A highly potential Zn biofortification tool: MTP1 in Triticum aestivum

Area of Science:

• Plant Molecular Biology
• Agricultural Science
• Nutritional Biochemistry

Background:

• Metal Tolerance Proteins (MTPs) are crucial for managing micronutrient homeostasis in plants.
• Zinc deficiency, or 'hidden hunger,' impacts global health, necessitating strategies like crop biofortification.
• Common wheat (Triticum aestivum) possesses MTP members with potential for improving zinc bioavailability.

Purpose of the Study:

• To identify and characterize MTP members in Triticum aestivum.
• To evaluate the function of TaMTP1-like genes in metal tolerance and accumulation.
• To assess the potential of specific TaMTP1-like genes for zinc biofortification in wheat.

Main Methods:

• Identification of 33 MTP members in Triticum aestivum.
• Heterologous expression of six TaMTP1-like genes in yeast mutants to assess zinc and cobalt tolerance.
• Subcellular localization and functional analysis of selected TaMTP1-like proteins in Arabidopsis and rice.
• Expression analysis of TaMTP1-D in wheat endosperm.

Main Results:

• Six TaMTP1-like genes were identified and functionally characterized in yeast, showing complementation of metal hypersensitivity.
• TaMTP1-A, TaMTP1-D, and TaMTP1.1-B were localized to the vacuole membrane.
• TaMTP1-D exhibited higher zinc resistance and greater expression in endosperm compared to other TaMTP1-like members, with lower cobalt resistance.

Conclusions:

• TaMTP1-D plays a significant role in zinc and cobalt homeostasis at the vacuole membrane.
• TaMTP1-D is a promising candidate gene for enhancing zinc content in wheat endosperm through biofortification.
• Targeting TaMTP1-D can improve wheat's nutritional value for addressing zinc deficiency without adverse cobalt accumulation.