Plant and Cell Physiology Advance Access originally published online on September 14, 2008
Plant and Cell Physiology 2008 49(11):1723-1733; doi:10.1093/pcp/pcn143
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
orf260cra, a Novel Mitochondrial Gene, is Associated with the Homeotic Transformation of Stamens into Pistil-Like Structures (Pistillody) in Alloplasmic Wheat
1 Department of Bioscience, Fukui Prefectural University, Eiheiji-cho, Fukui, 910-1195 Japan
2 Department of Agrobioscience, Graduate School of Agricultural Science, Kobe University, 1-1 Rokkodai-cho, Nada-ku, Kobe, 657-8501 Japan
*Corresponding author: E-mail, murai{at}fpu.ac.jp; Fax, +81-776616000.
 |
Abstract |
|---|
Homeotic transformation of stamens into pistil-like structures (pistillody) can occur in cytoplasmic substitution (alloplasmic) lines of bread wheat (Triticum aestivum) that have the cytoplasm of the related species, Aegilops crassa. Previously we showed that pistillody results from altered patterns of expression of class B MADS-box genes mediated by mitochondrial gene(s) in the Ae. crassa cytoplasm. The wheat cultivar Chinese Spring does not show pistillody when Ae. crassa cytoplasm is introduced. The absence of an effect is due to a single dominant gene (designated Rfd1) located on the long arm of chromosome 7B. To identify the mitochondrial gene involved in pistillody induction, we performed a subtraction analysis using cDNAs derived from young spikes of a pistillody line and a normal line. We found that mitochondrial cDNA clone R04 was abundant in the young spikes of the pistillody line but was down-regulated in the normal line that carried nuclear Rfd1. Sequencing of the full-length cDNA corresponding to clone R04 showed that two genes were present, cox I (cytochrome c oxidase subunit I) and orf260cra. orf260cra shows high sequence similarity to orf256, the T. timopheevii mitochondrial gene responsible for cytoplasmic male sterility (CMS). orf260cra was also present in the cytoplasms of Ae. juvenalis and Ae. vavilovii, which induce pistillody, but not in the cytoplasms of other species not associated with pistillody. Furthermore, Western blot analysis revealed that the ORF260cra protein was more abundant in the pistillody line than in the normal line. We suggest therefore that orf260cra is associated with pistillody induction.
Keywords: Alloplasmic wheat - Cytoplasmic homeosis - Cytoplasmic male sterility - Mitochondrial gene - Pistillody
Abbreviations: AG, AGAMOUS; AP3, APETALA3; CMS, cytoplasmic male sterility; CS, Chinese Spring; N26, Norin 26; ORF, open reading frame; PCMS, photoperiod-sensitive cytoplasmic male sterility; PI, PISTILLATA; Rf, restorer of fertility; RT–PCR, reverse transcription–PCR; SEP, SEPALLATA; WAP3, wheat APETALA3; WPI, wheat PISTILLATA.
The nucleotide sequences of orf260cra and orf113cra in the Aegilops crassa mitochondrial genome have been submitted to the DDBJ/EMBL/GenBank under the accession numbers AB438956 [GenBank] and AB438957 [GenBank] , respectively
3Present address: Bioscience and Biotechnology Center, Nagoya University, Chikusa, Nagoya, 464-8601 Japan
4Present address: Department of Molecular Biology, Institute of Health Biosciences, The University of Tokushima Graduate School, Tokushima, 770-8504 Japan
(Received August 18, 2008; Accepted September 10, 2008)
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  Compiled by, F. Tooke, T. Chiurugwi, and N. Battey Flowering Newsletter bibliography for 2008 J. Exp. Bot., June 23, 2009; (2009) erp154v1. [Full Text] [PDF]
|
|