Abstract
Expansins are a class of proteins identified by their ability to induce the extension
of isolated plant cell walls. Expansins are encoded by an extensive multigene family
in higher plants, several members of which have been shown to be expressed in a tissue-specific
manner. Besides playing an apparently key role in wall expansion, and hence in cell
growth, expansins have been implicated in an increasing number of processes during
plant growth and development. These include: leaf organogenesis, fruit softening,
and wall disassembly. A second class of closely related proteins (referred to as β-expansins)
has been identified. Other recent advances in expansin research include the recovery
of transgenic plants with altered level of expansins, and the production of recombinant
expansins in heterologous expression systems.
Key Words
Expansin - cell wall - plant cell enlargement - plant growth
