Catalogue - HEMs

The HEM lines (Homozygous EMS Mutants) are lines randomly mutagenized by Ethyl-Methane Sulfonate and made homozygous or nearly-homozygous (Capilla-Perez et al., Frontiers in Plant Science, 2018). The first part of the collection (EH lines) was made homozygous through haplodiploidization (Ravi and Chan, Nature, 2010). EH lines are in a Col-0 glabra mutant background, exhibiting an absence of trichomes, to facilitate haploid selection. The glabra allele corresponds to the Hc1 reporter lines (Elmayan et al., The Plant Cell, 1998), which carry a transgene consisting of the viral 35S promoter fused to the bacterial uidA gene-encoding β-glucuronidase (GUS). Consequently, the EH lines of the HEM collection are transgenic plants and must be cultivated under appropriate conditions. The second and largest part of the collection (ES lines) is in the Col-0 wild-type background and was made nearly-homozygous through four generations of selfing (Single Seed Descent) after EMS mutagenesis; ES lines do not contain any transgene. In both cases, a line is composed of identical or nearly-identical plants. This collection can be used for forward genetic screens, looking either at a single plant per line, or at several plants to look at a more quantitative phenotype. Each line should contain 100-500 homozygous mutations that affect the sequence of a protein coding gene (amino-acid change, stop codon, loss of splicing sites).

NEW! The whole-genome sequences of the HEM lines are available (Carrère et al., 2024). The ATHEM web interface provides the community with the raw sequences, SNP calling results and a web interface to search for SNPs in given HEM lines or genes.