Table of Contents
International Journal of Plant Genomics
Volume 2012, Article ID 514398, 11 pages
http://dx.doi.org/10.1155/2012/514398
Research Article

Poor Homologous Synapsis 1 Interacts with Chromatin but Does Not Colocalise with ASYnapsis 1 during Early Meiosis in Bread Wheat

School of Agriculture, Food & Wine, Waite Research Institute, The University of Adelaide, Waite Campus, PMB1, Glen Osmond, SA, 5064, Australia

Received 29 September 2011; Revised 25 November 2011; Accepted 30 November 2011

Academic Editor: Sylvie Cloutier

Copyright © 2012 Kelvin H. P. Khoo et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Chromosome pairing, synapsis, and DNA recombination are three key processes that occur during early meiosis. A previous study of Poor Homologous Synapsis 1 (PHS1) in maize suggested that PHS1 has a role in coordinating these three processes. Here we report the isolation of wheat (Triticum aestivum) PHS1 (TaPHS1), and its expression profile during and after meiosis. While the TaPHS1 protein has sequence similarity to other plant PHS1/PHS1-like proteins, it also possesses a unique region of oligopeptide repeat units. We show that TaPHS1 interacts with both single- and double-stranded DNA in vitro and provide evidence of the protein region that imparts the DNA-binding ability. Immunolocalisation data from assays conducted using antisera raised against TaPHS1 show that TaPHS1 associates with chromatin during early meiosis, with the signal persisting beyond chromosome synapsis. Furthermore, TaPHS1 does not appear to colocalise with the asynapsis protein (TaASY1) suggesting that these proteins are probably independently coordinated. Significantly, the data from the DNA-binding assays and 3-dimensional immunolocalisation of TaPHS1 during early meiosis indicates that TaPHS1 interacts with DNA, a function not previously observed in either the Arabidopsis or maize PHS1 homologues. As such, these results provide new insight into the function of PHS1 during early meiosis in bread wheat.