Signaling Role of Inositol and its Phosphates
- Pp. 24-49 (26)A.K.M. Shamsuddin and Guang-Yu Yang
Inositol and its phosphates are integral parts of cellular signaling. InsP<sub>6</sub> is plentiful in organisms as diverse as yeast, actinobacteria, mammals and plants. In the plant kingdom, InsP<sub>6</sub> accumulates during seed development; at the time of germination it is broken down into lower inositol phosphates and micronutrients to maintain seedling. InsP<sub>6</sub> is the most abundant of intracellular inositol phosphates in eukaryotes. In mammals InsP<sub>6</sub> maintains homeostasis, stores phosphate and acts as strong antioxidant and neurotransmitter. InsP<sub>6</sub> and other inositol phosphates including the pyrophosphates, play critical roles in cellular pathways involved in signal transduction, control of cell proliferation and differentiation, RNA export, DNA repair, energy transduction, ATP regeneration etc. By enabling communication between nucleus, cytoplasm, and the outside environment, InsP<sub>6</sub> and the other inositol phosphates play a crucial role in many aspects of cell biology.