Open AccessOverexpression of Mdb HLH 104 gene enhances the tolerance to iron deficiency in apple
Author(s) -
Zhao Qiang,
Ren YiRan,
Wang QingJie,
Yao YuXin,
You ChunXiang,
Hao YuJin
Publication year - 2016
Publication title -
plant biotechnology journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.525
H-Index - 115
eISSN - 1467-7652
pISSN - 1467-7644
DOI - 10.1111/pbi.12526
Subject(s) - gene , biology , transgene , gene expression , transcription factor , microbiology and biotechnology , biochemistry
Summary Fe deficiency is a widespread nutritional disorder in plants. The basic helix‐loop‐helix ( bHLH ) transcription factors ( TF s), especially Ib subgroup bHLH TF s which are involved in iron uptake, have been identified. In this study, an IV c subgroup bHLH TF Mdb HLH 104 was identified and characterized as a key component in the response to Fe deficiency in apple. The overexpression of the Mdb HLH 104 gene noticeably increased the H + ‐ ATP ase activity under iron limitation conditions and the tolerance to Fe deficiency in transgenic apple plants and calli. Further investigation showed that Mdb HLH 104 proteins bonded directly to the promoter of the Md AHA 8 gene, thereby positively regulating its expression, the plasma membrane ( PM ) H + ‐ ATP ase activity and Fe uptake. Similarly, Mdb HLH 104 directly modulated the expression of three Fe‐responsive bHLH genes, Mdb HLH 38 , Mdb HLH 39 and Md PYE . In addition, Mdb HLH 104 interacted with 5 other IV c subgroup bHLH proteins to coregulate the expression of the Md AHA 8 gene, the activity of PM H + ‐ ATP ase and the content of Fe in apple calli. Therefore, Mdb HLH 104 acts together with other apple bHLH TF s to regulate Fe uptake by modulating the expression of the Md AHA 8 gene and the activity of PM H + ‐ ATP ase in apple.