The mating-type and pathogenicity locus of the fungus Ustilago hordei spans a 500-kb region
The mating-type and pathogenicity locus of the fungus Ustilago hordei spans a 500-kb region
复制标题
DOI：
10.1073/pnas.96.26.15026
复制
发表时间：
1999-12-21
影响因子：
11.1
通讯作者：
Kronstad, JW
中科院分区：
文献类型：
--
作者：
Lee, N;Bakkeren, G;Kronstad, JW
真菌病原菌Ustilago hordei引起大麦和燕麦的黑穗病。该菌的交配和致病力是由MAT基因座控制的，MAT基因座包含两个不同的基因复合体a和b。在本研究中，我们用限制性内切酶I-SCEL的识别序列标记了a和b区域，并确定了MAT-1菌株和MAT-2菌株的复合体之间的距离分别为500kb和430kb。A和b基因复合体中已知基因的组织结构特征为MAT-1和MAT-2之间的不同源性和序列倒置提供了证据，抗生素抗性标记也被用于标记MAT-1菌株(金霉素)中的a基因复合体和MAT-2菌株(潮霉素)中的b基因复合体，这些菌株与这些菌株杂交后，对这两种抗生素耐药的后代被以很低的频率回收，表明重组在MAT区域内受到抑制。总体而言，携带U，hordei的MAT基因座的染色体同源基因与原始的性染色体有共同的特征，另外还有一个特点，即MAT基因座也控制着致病性。
The fungal pathogen Ustilago hordei causes the covered smut disease of barley and oats. Mating and pathogenicity in this fungus are controlled by the MAT locus, which contains two distinct gene complexes, a and b, In this study, we tagged the a and b regions with the recognition sequence for the restriction enzyme I-Scel and determined that the distance between the complexes is 500 kb in a MAT-I strain and 430 kb in a MAT-2 strain. Characterization of the organization of the known genes within the a and b gene complexes provided evidence for nonhomology and sequence inversion between MAT-1 and MAT-2, Antibiotic-resistance markers also were used to tag the a gene complex in MAT-1 strains (phleomycin) and the b gene complex in MAT-2 strains (hygromycin), Crosses were performed with these strains and progeny resistant to both antibiotics were recovered at a very low frequency, suggesting that recombination is suppressed within the MAT region. Overall, the chromosome homologues carrying the MAT locus of U, hordei share features with primitive sex chromosomes, with the added twist that the MAT locus also controls pathogenicity.