Polymorphisms in the α-amy1 gene of wild and cultivated barley revealed by the polymerase chain reaction
Polymorphisms in the α-amy1 gene of wild and cultivated barley revealed by the polymerase chain reaction
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DOI：
10.1007/bf00225388
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发表时间：
1994-10
影响因子：
5.4
通讯作者：
S. Weining;L. Ko;R. Henry
中科院分区：
文献类型：
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作者：
S. Weining;L. Ko;R. Henry
α-淀粉酶是植物中参与淀粉水解的关键酶。利用聚合酶链反应（PCR）技术，对大麦α-amy 1基因序列中两对引物的退火位点之间的扩增序列进行多态性检测。这两个引物（Bsw 1和Bsw 7），侧翼的启动子区和第一个外显子，扩增两个PCR片段在大麦。其中一个扩增产物预期长度为820 bp，与另一个约750 bp的较短PCR条带一起出现。这一750 bp的片段似乎来源于一个以前没有报道过的α-淀粉酶基因。这两个PCR产物都可以从供试的二棱大麦品种中扩增出来，包括从其中获得序列信息的喜马拉雅品种。五个六棱大麦品种也有两个PCR片段，而另外两个只有长片段。这两个片段似乎是大麦所特有的，它们都不能从其他谷物中扩增出来;例如，小麦，黑麦或高粱。利用小麦-大麦异附加系将这两个α-淀粉酶片段定位在α-淀粉酶基因6 H的长臂上。用引物Bsw 1和Bsw 7对野生大麦基因组DNA进行扩增，结果表明，两个片段可能同时存在，也可能同时存在长片段和短片段。结果还表明，这两个片段的基因在大麦中可能是相互独立的。这两个片段在二棱大麦品种中的保守带型表明，从这些基因中进行的人工选择可能在栽培大麦从野生大麦进化中发挥了重要作用。
α-Amylases are the key enzymes involved in the hydrolysis of starch in plants. The polymerase chain reaction (PCR) was used to detect polymorphisms in the length of amplified sequences between the annealing sites of two primers derived from publishedα-amy1gene sequences in barley. These two primers (Bsw1 and Bsw7), flanking the promoter region and the first exon, amplified two PCR fragments in barley. One of the amplified products, with the expected length of 820 bp, appeared together with another shorter PCR band of around 750 bp. This 750-bp fragment seems to be derived from anα-amylase gene not reported previously. Both of the PCR products could be amplified from the two-rowed barley varieties tested, including cv Himalaya from which the sequence information was obtained. Five of the six-rowed barley varieties also have the two PCR fragments whereas another two have only the long fragment. These two fragments seem to be unique to barley, neither of them could be amplified from other cereals; for example, wheat, rye or sorghum. These twoα-amylase fragments were mapped to the long arm of 6H, the location of theα-amy1genes, using wheat-barley addition lines. Amplification of genomic DNA from wild barley accessions with primers Bsw1 and Bsw7 indicated that both of the fragments could be present, or the long and short fragments could be present alone. The results also demonstrated that the genes specifying these two fragments could be independent from each other in barley. The conserved banding pattern of these two fragments in the two-rowed barley varieties implies that artificial selection from these genes may have played an important role in the evolution of cultivated barley from wild barley.