Abstract
Natural variation in the regulation of the accumulation of mineral nutrients and trace elements in plant tissues is crucial to plant metabolism, development, and survival across different habitats. Studies of the genetic basis of natural variation in nutrient metabolism have been facilitated by the development of ionomics. Ionomics is a functional genomic approach for the identification of the genes and gene networks that regulate the elemental composition, or ionome, of an organism. In this study, we evaluated the genetic basis of divergence in elemental composition between an inland annual and a coastal perennial accession of Mimulus guttatus using a recombinant inbred line (RIL) mapping population. Out of 20 elements evaluated, Mo and Cd were the most divergent in accumulation between the two accessions and were highly genetically correlated in the RILs across two replicated experiments. We discovered two major quantitative trait loci (QTL) for Mo accumulation, the largest of which consistently colocalized with a QTL for Cd accumulation. Interestingly, both Mo QTLs also colocalized with the two M. guttatus homologues of MOT1, the only known plant transporter to be involved in natural variation in molybdate uptake.
Highlights
Understanding natural genetic variation in the uptake, transport, and sequestration of mineral nutrients is crucial to determining how plants survive across different habitats
The major goals of this study were to: 1) Characterize trait correlations and divergence in elemental accumulation between inland annual and coastal perennial accessions of M. guttatus, 2) Discover quantitative trait loci (QTL) associated with the variation in the elemental accumulation, and 3) Determine if these QTLs colocalize with candidate genes that could be the targets of follow up fine-mapping and molecular studies
Four out of ionomic traits significantly differed between IM62 and DUN10 in the first experiment, while nine out of significantly differed in the second experiment (Table 1)
Summary
Understanding natural genetic variation in the uptake, transport, and sequestration of mineral nutrients is crucial to determining how plants survive across different habitats. Since individual plants only grow in one location for the entirety of their lives they must be able to cope with different levels of available mineral nutrients. Plants have evolved numerous mechanisms for regulation of the accumulation of nutrients. Natural variation in these processes appears to play an important role in plant growth [1]. Many of the mineral nutrient and trace elements accumulated by specific plant tissues appear to be regulated in a coordinated fashion [2,3]. With the coupling of high-throughput multi-element (ionomic) analytical techniques, such as Inductively Coupled Plasma-Mass Spectroscopy (ICP-MS) with genome-enabled genetics, it is possible to efficiently study the genetic mechanisms involved in controlling these multiple element regulatory networks [4,5,6]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
