DEVELOPMENTAL DIFFERENCES IN ACTION OFRANDBALLELES IN MAIZE

Abstract

Alleles of the B and R loci collec:ed from different geographic races of maize differ with respect to concentration, pattern, and tissue specificity of anthocyanin formation. No differences were found between the pigments formed by B action and those formed by R action. The activities of four B alleles and five R alleles when compared in a common genetic background and described in terms of the whole life cycle show differences in the following respects: In a given tissue, for example the aleurone, there are differences in a ) rate of activity, b) time of onset of activtiy, c) time that activity ceases. Apparent tissue specificity is shown when the development of a tissue coincides with the period during which the gene is active. True tissue specificity is shown by alleles that have different activities in tissues that develop at the same time. This latter type of specificity was shown only by alleles known to consist of more than one synaptically homologous region, or by those derived in some way from such complex alleles. It is suggested that for most genetic systems there probably exists potential for change in level of action, change in time of onset and termination of activity, and change toward tissue specificity. The type and extent of the change tolerated will depend on the system involved.

Silencing CHALCONE SYNTHASE in Maize Impedes the Incorporation of Tricin into Lignin and Increases Lignin Content

“…Seed stocks of these lines were obtained from the James Birchler laboratory (University of Missouri). The C2-Idf allele was in a B; Pl; R-scm2 W22 background, where B stands for the B-I allele conditioning pigmentation (Goff et al, 1990), Pl stands for the Pl-Rhoades (Pl-Rh) allele (the Pl-Rh allele is highly expressed and produces strong pigmentation in most tissues of the maize plant; Hollick et al, 1995), and R-scm2 stands for an R allele that conditions anthocyanin pigmentation in the embryo and endosperm of the kernel (Styles et al, 1973). The C2; B; Pl; R-scm2 W22 (C2 control) was generated by crossing a full-color C2; b; pl; R-scm2 W22 inbred stock with a C2; B; Pl; r-g W22 inbred stock.…”

Nuclear Targeting of the Maize R Protein Requires Two Nuclear Localization Sequences

“…However, the possibility exists that these multiple NLSs function at different developmental stages. Another possibility is that multiple NLSs are required in the R protein to regulate tissue-specific expression because different alleles of the R gene are expressed in different tissues (Styles et al, 1973;Coe, 1985). The Lc allele used in this study is expressed in a number of tissues, including pericarp, ligule, midribs, coleoptiles, anthers, silks, and brace roots; whereas another allele of R, R-nj, is expressed only in the scutellum, coleoptiles, and brace roots.…”

Identification of functional domains in the maize transcriptional activator C1: comparison of wild-type and dominant inhibitor proteins.

“…For example, the regulatory genes B (Styles et al 1973) and Pi (Gerats et al 1984) are required for pigmentation in most of the plant body, although strong light can partially overcome the requirement for PI (Coe et al 1988). Cl is required for pigmentation of the aleurone and the embryo but is not required in the plant body (Chen and Coe 1977;Coe 1985).…”

“…Cl is required for pigmentation of the aleurone and the embryo but is not required in the plant body (Chen and Coe 1977;Coe 1985). A functional R gene product is required for anthocyanin pigmentation in the aleurone, anthers, and coleoptile (Styles et al 1973), although the B-Peru allele of B can substitute for R in the aleurone (Styles et al 1973). The Rscm2 allele of R conditions anthocyanin pigmentation in the maize embryo (Styles et al 1973).…”

“…A functional R gene product is required for anthocyanin pigmentation in the aleurone, anthers, and coleoptile (Styles et al 1973), although the B-Peru allele of B can substitute for R in the aleurone (Styles et al 1973). The Rscm2 allele of R conditions anthocyanin pigmentation in the maize embryo (Styles et al 1973). r or b mutations have been found to affect the levels of the mRNAs and/or enzymes encoded by some of the anthocyanin structural genes examined (Dooner and Nelson 1979;Dooner 1983;Chandler et al 1989;Ludwig et al 1989).…”