Submitted to: Plant and Animal Genome Conference Proceedings
Publication Type: Abstract only
Publication Acceptance Date: 12/1/2006
Publication Date: 1/12/2007
Citation: Xu, M., Battacharyya, M.K., Palmer, R.G. 2007. The w4-m allele in soybean [Glycine max (L.) Merr.] harbors an active transposable element. Plant and Animal Genome Conference Proceedings. Abstract No. P405. Interpretive Summary:
Technical Abstract: In soybean, the W4 locus is one of the loci that control anthocyanin biosynthesis of flowers and hypocotyls. A putative transposable element was suggested to reside within or adjacent to it in the mutable line T322 (w4-m). Levels of delphinidin or its derivates, the main pigments in soybean flowers, were much lower in flowers with reduced pigmentation. Reduced pigment levels are associated with the reduced steady state transcript levels or abnormal transcript sizes of the dihydroflavonol-4-reductase 2 (DFR 2) gene. RFLP analysis conducted with an F2 mapping population of the cross between Minsoy and T369 (w4-p) indicated that DFR2 is located in the W4 locus. The DFR2 gene was cloned from a BAC library. The open reading frame of DFR2 is 3311 bps long. It contains 6 exons and 5 introns. By using different regions of the cDNA of DFR2 as probe in Southern blot analysis, we have shown that there is an insertion in DFR2 intron 2 in the w4-mutable line T322 (w4-m). Transposition of this element caused wild-type revertants at the W4 locus and new mutations in other genes including DFR2 itself. For example, reinsertion of the element to the promoter or coding regions of the gene caused new mutant phenotypes such as dilute purple in T321, pale in T369, and light-pale white.