Chourey P S, Nelson O E
Biochem Genet. 1976 Dec;14(11-12):1041-55. doi: 10.1007/BF00485135.
Evidence is presented to show that the Sh locus specifies sucrose synthetase in the developing endosperm of maize. The sh/sh/sh endosperm possesses less than 10% sucrose synthetase activity as compared to the normal Sh/sh/sh endosperm. The residual enzyme activity in five independently derived mutant genotypes is attributable to a protein molecule of different electrophoretic and immunochemical specificities that is presumably independent of the sh locus. Sucrose synthetase activity in the embryo in both the genotypes is electrophoretically indistinguishable from the one present in the mutant endosperm. Mutant endosperm has a reduced starch content as compared to the normal. This observation constitutes genetic evidence supporting a critical role for sucrose synthetase in starch biosynthesis.
有证据表明，在玉米发育中的胚乳中，Sh基因座决定蔗糖合成酶。与正常的Sh/sh/sh胚乳相比，sh/sh/sh胚乳的蔗糖合成酶活性不到10%。在五个独立衍生的突变基因型中的残余酶活性归因于一种具有不同电泳和免疫化学特异性的蛋白质分子，该分子可能独立于sh基因座。两种基因型的胚中的蔗糖合成酶活性在电泳上与突变胚乳中的酶活性无法区分。与正常胚乳相比，突变胚乳的淀粉含量降低。这一观察结果构成了支持蔗糖合成酶在淀粉生物合成中起关键作用的遗传学证据。
