Submitted to: Journal of Heredity
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/15/2002
Publication Date: 12/1/2002
Citation: Stinard, P.S., Sachs, M.M. 2002. The identification and characterization of two dominant R1 haplotype-specific inhibitors of aleurone color in Zea mays. Journal of Heredity. 93(6):421-428. DOI: 10.1093/jhered/93.6.421.
Interpretive Summary: 1) Rationale: One important aim of basic research in crop plants is to gain greater insight as to how genes function and interact. The goal of this study was to characterize factors affecting kernel color in maize. 2) Accomplishments: The results show that inhibitor factors can repress certain variations of a regulatory gene known as 'r1'. This in turn inhibits kernel color. 3) Significance: The understanding of this interaction between genes will give us a greater comprehension of gene regulation in crop plants. This in turn can lead to better knowledge of methods to improve crop plants.
Technical Abstract: We report the identification and characterization of two novel dominant inhibitors of aleurone color in Zea mays that interact with specific haplotypes of the r1 locus. One inhibitor locus, inr1 (inhibitor of r1 aleurone color1), maps to the long arm of chromosome 10, distal to the TB-10L19 breakpoint and tightly linked to dull1, and the second inhibitor locus, inr2 (inhibitor of r1 aleurone color2), maps to the long arm of chromosome 9. Dominant inhibitory alleles of inr1 and inr2 act by suppressing aleurone color conditioned by certain r1 haplotypes. Two haplotypes, R1 ch:Stadler and R1-Randolph, exhibit nearly complete suppression of aleurone color in the presence of inhibitory alleles of inr1 or inr2. Two members of the R1 d class of haplotypes, R1 d:Catspaw and R1 d:Arapaho, show partial suppression. Other haplotypes tested were not visibly affected. The response of r1 haplotypes to inhibitory inr1 and inr2 alleles provides another means of analyzing the complex behavior of the seed color components of r1 haplotypes. Possible mechanisms of action of inr1 and inr2 are discussed.