Transactivation of anthocyanin biosynthetic genes following transfer of B regulatory genes into maize tissues

EMBO J. 1990 Aug;9(8):2517-22.

Abstract

The C1, B and R genes regulating the maize anthocyanin biosynthetic pathway encode tissue-specific regulatory proteins with similarities to transcriptional activators. The C1 and R regulatory genes are usually responsible for pigmentation of seed tissues, and the B-Peru allele of B, but not the B-I allele, can substitute for R function in the seed. In this study, members of the B family of regulatory genes were delivered to intact maize tissues by high velocity microprojectiles. In colorless r aleurones or embryos, the introduction of the B-Peru genomic clone or the expressed cDNAs of B-Peru or B-I resulted in anthocyanin-producing cells. Luciferase produced from the Bronze1 anthocyanin structural gene promoter was induced 100-fold when co-introduced with the expressed B-Peru or B-I cDNAs. This quantitative transactivation assay demonstrates that the proteins encoded by these two B alleles are equally able to transactivate the Bronze1 promoter. Analogous results were obtained using embryogenic callus cells. These observations suggest that one major contribution towards tissue-specific anthocyanin synthesis controlled by the various alleles of the B and R genes is the differential expression of functionally similar proteins.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Alleles
  • Anthocyanins / metabolism*
  • Base Sequence
  • Cell Line
  • Gene Expression Regulation*
  • Genes, Regulator*
  • Genes, Synthetic*
  • Genetic Complementation Test
  • Genetic Vectors
  • Molecular Sequence Data
  • Mosaic Viruses / genetics
  • Mutation
  • Plant Proteins / genetics*
  • Plasmids
  • Promoter Regions, Genetic
  • Trans-Activators / genetics
  • Transfection*
  • Zea mays / genetics*

Substances

  • Anthocyanins
  • Plant Proteins
  • Trans-Activators