Lengeler Klaus B, Fox Deborah S, Fraser James A, Allen Andria, Forrester Keri, Dietrich Fred S, Heitman Joseph
Department of Molecular Genetics and Microbiology, Howard Hughes Medical Institute, Duke University, Durham, North Carolina 27710, USA.
Eukaryot Cell. 2002 Oct;1(5):704-18. doi: 10.1128/EC.1.5.704-718.2002.
The sexual development and virulence of the fungal pathogen Cryptococcus neoformans is controlled by a bipolar mating system determined by a single locus that exists in two alleles, alpha and a. The alpha and a mating-type alleles from two divergent varieties were cloned and sequenced. The C. neoformans mating-type locus is unique, spans >100 kb, and contains more than 20 genes. MAT-encoded products include homologs of regulators of sexual development in other fungi, pheromone and pheromone receptors, divergent components of a MAP kinase cascade, and other proteins with no obvious function in mating. The alpha and a alleles of the mating-type locus have extensively rearranged during evolution and strain divergence but are stable during genetic crosses and in the population. The C. neoformans mating-type locus is strikingly different from the other known fungal mating-type loci, sharing features with the self-incompatibility systems and sex chromosomes of algae, plants, and animals. Our study establishes a new paradigm for mating-type loci in fungi with implications for the evolution of cell identity and self/nonself recognition.
新型隐球菌这种真菌病原体的性发育和毒力由一个双极性交配系统控制，该系统由存在于两个等位基因（α和a）中的单个基因座决定。来自两个不同变种的α和a交配型等位基因被克隆并测序。新型隐球菌交配型基因座很独特，跨度超过100 kb，包含20多个基因。MAT编码的产物包括其他真菌中性发育调节因子的同源物、信息素和信息素受体、MAP激酶级联反应的不同组分，以及其他在交配中无明显功能的蛋白质。交配型基因座的α和a等位基因在进化和菌株分化过程中发生了广泛重排，但在遗传杂交和群体中是稳定的。新型隐球菌交配型基因座与其他已知的真菌交配型基因座显著不同，与藻类、植物和动物的自交不亲和系统及性染色体具有共同特征。我们的研究为真菌中的交配型基因座建立了一个新范例，对细胞身份及自我/非自我识别的进化具有启示意义。
