Changes in physiological responses and MTP (metal tolerance protein) transcripts in soybean (Glycine max) exposed to differential iron availability

A F M Mohabubul Haque; Md Atikur Rahman; Urmi Das; Md Mostafizur Rahman; Mona M Elseehy; Ahmed M El-Shehawi; Md Sarwar Parvez; Ahmad Humayan Kabir

doi:10.1016/j.plaphy.2022.03.007

Changes in physiological responses and MTP (metal tolerance protein) transcripts in soybean (Glycine max) exposed to differential iron availability

Plant Physiol Biochem. 2022 May 15:179:1-9. doi: 10.1016/j.plaphy.2022.03.007. Epub 2022 Mar 13.

Authors

A F M Mohabubul Haque¹, Md Atikur Rahman², Urmi Das³, Md Mostafizur Rahman¹, Mona M Elseehy⁴, Ahmed M El-Shehawi⁵, Md Sarwar Parvez¹, Ahmad Humayan Kabir⁶

Affiliations

¹ Molecular Plant Physiology Laboratory, Department of Botany, University of Rajshahi, Rajshahi, 6205, Bangladesh.
² Grassland and Forage Division, National Institute of Animal Science, Rural Development Administration, Cheonan, 31000, Republic of Korea.
³ Department of Microbiological Sciences, North Dakota State University, Fargo, ND, 58105, United States.
⁴ Department of Genetics, Faculty of Agriculture, University of Alexandria, Alexandria, 21545, Egypt.
⁵ Department of Biotechnology, College of Science, Taif University, P.O. Box 11099, Taif, 21944, Saudi Arabia.
⁶ Molecular Plant Physiology Laboratory, Department of Botany, University of Rajshahi, Rajshahi, 6205, Bangladesh; Department of Genetics, University of Georgia, Athens, GA, 30606, USA. Electronic address: ahmad.kabir@ru.ac.bd.

PMID: 35303501
DOI: 10.1016/j.plaphy.2022.03.007

Abstract

Members of MTP (metal tolerance protein) family are potential metal ion transporters, but little is known about how their responses and expression are altered in response to the deficiency and excess of Fe in soybean. In this study, root and shoot length and biomass in addition to leaf chlorophyll score, PSII efficiency and photosynthetic performance index were adversely affected by Fe-deficiency and excess Fe. Fe and S concentrations in the root and shoot, as well as the increased root FCR activity, consistently decreased and increased, respectively, accompanied by elevated Zn levels under Fe deficiency and Fe toxicity. This implies that Fe-uptake of plants subjected to differential Fe availability are likely determined by S and Zn nutritional status. In qPCR analysis, GmMTP5, GmMTP7, GmMTP8, and GmMTP10 genes showed downregulation under Fe shortage, whereas GmMTP6 and GmMTP11 were significantly upregulated due to Fe-toxicity. Further, GmMTP1, GmMTP3, GmMTP6, GmMTP7, and GmMTP10 were significantly induced in response to Fe toxicity, indicating their potential role in metal tolerance. Bioinformatics analysis showed that soybean MTP genes possessed a close relationship with certain Arabidopsis genes (i.e. ZAT, MTPB1) involved in solute transport and metal sequestration. Furthermore, top five motifs of soybean MTP protein correspond to the cation efflux family exhibited strong amino acid and evolutionary similarities with Arabidopsisthaliana. These findings shed light on Fe homeostasis mechanisms in soybean and could be used to regulate Fe uptake through breeding or transgenic manipulations of MTP genes.

Keywords: Cation efflux family; Fe homeostasis; Phylogenetic relationship; Soybean; Transcript.

MeSH terms

Gene Expression Regulation, Plant
Glycine max* / genetics
Glycine max* / metabolism
Iron* / metabolism
Plant Breeding
Plant Roots / genetics
Plant Roots / metabolism

Substances

Iron