Transcriptomic and physiological characterization of the fefe mutant of melon (Cucumis melo) reveals new aspects of iron–copper crosstalk. Issue 4 (27th June 2014)

• Record Type: Journal Article
• Authors: Waters, Brian M.; McInturf, Samuel A.; Amundsen, Keenan
• Is Part Of: New phytologist. Volume 203:Issue 4(2014)
• Page Start: 1128
• Page End: 1145
• Publication Date: 2014-06-27
• Subjects: Botany -- Periodicals; 580
• DOI: 10.1111/nph.12911
• Languages: English
• ISSNs: 0028-646X

Abstract

<abstract abstract-type="main" id="nph12911-abs-0001"> <title>Summary</title> <p> <list id="nph12911-list-0001" list-type="bullet"> <list-item> <p>Iron (Fe) and copper (Cu) homeostasis are tightly linked across biology. In previous work, Fe deficiency interacted with Cu‐regulated genes and stimulated Cu accumulation.</p> </list-item> <list-item> <p>The C940‐fe (<italic>fefe</italic>) Fe‐uptake mutant of melon (<italic>Cucumis melo</italic>) was characterized, and the <italic>fefe</italic> mutant was used to test whether Cu deficiency could stimulate Fe uptake. Wild‐type and <italic>fefe</italic> mutant transcriptomes were determined by RNA‐seq under Fe and Cu deficiency.</p> </list-item> <list-item> <p> <italic>FeFe</italic>‐regulated genes included core Fe uptake, metal homeostasis, and transcription factor genes. Numerous genes were regulated by both Fe and Cu. The <italic>fefe</italic> mutant was rescued by high Fe or by Cu deficiency, which stimulated ferric‐chelate reductase activity, <italic>FRO2</italic> expression, and Fe accumulation. Accumulation of Fe in Cu‐deficient plants was independent of the normal Fe‐uptake system. One of the four <italic>FRO</italic> genes in the melon and cucumber (<italic>Cucumis sativus</italic>) genomes was Fe‐regulated, and one was Cu‐regulated. Simultaneous Fe and Cu deficiency synergistically up‐regulated Fe‐uptake gene expression.</p> </list-item> <list-item> <p>Overlap in Fe and Cu deficiency transcriptomes highlights the importance of Fe–Cu crosstalk in metal homeostasis. The <italic>fefe</italic> gene is not orthologous to <italic>FIT</italic>, and thus identification of this gene will provide clues to help understand regulation of Fe uptake in plants.</p> </list-item> </list> </p> </abstract>