title: A MYB transcription factor controls flower color in soybean.
abstract: Purple-blue flower of soybean (Glycine max [L.] Merr.) is controlled by the W2 locus. Previous studies revealed that a MYB transcription factor gene GmMYB-G20-1 was located at a position similar to the W2 gene and that a base substitution generated a stop codon in the MYB domains of 2 soybean lines with purple-blue flowers. This study was conducted to confirm the relationship between GmMYB-G20-1 and the W2 gene. Cleaved amplified polymorphic sequence analysis to detect the base substitution suggested that a similar mutation occurred in 2 other soybean lines having purple-blue flowers, 037-E-8, and Yogetsu 1-blue. Thus, all genotypes having purple-blue flowers had identical base substitutions. To verify the function of GmMYB-G20-1, apple latent spherical virus (ALSV) vectors were constructed to perform virus-induced gene silencing of GmMYB-G20-1. A cultivar Harosoy with purple flowers (W2W2) was infected by the empty ALSV vector (wtALSV) or the GmMYB-G20-1-ALSV vector containing a fragment (nucleotide position 685-885) of GmMYB-G20-1. Plants infected by empty vectors had only purple flowers. In contrast, most flowers of plants infected with GmMYB-G20-1-ALSV had irregular gray/blue sectors in flower petals and some of the flowers had almost gray/blue petals. These results strongly suggest that silencing of GmMYB-G20-1 can alter flower color and that it may correspond to the W2 gene.
authors.affiliation: National Institute of Crop Science, Tsukuba, Ibaraki 305-8518, Japan. masako@affrc.go.jp
authors.forename: Ryoji
authors.initials: R
authors.lastname: Takahashi
authors.forename: Noriko
authors.initials: N
authors.lastname: Yamagishi
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Yoshikawa
mesh_terms: D018389:Codon, Nonsense / Q000235:genetics; D003433:Crosses, Genetic; D004591:Electrophoresis, Polyacrylamide Gel; D035264:Flowers / Q000235:genetics* / Q000502:physiology; D020868:Gene Silencing; D005822:Genetic Vectors / Q000235:genetics; D010858:Pigmentation / Q000235:genetics*; D013025:Glycine max / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*
chemical_list: D018389:Codon, Nonsense; D014157:Transcription Factors