Iron assimilation and transcription factor controlled synthesis of riboflavin in plants

• Published in: Planta Vol. 226; no. 1; pp. 147 - 158
• Main Authors: Vorwieger, A, Gryczka, C, Czihal, A, Douchkov, D, Tiedemann, J, Mock, H.-P, Jakoby, M, Weisshaar, B, Saalbach, I, Bäumlein, H
• Format: Journal Article
• Language: English
• Published: Berlin Berlin/Heidelberg : Springer-Verlag 01.06.2007; Springer-Verlag; Springer; Springer Nature B.V
• Subjects: Arabidopsis; Arabidopsis - genetics; Arabidopsis - metabolism; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Basic helix-loop-helix; Basic Helix-Loop-Helix Transcription Factors - genetics; Basic Helix-Loop-Helix Transcription Factors - metabolism; Biological and medical sciences; Complementary DNA; Excretion; Fundamental and applied biological sciences. Psychology; Genes; Iron; Iron - metabolism; Iron assimilation; Molecular and cellular biology; Molecular genetics; Nicotiana - genetics; Nicotiana - metabolism; Plant Leaves - metabolism; Plant roots; Plant Roots - metabolism; Plants; Plants, Genetically Modified; riboflavin; Riboflavin - metabolism; Seedlings; Sunflowers; Transcription factor; Transcription factors; Transcription. Transcription factor. Splicing. Rna processing; Transgenic plants; Assimilation; Riboflavin; Iron assimilation; Basic helix-loop-helix; Transcription factor
• ISSN: 0032-0935; 1432-2048
• DOI: 10.1007/s00425-006-0476-9

Iron homeostasis is vital for many cellular processes and requires a precise regulation. Several iron efficient plants respond to iron starvation with the excretion of riboflavin and other flavins. Basic helix-loop-helix transcription factors (TF) are involved in the regulation of many developmental processes, including iron assimilation. Here we describe the isolation and characterisation of two Arabidopsis bHLH TF genes, which are strongly induced under iron starvation. Their heterologous ectopic expression causes constitutive, iron starvation independent excretion of riboflavin. The results show that both bHLH TFs represent an essential component of the regulatory pathway connecting iron deficiency perception and riboflavin excretion and might act as integrators of various stress reactions.