A01：Plant iron sensing and regulation by iron-zinc switching of ubiquitin ligases
Takanori KOBAYASHI
（Research Institute for Bioresources and Biotechnology, Ishikawa Prefectural University）
Lab website
To acquire adequate amounts of iron, living organisms sense iron abundance and induce sets of genes for iron uptake and transport under iron deficiency. This project aims to clarify the mechanism of iron sensing and regulation by HRZ ubiquitin ligases, putative iron sensors in plant cells negatively regulating iron deficiency responses in plants. Plants might sense iron status by alteration of HRZ function by binding of each domain to either iron, zinc or none of them (iron-zinc switching). In this project, we aim to clarify alteration of HRZs’ stability, ubiquitination activity, interaction to other proteins, and iron deficiency responses by iron and zinc environments at molecular and plant levels, as well as clarify HRZs’ structure and its alteration by metal binding. This project will lead to identification of plant iron sensing molecules and iron signals, as well as generation of crops with improved productivity in problem soils and increased mineral contents including iron.
Major publications
Kobayashi, T., Ozu, A., Kobayashi, S., An, G., Jeon, J.S. and Nishizawa, N.K.
“OsbHLH058 and OsbHLH059 transcription factors positively regulate iron deficiency responses in rice.”
Plant Mol. Biol. 101, 471-486 (2019)
doi: 10.1007/s11103-019-00917-8
Aung, M.S., Kobayashi, T., Masuda, H. and Nishizawa, N.K.
“Rice HRZ ubiquitin ligases are crucial for the response to excess iron.”
Physiol. Plant. 163, 282-296 (2018)
doi: 10.1111/ppl.12698
Kobayashi, T. and Nishizawa, N.K.
“Iron sensors and signals in response to iron deficiency.”
Plant Sci. 224, 36-43 (2014)
doi: 10.1016/j.plantsci.2014.04.002
Kobayashi, T., Nagasaka, S., Senoura, T., Itai, R.N., Nakanishi, H. and Nishizawa, N.K.
“Iron-binding haemerythrin RING ubiquitin ligases regulate plant iron responses and accumulation.”
Nat. Commun. 4, 2792 (2013)
doi: 10.1038/ncomms3792
Kobayashi, T. and Nishizawa, N.K.
“Iron uptake, translocation, and regulation in higher plants.”
Annu. Rev. Plant Biol. 63, 131-152 (2012)
doi: 10.1146/annurev-arplant-042811-105522