A Gene Encoding a DUF247 Domain Protein Cosegregates with the S Self-Incompatibility Locus in Perennial Ryegrass

Authors Organisations
Type Article
Original languageEnglish
Pages (from-to)870-884
Number of pages15
JournalMolecular Biology and Evolution
Volume33
Issue number4
Early online date10 Dec 2015
DOI
Publication statusPublished - 10 Mar 2016
Links
Show download statistics
View graph of relations
Citation formats

Abstract

The grass family (Poaceae), the fourth largest family of flowering plants, encompasses the most economically important cereal, forage, and energy crops, and exhibits a unique gametophytic self-incompatibility (SI) mechanism that is controlled by at least two multiallelic and independent loci, S and Z. Despite intense research efforts over the last six decades, the genes underlying S and Z remain uncharacterized. Here, we report a fine-mapping approach to identify the male component of the S-locus in perennial ryegrass (Lolium perenne L.) and provide multiple evidence that a domain of unknown function 247 (DUF247) gene is involved in its determination. Using a total of 10,177 individuals from seven different mapping populations segregating for S, we narrowed the S-locus to a genomic region containing eight genes, the closest recombinant marker mapping at a distance of 0.016 cM. Of the eight genes cosegregating with the S-locus, a highly polymorphic gene encoding for a protein containing a DUF247 was fully predictive of known S-locus genotypes at the amino acid level in the seven mapping populations. Strikingly, this gene showed a frameshift mutation in self-compatible darnel (Lolium temulentum L.), whereas all of the self-incompatible species of the Festuca–Lolium complex were predicted to encode functional proteins. Our results represent a major step forward toward understanding the gametophytic SI system in one of the most important plant families and will enable the identification of additional components interacting with the S-locus.

Keywords

  • Domain of unknown function (DUF) 247, Fine-mapping, Perennial ryegrass (Lolium perenne L.), Self-incompatibility (SI), RNA sequencing (RNAseq), S-locus