Lopes M A, Takasaki K, Bostwick D E, Helentjaris T, Larkins B A
University of Arizona, Department of Plant Sciences, Tucson, USA.
Mol Gen Genet. 1995 Jun 10;247(5):603-13. doi: 10.1007/BF00290352.
Genetic modifiers of opaque2 convert the soft, starchy endosperm of opaque2 maize mutants to a hard, vitreous phenotype, while maintaining the enhanced lysine content of the grain. Genetic analysis of F2 segregating seeds from crosses of opaque2 by modified opaque2 genotypes indicated that the modifiers are complex traits that act codominantly. We developed two different segregating F2 populations and mapped the modifier loci by restriction fragment length polymorphism (RFLP) analysis. A relationship was found between formation of vitreous endosperm and the locus encoding the gamma-zein storage protein, which maps near the centromere of chromosome 7. Endosperm modification was consistently associated with the presence of two rather than one gamma-zein gene at this locus. A second modifier locus was mapped near the telomere of chromosome 7L.
opaque2的遗传修饰因子可将opaque2玉米突变体的柔软、粉质胚乳转变为坚硬的玻璃质表型，同时保持籽粒中赖氨酸含量的增加。对opaque2与改良opaque2基因型杂交产生的F2分离种子进行遗传分析表明，这些修饰因子是共显性作用的复杂性状。我们开发了两个不同的分离F2群体，并通过限制性片段长度多态性（RFLP）分析对修饰基因座进行定位。发现玻璃质胚乳的形成与编码γ-玉米醇溶蛋白贮藏蛋白的基因座之间存在关联，该基因座位于7号染色体着丝粒附近。胚乳修饰始终与该基因座上存在两个而非一个γ-玉米醇溶蛋白基因相关。第二个修饰基因座定位于7L染色体的端粒附近。
