Agriculture Reference
In-Depth Information
During cold acclimation, homologs of LEA (late
embryogenesis abundant) proteins also accumulate in many
plant species (Thomoshow 1999). During extracellular
freezing, liquid water is withdrawn out of the cells, resulting
in cellular dehydration (Guy 1990). Therefore, it has been
suggested that LEA protein homologs may play a role in
conferring tolerance in plant cells under freezing condition
(Thomoshow 1999).
Cold acclimatization-induced accumulation of cold
regulated (COR) proteins, the majority of these proteins have
structural similarity with LEA proteins. LEA proteins have a
highly hydrophilic feature and remain soluble upon boiling.
LEA proteins have simple and a few amino acids especially
hydrophilic proteins and share the unique property of heat
stability.
Recently, to know the molecular basis, much emphasis has
been given to gene expression. However, in order to apply such
methods more knowledge and acclimatization is required.
One step in this direction is to analyze gene expression data
generated from cold stressed rice. EST sequencing and cDNA
microarray technologies suggests that rice is cold responsive,
to many of the previously identifi ed cold regulated genes
having their counterpart in the species. In rice, however,
the response is less dynamic than in the model organization
Arabidopsis thaliana and this may explain its inability to fully
cold acclimatization (Lindlof 2008).
Plants respond with changes in their pattern of gene
expression and protein products when exposed to low
temperatures. Thus, ability to adapt has an impact on the
distribution of survival of the plant, and on crop yields.
Many species of tropical and subtropical origin are injured or
killed by a nonfreezing low temperatures, and exhibit various
