Sulphur availability modulates Arabidopsis thaliana responses to iron deficiency

PLoS One. 2020 Aug 20;15(8):e0237998. doi: 10.1371/journal.pone.0237998. eCollection 2020.

Abstract

Among the mineral nutrients that are required for plant metabolism, iron (Fe) and sulphur (S) play a central role as both elements are needed for the activity of several proteins involved in essential cellular processes. A combination of physiological, biochemical and molecular approaches was employed to investigate how S availability influences plant response to Fe deficiency, using the model plant Arabidopsis thaliana. We first observed that chlorosis symptom induced by Fe deficiency was less pronounced when S availability was scarce. We thus found that S deficiency inhibited the Fe deficiency induced expression of several genes associated with the maintenance of Fe homeostasis. This includes structural genes involved in Fe uptake (i.e. IRT1, FRO2, PDR9, NRAMP1) and transport (i.e. FRD3, NAS4) as well as a subset of their upstream regulators, namely BTS, PYE and the four clade Ib bHLH. Last, we found that the over accumulation of manganese (Mn) in response to Fe shortage was reduced under combined Fe and S deficiencies. These data suggest that S deficiency inhibits the Fe deficiency dependent induction of the Fe uptake machinery. This in turn limits the transport into the root and the plant body of potentially toxic divalent cations such as Mn and Zn, thus limiting the deleterious effect of Fe deprivation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / genetics
  • Arabidopsis / metabolism*
  • Gene Expression Regulation, Plant
  • Homeostasis
  • Iron / metabolism
  • Iron Deficiencies*
  • Sulfur / metabolism*
  • Transcription, Genetic

Substances

  • Sulfur
  • Iron

Grants and funding

KR was supported by fellowships from the French National Research Agency (ANR-17-CE20-0008) and the INRAE (department of “Biologie et Amélioration des Plantes”). FG was supported by a fellowship from the China Scholarship Council (CSC). NT was supported by a fellowship from the French “Ministère de l’enseignement supérieur et de la recherche”.