- Title
- Connecting stress to development in the induction of somatic embryogenesis
- Creator
- Rose, Ray J.; Sheahan, Michael B.; Tiew, Terence W.-Y.
- Relation
- Somatic Embryogenesis and Gene Expression p. 146-165
- Publisher
- Narosa Publishing House
- Resource Type
- book chapter
- Date
- 2013
- Description
- Tissue explants, in response to excision and culture in an enriched culture medium, experience both wound and osmotic stresses. In the absence of appropriate hormones, these stresses ultimately lead to death of the tissue. However, provided appropriate hormone(s) exist in the medium, usually an auxin or an auxin plus a cytokinin, somatic embryogenesis can be induced. Wounding and osmotic stress stimulate the production of reactive oxygen species (ROS) — molecules that are produced in response to both abiotic and biotic stresses during normal plant growth and development. ROS and auxin (often in conjunction with cytokinin) promote cellular dedifferentiation and the induction of cell division. A portion of these newly divided cells ultimately become totipotent stem cells, of which some will redifferentiate and commit to a developmental pathway resulting in embryogenesis. In the Medicago truncatula somatic embryogenesis system, ethylene is synthesised by explants in response to wound-induced ROS and auxin and cytokinin in the medium. Ethylene in turn induces expression of MtSERF1, a transcription factor that appears to connect stress and developmental signalling pathways and is essential for the subsequent signal transduction cascade that leads to the formation of somatic embryos. In this chapter, we discuss the interaction of stress and hormonal signalling in the induction of somatic embryogenesis.
- Subject
- osmotic stresses; wounds; plant growth
- Identifier
- http://hdl.handle.net/1959.13/1328147
- Identifier
- uon:25836
- Identifier
- ISBN:9788184872286
- Language
- eng
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