Anatomic Studies of Gamma‐irradiated Wheat Growing Without Cell Division

Foard, Donald E.; Haber, Alan H.

doi:10.1002/j.1537-2197.1961.tb11665.x

Cited by 37 publications

(21 citation statements)

References 26 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Our results obtained by reducing the activity of an essential kinase of the plant cell cycle support the observations made in a study of y-irradiated wheat seedlings growing without DNA synthesis and cell division (Foard and Haber, 1961;Haber, 1962). These studies showed that the initial development of irradiated seedlings parallels that of non-irradiated wheat.…”

Section: Does Reversible Tyrosine Phosphorylation Play a Role In Plansupporting

confidence: 89%

Dominant negative mutants of the Cdc2 kinase uncouple cell division from iterative plant development.

et al. 1995

View full text Add to dashboard Cite

Because plant cells do not move and are surrounded by a rigid cell wall, cell division rates and patterns are believed to be directly responsible for generating new structures throughout development. To study the relationship between cell division and morphogenesis, transgenic tobacco and Arabidopsis plants were constructed expressing dominant mutations in a key regulator of the Arabidopsis cell cycle, the Cdc2a kinase. Plants constitutively overproducing the wild‐type Cdc2a or the mutant form predicted to accelerate the cell cycle did not exhibit a significantly altered development. In contrast, a mutation expected to arrest the cell cycle abolished cell division when expressed in Arabidopsis, whereas some tobacco plants constitutively producing this mutant protein were recovered. These plants had a reduced histone H1 kinase activity and contained considerably fewer cells. These cells were, however, much larger and underwent normal differentiation. Morphogenesis, histogenesis and developmental timing were unaffected. The results indicate that, in plants, the developmental controls defining shape can act independently from cell division rates.

show abstract

Section: Does Reversible Tyrosine Phosphorylation Play a Role In Plansupporting

confidence: 89%

Dominant negative mutants of the Cdc2 kinase uncouple cell division from iterative plant development.

et al. 1995

View full text Add to dashboard Cite

show abstract

“…Although the possibility cannot be totally excluded that a residual amount of CDKA;1.N146 protein may remain in the cells after they have left the meristem (because of protein stability), and thus contribute to the reduced leaf cell number, the data presented indicate that a reduced cell division rate within the meristem exerts a severe negative effect on cell divisions outside the meristem. As noted previously, early stages of leaf primordium development can take place without any cell division (Foard and Haber, 1961; The values are means of three independent replicates. The ACTIN2, EF1-a and CYTOCHROME B5 expression levels were used as a reference.…”

Section: Discussionmentioning

confidence: 84%

Cyclin-dependent kinase activity retains the shoot apical meristem cells in an undifferentiated state

Gaamouche¹,

Manes²,

Kwiatkowska³

et al. 2010

The Plant Journal

View full text Add to dashboard Cite

SUMMARYAs the shoot apex produces most of the cells that comprise the aerial part of the plant, perfect orchestration between cell division rates and fate specification is essential for normal organ formation and plant development. However, the inter-dependence of cell-cycle machinery and meristem-organizing genes is still poorly understood. To investigate this mechanism, we specifically inhibited the cell-cycle machinery in the shoot apex by expression of a dominant negative allele of the A-type cyclin-dependent kinase (CDK) CDKA;1 in meristematic cells. A decrease in the cell division rate within the SHOOT MERISTEMLESS domain of the shoot apex dramatically affected plant growth and development. Within the meristem, a subset of cells was driven into the differentiation pathway, as indicated by premature cell expansion and onset of endo-reduplication. Although the meristem structure and expression patterns of the meristem identity genes were maintained in most plants, the reduced CDK activity caused splitting of the meristem in some plants. This phenotype correlated with the level of expression of the dominant negative CDKA;1 allele. Therefore, we propose a threshold model in which the effect of the cell-cycle machinery on meristem organization is determined by the level of CDK activity.

show abstract

“…Experimental systems have been described in which vascular tissue differentiates without an immediately prior cell division, but these all seen1 to be cases in which the "inducing" cell cycle, if such exists, can be interpreted as having occurred at some earlier stage during growth of the tissue. For example, Foard and Haber (1961) demonstrated that gamma plantlets (irradiated wheat seeds which germinate and grow without any cell division) still produce normal xylem elements in the central cylinder of the root, presumably from procambium already present in the embryo. Another possible example is seen in the studies of Siebers (1971) on the development of interfascicular tissue in castor bean seedlings.…”

Section: Introductionmentioning

confidence: 98%