[Fragment length polymorphism of Wx-B1 gene digested by BamHI and its relation to amylose content of wheat].
There are two types of starch, amylose and amylopectin of flour. Amylose content (AC) is significantly negatively correlated with noodle quality. The waxy gene (Wx) encodes the granule-bound starch synthase (GBSS, EC 3.4.1.11), or Wx protein, is responsible for the synthesis of amylose in wheat. Common wheat is allohexaploid, it has three different Wx proteins: Wx-A1, Wx-B1, and Wx-D1. Consequently, amylose content and pasting properties of starch were influenced by the lack of the Wx-B1 protein, followed by that of Wx-D1, and Wx-A1. Using STS (sequence-tagged sites) primers, the sequences were amplified near the 4th intron region, and fragments amplified were digested by BamHI in 35 wheat cultivars. The results indicate that some fragments can be digested and the other cannot. The fragments digested showed two length polymorphism, and the length is negatively correlated with amylose content. The fragment in many cultivars with amylose content above 20% can be digested by BamHI, while those with amylose content below 20% cannot. All these indices demonstrate that there is variation exists in amplified region of Wx-B1 gene. This can be useful in breeding program to select wheat cultivars with different amylose content, and improve wheat quality.
Wang
Fang
F
College of Life Sciences, Shangdong Agricultural University, Tai'an 271018, China.
Zhao
Hui
H
Wang
Yan
Y
Wang
Xian-Ze
XZ
D000688:Amylose / Q000378:metabolism*; D001483:Base Sequence; D018744:DNA, Plant / Q000235:genetics / Q000378:metabolism; D015245:Deoxyribonuclease BamHI / Q000378:metabolism*; D004586:Electrophoresis; D018506:Gene Expression Regulation, Plant; D007438:Introns / Q000235:genetics; D008969:Molecular Sequence Data; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D012150:Polymorphism, Restriction Fragment Length; D013214:Starch Synthase / Q000235:genetics* / Q000378:metabolism; D014908:Triticum / Q000235:genetics* / Q000378:metabolism
D018744:DNA, Plant; D010940:Plant Proteins; D000688:Amylose; D013214:Starch Synthase; D015245:Deoxyribonuclease BamHI