Genetic architecture of zinc hyperaccumulation in Arabidopsis halleri: the essential role of QTL × environment interactions

Abstract

Summary• This study sought to determine the main genomic regions that control zinc (Zn) hyperaccumulation in Arabidopsis halleri and to examine genotype · environment effects on phenotypic variance. To do so, quantitative trait loci (QTLs) were mapped using an interspecific A. halleri · Arabidopsis lyrata petraea F 2 population.• The F 2 progeny as well as representatives of the parental populations were cultivated on soils at two different Zn concentrations. A linkage map was constructed using 70 markers.• In both low and high pollution treatments, zinc hyperaccumulation showed high broad-sense heritability (81.9 and 74.7%, respectively). Five significant QTLs were detected: two QTLs specific to the low pollution treatment (chromosomes 1 and 4), and three QTLs identified at both treatments (chromosomes 3, 6 and 7). These QTLs explained 50.1 and 36.5% of the phenotypic variance in low and high pollution treatments, respectively. Two QTLs identified at both treatments (chromosomes 3 and 6) showed significant QTL · environment interactions.• The QTL on chromosome 3 largely colocalized with a major QTL previously identified for Zn and cadmium (Cd) tolerance. This suggests that Zn tolerance and hyperaccumulation share, at least partially, a common genetic basis and may have simultaneously evolved on heavy metal-contaminated soils.

Mapping QTL associated with remobilization of zinc from vegetative tissues into grains of barley (Hordeum vulgare)

“…4), suggest a complex nature of the traits and possibilities of QTL interactions with environment and QTL × QTL interactions (van Eeuwijk et al 2010;Frérot et al 2010). Therefore, QTL controlling Zn remobilization should be tested in different environments for specific metabolic processes responsible for variable Zn remobilization, such as expression of nicotianamine synthase.…”

CATION EXCHANGER1 Cosegregates with Cadmium Tolerance in the Metal Hyperaccumulator Arabidopsis halleri and Plays a Role in Limiting Oxidative Stress in Arabidopsis Spp.

“…These markers were selected to cover the CdTol2 region according to their position in the A. thaliana genome. The unique microsatellite marker was developed as described by Frérot et al (2010). Resequencing data were used to design the two SNP markers.…”

“…Within regions of interest, the criteria used for the selection of SNPs were (1) frequency of the polymorphism in A. halleri and A. lyrata equal to one, (2) 50 base flanking regions with low polymorphism within A. halleri and between A. halleri and A. lyrata, and (3) read depth .20. BC1 individuals from the study by Courbot et al (2007) were genotyped for the microsatellite according to the work by Frérot et al (2010) and the SNPs using competitive allele-specific PCR Kompetitive Allele Specific PCR genotyping system (KASP) chemistry (LGC Genomics). KASP assays were performed in a final reaction volume of 8 mL containing 4 mL of KASP Master Mix V2 Low ROX (LGC Genomics), 0.125 mL of KASP Mix Assay (LGC Genomics), and approximately 100 ng of genomic DNA.…”

“…Four of these markers are described in the previous paragraph. The four other microsatellite markers (Supplemental Table S1) were developed and genotyped according to the work by Frérot et al (2010). For map construction and QTL mapping, we used the same procedure as above.…”

Prediction of the edaphic factors influence upon the copper and cobalt accumulation in two metallophytes using copper and cobalt speciation in soils

“…Only a few species around the world (mostly Brassicaceae), are considered as constitutive hyperaccumulators. These species show that all populations have very high foliar metal concentrations irrespective of metal concentration in soil, including Noccaea caerulescens (Dechamps et al 2007), Arabidopsis halleri (Frerot et al 2010) and Gomphrena claussenii (Villafort Carvalho et al 2013) (zinc and cadmium hyperaccumulators); as well as several Alyssum species (nickel hyperaccumulator) (Brooks and Radford 1978;Brooks et al 1979;Broadley et al 2001;Hanikenne and Nouet 2011). Most of metallophytes are defined as facultative hyperaccumulators, which means that populations or individuals are hyperaccumulators and some are not (Pollard et al 2002).…”