Point Mutations in Centromeric Histone Induce Post-zygotic Incompatibility and Uniparental Inheritance

PLoS Genet. 2015 Sep 9;11(9):e1005494. doi: 10.1371/journal.pgen.1005494. eCollection 2015 Sep.

Abstract

The centromeric histone 3 variant (CENH3, aka CENP-A) is essential for the segregation of sister chromatids during mitosis and meiosis. To better define CENH3 functional constraints, we complemented a null allele in Arabidopsis with a variety of mutant alleles, each inducing a single amino acid change in conserved residues of the histone fold domain. Many of these transgenic missense lines displayed wild-type growth and fertility on self-pollination, but exhibited frequent post-zygotic death and uniparental inheritance when crossed with wild-type plants. The failure of centromeres marked by these missense mutation in the histone fold domain of CENH3 reproduces the genome elimination syndromes described with chimeric CENH3 and CENH3 from diverged species. Additionally, evidence that a single point mutation is sufficient to generate a haploid inducer provide a simple one-step method for the identification of non-transgenic haploid inducers in existing mutagenized collections of crop species. As proof of the extreme simplicity of this approach to create haploid-inducing lines, we performed an in silico search for previously identified point mutations in CENH3 and identified an Arabidopsis line carrying the A86V substitution within the histone fold domain. This A87V non-transgenic line, while fully fertile on self-pollination, produced postzygotic death and uniparental haploids when crossed to wild type.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Substitution
  • Arabidopsis / genetics*
  • Centromere*
  • Codon
  • Genes, Plant
  • Haploidy
  • Histones / genetics*
  • Ovule
  • Point Mutation*
  • Pollen

Substances

  • Codon
  • Histones

Grant support

The project was funded by Rijk Zwaan Zaadteelt en Zaadhandel B.V. to the the regents of the University of California by research agreement 201016851. The funders had no role in study design, data collection and analysis, or preparation of the manuscript. Under the IP agreement associated with this grant, RZ had the right to delay publication for several months, but they did not invoke this right.