturation has already been reported in barley (Finnie et al 2006).…”

“…One approach to generate such markers and to better understand the regulation of in vitro embryogenesis is to use global transcript expression or protein profiling (Lippert et al 2005;Zhao et al 2015). Indeed, proteome profiling has been successfully applied to the systematic analysis of protein expression in several broad-leaf (Correia et al 2016) and conifer species (Teyssier et al 2011) during the different stages of the development of the somatic embryos.…”

“…In conifers, some efforts have recently been made to describe SE development at the molecular level (Jo et al 2014) and differences in proteins abundance between cell lines with contrasting embryogenic potential have been found (dos Santos et al 2016). Proteomic studies combining two-dimensional (2D) gel electrophoresis with a high degree of accuracy in protein identification by mass spectrometry (MS), are available for Cupressus sempervirens (Sallandrouze et al 1999), Picea glauca (Lippert et al 2005), Larix×eurolepis (Teyssier et al 2014) and other conifers as it was reviewed by Abril et al (2011).…”

Identification of proteins related to microspore embryogenesis responsiveness in anther cultures of winter triticale (×Triticosecale Wittm.)

“…Similarly, enolase isoenzymes displayed differential expression in developing somatic embryos of spruce (Lippert et al 2005). Authors suggested that its accumulation was caused by oxidative stress and proposed that it could be used as a molecular marker for embryogenic maturation.…”