salicylic acid (sa) plays a key role in plant disease resistance and hyper-sensitive cell death but is also implicated in hardening responses to abiotic stress. the aim of this study is to examine the effects of salicylic acid on the growth, eco-physiological and biochemical characteristics in zinnia elegans plant exposed to copper stress. effects of copper (cu) on biomass, root length and shoo...

Terminal differentiation of many vascular cells involves cell wall changes. Cells first elongate their primary wall, then lay down a lignified secondary wall, which is often followed by digestion of the primary wall. Expansins are wall proteins that regulate wall changes, but little is known about the specific functions of the many individual expansin isoforms. An in vitro cell culture of synch...

The zinnia (Zinnia elegans) mesophyll cell culture tracheary element (TE) system was used to study proteinases active during developmentally programmed cell death. Substrate-impregnated gels and single-cell assays revealed high levels of proteinase activity in differentiating TEs compared with undifferentiated cultured cells and expanding leaves. Three proteinases (145, 28, and 24 kD) were excl...

We have isolated three cDNA clones (TED2, TED3, and TED4) for genes expressed preferentially in cells that redifferentiate into tracheary elements from mesophyll cells isolated from leaves of Zinnia elegans. Sequence analyses of TED clones revealed that TED2 encodes a hydrophobic polypeptide with a significant similarity to the guinea pig lens-specific protein (zeta-crystallin) and that the ded...

Cells in an organism exist within a social context— the sum of interactions with neighboring cells help to define the nature of each individual. The Zinnia system provides a unique opportunity to study in vitro the interactions between different plant cell types and the consequences for commitment to a particular cell fate. Zinnia is a model system in which mesophyll cells, released from young ...