Allelic variation of soybean flower color gene W4 encoding dihydroflavonol 4-reductase 2

BMC Plant Biology

Research Article

Yoshinori Murai¹  Tsukasa Iwashina¹  Tito Rodriguez Torrico²  Fan Yan²  Shaokang Di²  Felipe Rojas Rodas²  Ryoji Takahashi³  Toyoaki Anai⁴ 

[1] Department of Botany, National Museum of Nature and Science, 305-0005, Tsukuba, Ibaraki, Japan;Graduate School of Life and Environmental Sciences, University of Tsukuba, 305-8518, Tsukuba, Ibaraki, Japan;Graduate School of Life and Environmental Sciences, University of Tsukuba, 305-8518, Tsukuba, Ibaraki, Japan;National Institute of Crop Science, 305-8518, Tsukuba, Ibaraki, Japan;Laboratory of Plant Genetics and Breeding, Faculty of Agriculture, Saga University, 840-8502, Honjo-machi, Saga, Japan;

关键词: Dihydroflavonol 4-reductase;    Flavonoid;    Flower color;    Glycine max;    Glycine soja;    Soybean;   

DOI  :  10.1186/1471-2229-14-58

 received in 2013-12-04, accepted in 2014-02-26,  发布年份 2014

来源: Springer

【 摘 要 】

BackgroundFlower color of soybean is primarily controlled by six genes, viz., W1, W2, W3, W4, Wm and Wp. This study was conducted to investigate the genetic and chemical basis of newly-identified flower color variants including two soybean mutant lines, 222-A-3 (near white flower) and E30-D-1 (light purple flower), a near-isogenic line (Clark-w4), flower color variants (T321 and T369) descended from the w4-mutable line and kw4 (near white flower, Glycine soja).ResultsComplementation tests revealed that the flower color of 222-A-3 and kw4 was controlled by the recessive allele (w4) of the W4 locus encoding dihydroflavonol 4-reductase 2 (DFR2). In 222-A-3, a single base was deleted in the first exon resulting in a truncated polypeptide consisting of 24 amino acids. In Clark-w4, base substitution of the first nucleotide of the fourth intron abolished the 5′ splice site, resulting in the retention of the intron. The DFR2 gene of kw4 was not expressed. The above results suggest that complete loss-of-function of DFR2 gene leads to near white flowers. Light purple flower of E30-D-1 was controlled by a new allele at the W4 locus, w4-lp. The gene symbol was approved by the Soybean Genetics Committee. In E30-D-1, a single-base substitution changed an amino acid at position 39 from arginine to histidine. Pale flowers of T369 had higher expression levels of the DFR2 gene. These flower petals contained unique dihydroflavonols that have not yet been reported to occur in soybean and G. soja.ConclusionsComplete loss-of-function of DFR2 gene leads to near white flowers. A new allele of the W4 locus, w4-lp regulates light purple flowers. Single amino acid substitution was associated with light purple flowers. Flower petals of T369 had higher levels of DFR2 gene expression and contained unique dihydroflavonols that are absent in soybean and G. soja. Thus, mutants of the DFR2 gene have unique flavonoid compositions and display a wide variety of flower color patterns in soybean, from near white, light purple, dilute purple to pale.

【 授权许可】

Unknown   
© Yan et al.; licensee BioMed Central Ltd. 2014. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.