Transcript profiling of Zea mays roots reveals gene responses to phosphate deficiency at the plant- and species-specific levels

Abstract

Maize (Zea mays) is the most widely cultivated crop around the world; however, it is commonly affected by phosphate (Pi) deficiency in many regions, particularly in acid and alkaline soils of developing countries. To cope with Pi deficiency, plants have evolved a large number of developmental and biochemical adaptations; however, for maize, the underlying molecular basis of these responses is still unknown. In this work, the transcriptional response of maize roots to Pi starvation at 1, 3, 6, and 10 d after the onset of Pi deprivation was assessed. The investigation revealed a total of 1179 Pi-responsive genes, of which 820 and 363 genes were found to be either up- or down-regulated, respectively, by 2-fold or more. Pi-responsive genes were found to be involved in various metabolic, signal transduction, and developmental gene networks. A large set of transcription factors, which may be potential targets for crop breeding, was identified. In addition, gene expression profiles and changes in specific metabolites were also correlated. The results show that several dicotyledonous plant responses to Pi starvation are conserved in maize, but that some genetic responses appear to be more specific and that Pi deficiency leads to a shift in the recycling of internal Pi in maize roots. Ultimately, this work provides a more comprehensive view of Pi-responses in a model for economically important cereals and also sets a framework to produce Pi-specific maize microarrays to study the changes in global gene expression between Pi-efficient and Pi-inefficient maize genotypes.

The plasma membrane proteome of Medicago truncatula roots as modified by arbuscular mycorrhizal symbiosis

“…Likewise, the content of SGs as phosphorous-free glycolipids that replace phospholipids is known to increase in the PM as a response to phosphate starvation (Andersson et al 2005). Among other features reminiscent of Pi limitation stress in plants, the PM fraction of NM roots showed enhanced abundances of sulfite exporter, glycerol-3-phosphate transporter, and phosphoenolpyruvate carboxylase (PEPC) (Calderon-Vazquez et al 2008;Lan et al 2012;Kang et al 2014). Increased levels of PEPC in Pi-limited plants has been linked to enhanced synthesis and excretion of organic acids that increase Pi concentration in the soil solution (reviewed in Plaxton and Tran 2011).…”

Maize Source Leaf Adaptation to Nitrogen Deficiency Affects Not Only Nitrogen and Carbon Metabolism But Also Control of Phosphate Homeostasis

“…In Arabidopsis, several transcription factors have been identified with nitrate starvation-related changes in expression (for review, see Kant et al, 2011a). However, the knowledge transfer concerning transcriptional regulators from only distantly related species might be problematic, and research on transcriptional regulators need to be carried out in the important crop species directly (Calderon-Vazquez et al, 2008). For instance, the maize chip used in our experiment did not contain clear orthologs of the Arabidopsis transcription factors ANR1 and Dof1, which are supposed to be involved in regulation of the nitrate response (Kant et al, 2011a).…”

Acid phosphatases and growth of barley (Hordeum vulgare L.) cultivars under diverse phosphorus nutrition

“…Phosphorus is well known as an essential nutrient important in many processes like photosynthesis, respiration, regulation of enzymes activity and gene expression or signal transduction (Raghothama 1999;Rychter and Rao 2005;Calderon-Vazquez et al 2008;Nilsson et al 2010;Yao et al 2011). Phosphate deficiency is a common stress condition experienced in many different environments.…”