A complex arrangement of genes at a starch branching enzyme I locus in the D-genome donor of wheat.
A complex arrangement of genes at a starch branching enzyme I locus in the D-genome donor of wheat.
复制标题
小麦 D 基因组供体中淀粉分支酶 I 基因座的复杂基因排列。
作者：
S. Rahman;S. Abrahams;D. Abbott;Y. Mukai;M. Samuel;M. Morell;R. Appels
来自小麦D基因组供体节节麦（Triticum tauschii）的基因组DNA片段携带淀粉分支酶I（SBE I）型基因，其特征在于。一个片段在16 kb的DNA中含有一个完整的基因和两个部分基因。其中一个部分基因与另外两个部分基因的方向相反。完整的基因被测序。它的结构与水稻的结构非常相似，因为外显子3-8以相似的大小和间距保留。一个与完整基因紧密对应的cDNA被分离并鉴定;它编码一种推定的蛋白质，代表一种新型的SBE I，因为它在3'端比迄今为止在其他植物中报道的形式短。第二基因组片段含有不同的SBE I基因。小麦中SBE Ⅰ型基因约有10个拷贝，T. tauschii），其中大部分属于第7组染色体。原位杂交表明，一个主要的基因座位于染色体7 D的短臂的远端。
Genomic DNA fragments from Triticum tauschii (D-genome donor to wheat) carrying starch branching enzyme I (SBE I) type genes have been characterized. One fragment contains one complete gene and two partial genes in 16 kb of DNA. One of the partial genes is oriented in the opposite strand to the other two. The gene that is complete was sequenced. Its structure corresponds closely to that of rice in that exons 3-8 are retained at similar sizes and spacings. A cDNA closely corresponding to the complete gene was isolated and characterized; it codes for a putative protein that represents a novel type of SBE I, as it is shorter at the 3' end than the forms reported so far in other plants. A second genomic fragment contains a different SBE I gene. There appear to be approximately 10 copies of SBE I type genes in wheat (approximately 5 in T. tauschii) and most of them have been assigned to group 7 chromosomes. In situ hybridization indicates that a major locus for the genes is located at the distal end of the short arm of chromosome 7D.