Article

Regulation of phosphate starvation responses in higher plants

School of Plant Biology, University of Western Australia, Crawley, WA 6009, Australia.
Annals of Botany (Impact Factor: 3.3). 02/2010; 105(4):513-26. DOI: 10.1093/aob/mcq015
Source: PubMed

ABSTRACT Phosphorus (P) is often a limiting mineral nutrient for plant growth. Many soils worldwide are deficient in soluble inorganic phosphate (P(i)), the form of P most readily absorbed and utilized by plants. A network of elaborate developmental and biochemical adaptations has evolved in plants to enhance P(i) acquisition and avoid starvation.
Controlling the deployment of adaptations used by plants to avoid P(i) starvation requires a sophisticated sensing and regulatory system that can integrate external and internal information regarding P(i) availability. In this review, the current knowledge of the regulatory mechanisms that control P(i) starvation responses and the local and long-distance signals that may trigger P(i) starvation responses are discussed. Uncharacterized mutants that have P(i)-related phenotypes and their potential to give us additional insights into regulatory pathways and P(i) starvation-induced signalling are also highlighted and assessed.
An impressive list of factors that regulate P(i) starvation responses is now available, as is a good deal of knowledge regarding the local and long-distance signals that allow a plant to sense and respond to P(i) availability. However, we are only beginning to understand how these factors and signals are integrated with one another in a regulatory web able to control the range of responses demonstrated by plants grown in low P(i) environments. Much more knowledge is needed in this agronomically important area before real gains can be made in improving P(i) acquisition in crop plants.

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Available from: Patrick M. Finnegan, May 11, 2014
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    • "transcription factor WRKY75 and SPX1 proteins) (Yang and Finnegan, 2010) on PSR. PHO2 was confirmed to be a target gene for the microRNA miR399 having miR399 target sites in the 5-untranslated region of its transcripts (Yang and Finnegan, 2010). The MYB transcription factor PHR1 was the first molecular determinant shown to be required for Pi starvation-dependent responses. "
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    • "Plants show a range of responses to a low P supply which are generally referred to as 'Pstarvation responses' (e.g., Karthikeyan et al., 2014; Plaxton & Tran, 2011; Ticconi et al., 2001; Yang & Finnegan, 2010). These P-starvation responses minimize plant P deficiency, and include decreased growth and increased root/shoot ratio, root-hair density and carboxylate exudation (Lambers et al., 2006). "
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