The Salt lab recently published a paper in PLoS Genetics in which we describe the use of GWA mapping to identify HMA3 as the primary locus controlling natural variation in foliar accumulation of Cd in Arabidopsis thaliana. The paper can be read at http://www.plosgenetics.org/article/info%3Adoi%2F10.1371%2Fjournal.pgen.1002923 and the abstract can be seen below.
Abstract: Understanding the mechanism of cadmium (Cd) accumulation in plants is
important to help reduce its potential toxicity to both plants and
humans through dietary and environmental exposure. Here, we report on a
study to uncover the genetic basis underlying natural variation in Cd
accumulation in a world-wide collection of 349 wild collected
Arabidopsis thaliana accessions. We identified a 4-fold variation (0.5-2
µg Cd g(-1) dry weight) in leaf Cd accumulation when these accessions
were grown in a controlled common garden. By combining genome-wide
association mapping, linkage mapping in an experimental F2 population,
and transgenic complementation, we reveal that HMA3 is the sole major
locus responsible for the variation in leaf Cd accumulation we observe
in this diverse population of A. thaliana accessions. Analysis of the
predicted amino acid sequence of HMA3 from 149 A. thaliana accessions
reveals the existence of 10 major natural protein haplotypes.
Association of these haplotypes with leaf Cd accumulation and genetics
complementation experiments indicate that 5 of these haplotypes are
active and 5 are inactive, and that elevated leaf Cd accumulation is
associated with the reduced function of HMA3 caused by a nonsense
mutation and polymorphisms that change two specific amino acids.
The latest news about the ionomics project and thoughts from team members.
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