Growth‐phase‐dependent gene expression profiling of poplar (Populus alba × Populus tremula var. glandulosa) suspension cells

Abstract

Complex sequences of morphological and biochemical changes occur during the developmental course of a batch plant cell culture. However, little information is available about the changes in gene expression that could explain these changes, because of the difficulties involved in isolating specific cellular events or developmental phases in the overlapping phases of cell growth. In an attempt to obtain such information we have examined the global growth phase-dependent gene expression of poplar cells in suspension cultures by cDNA microarray analysis. Our results reveal that significant changes occur in the expression of genes with functions related to protein synthesis, cell cycling, hormonal responses and cell wall biosynthesis, as cultures progress from initiation to senescence, that are highly correlated with observed developmental and physiological changes in the cells. Genes encoding protein kinases, calmodulin and proteins involved in both ascorbate metabolism and water-limited stress responses also showed strong stage-specific expression patterns. Our report provides fundamental information on molecular mechanisms that control cellular changes throughout the developmental course of poplar cell cultures.

Differential expression of a poplar SK2-type dehydrin gene in response to various stresses

“…3C). The reason why the Podhn level was so high in the late stationary phase remains unknown, but may be related to nutrient deficiency in the culture medium and osmotic stress as the cells enter the apoptotic cell death phase (16). Nevertheless, more detailed analysis is needed to explain why Podhn mRNA increases steadily from the early exponential phase until the late stationary phase of the cell culture cycle.…”

“…Cultured plant cells can have high degrees of genetic and physiological homogeneity and thus have potential in the large-scale commercial production of various secondary metabolites (16). Cell culture systems are also useful in examining responses of cells to changes in culture conditions, cell division and growth.…”

The complete chloroplast and mitochondrial genomes of Hyunsasi tree, Populus alba x Populus glandulosa (Salicaceae)

“…Because it contributed to recover bare mountains in Korea due to low level of economy more than fifty years ago, name was changed to Hyun-sa-si following his last name (Son 2009). This tree has been used for molecular biology because Populus is a model tree and it is sterile naturally blocking spreading inserted genes, so that it been studied intensively (Lee et al 2005(Lee et al , 2007Kim et al 2012Kim et al , 2013. To understand genetic background of Hyunsasi, we completed its chloroplast and mitochondrial genomes derived from its whole genome project (InfoBoss Co., Ltd.).…”

Identification of upregulated genes in laminarin-treated poplar (Populus alba × P. tremula var. glandulosa) suspension cells by suppression subtractive hybridization and cDNA microarray

“…Poplar (Populus alba ϫ P. tremula var. glandulosa) suspension cells were maintained as described previously (LEE et al, 2007). Briefly, 1 g (fresh mass) of suspension cells were transferred to 100 ml MS liquid medium, containing 1 mg l -1 2,4-dichlorophenoxyacetic acid, 0.1 mg l -1 naphthalene acetic acid, and 0.01 mg l -1 6-benzylaminopurine, and maintained on a gyratory shaker with agitation at 130 rpm in a culture room at 22 ± 1°C.…”

“…Plant cell suspension culture provides a high degree of both genetic and physiological homogeneity and is not technically challenging (LEE et al, 2007). The technique is also useful in examining responses of cells to changes in culture conditions, cell division, and growth, as most genes involved in development and environmental responses are expressed at similar levels in culture to those found in whole plants (MENGES et al, 2003).…”