The effect of XXXX on morphology and gene expression of white spruce (Picea glauca) somatic embryos.

@entity2197 @entity2041 @entity1735 @entity377
Inclusions of @entity2041 ( @entity2197 ) in the maturation medium increased the conversion frequency of white spruce somatic embryos without the need of a partial drying treatment (PDT). This beneficial effect was the result of major alterations in morphology and gene expression during the maturation period. Compared with control embryos, @entity2197 -treated embryos showed a differential accumulation of storage products, i.e. preferential deposition of starch, the reduced formation of protein bodies, and increased vacuolation of cells. These morphological changes correlated with extensive alterations of gene expression occurring throughout the maturation period. The transcript profiles of stage-specific embryos matured with or without @entity2197 were analysed using a DNA microarray containing 2 178 cDNAs from loblolly pine (Pinus taeda). The efficiency of heterologous hybridization between spruce and pine species on microarrays has previously been documented. The results indicate that several genes involved in a variety of signal regulatory pathways were differentially expressed in developing @entity2197 - treated embryos. The transcript levels of many genes involved in @entity1735 metabolism and protein synthesis were altered by the presence of @entity2197 and denoted differences in physiology between treatments. Extensive changes in the expression of genes participating in hormone synthesis, @entity377 metabolism, and meristem formation were also observed and related to the post-embryonic performance of the embryos.
