基于基因组数据解析金耳A和B交配型位点结构  

Analyses of the A and B mating-type locus structure from Naematelia aurantialba based on genomic data

作　　者：沈真辉 曹瑶 李梦杰 杨林雷 罗祥英 李荣春 SHEN Zhenhui;CAO Yao;LI Mengjie;YANG Linlei;LUO Xiangying;LI Rongchun(Yunnan Junshijie Biotechnology Co.Ltd.,Kunming 650200,Yunnan,China;Institute of Edible Fungi,Yunnan Agricultural University,Kunming 650201,Yunnan,China)

机构地区：[1]云南菌视界生物科技有限公司,云南昆明650200 [2]云南农业大学食用菌研究所,云南昆明650201

出　　处：《菌物学报》2024年第2期16-37,共22页Mycosystema

基　　金：国家自然科学基金-云南联合项目(U1802231)。

摘　　要：金耳Naematelia aurantialba是我国特有的一种稀有银耳目胶体食用菌,因优异的营养价值和生物活性而常被用作传统药物和食品。它属于四极性异宗结合担子菌,但其交配型位点结构仍未被解析。本研究利用二代测序技术对4种不同交配类型的金耳单核菌株基因组进行重测序,通过生物信息学方法找到了金耳的A和B交配型位点并与其他大型真菌进行比较。结果显示4个单核体中含有2种A交配型位点和2种B交配型位点;其中2种A交配型位点都包含一对HD1和HD2基因,以典型的“头对头”方式排列,位点上下游基因的共线性较高,以脑状耳包革Naematelia encephala最高,在上下游具有保守的氧化还原酶基因和PRL22基因,而mip和β-fg基因不位于HD基因两侧,不存在紧密连锁关系。2种B交配型位点均含有1个信息素受体(STE3)和1个信息素前体基因(phB),比较B1和B2位点发现,B1位点的STE3和phB基因紧密排列,在phB上游紧密相邻着1个B2位点没有的RVT_1基因,在B2位点中STE3和phB基因之间插入了3个基因,其中STE12基因在B1位点没有,与其他真菌相比,B位点共线性较差,表明不同真菌中B位点变异性较大;在4个单核体中均含有信息素受体NaSTE3-3基因,但在其上下游未发现信息素前体基因,并与B交配型位点不在同一contig上。本研究获得的结果将有助于诠释金耳交配型位点结构,为今后遗传育种提供了理论依据。Naematelia aurantialba,a rare jelly edible fungus of the Tremellales order,is endemic to China and is often used as traditional medicine and food due to its exceptional nutritional value and biological activity.It is a heterothallic basidiomycete with a tetrapolar mating system.However,the structures of mating loci have not been characterized.In this study,the genome of four different mating types of monokaryotic strains of N.aurantialba was sequenced by second generation sequencing technology,and mating type A and B loci were searched and compared with those of other macrofungi by bioinformatics method based on genomic data.The results showed that there were two A mating-type loci and two B mating-type loci in these monokaryons.All two A mating-type loci contain a pair of HD1 and HD2 genes arranged in a typical‘head-to-head’manner and the synteny of several genes’upstream and downstream of A loci was higher as compared with that of other fungi,including conserved Oxidoreductase and PRL22 genes.However,the mip and β-fg genes are not closely linked to the HD gene and are not located on both sides of it.All two B mating-type loci contain a pheromone receptor and a pheromone precursor gene.Upon comparison of the B1 and B2 loci,it was discovered that the STE3 and phB genes at the B1 locus were situated in close proximity with one RVT_1 gene located upstream of phB.In contrast,at the B2 locus,three genes were inserted between the STE3 and phB genes,and the STE12 gene was absent from the B1 locus.Compared with B loci in other fungi,the synteny of B loci was poor,indicating that B loci were highly variable in different fungi.The gene for the pheromone receptor NaSTE3-3 is present in all four monokaryons,however,the gene for the pheromone precursor is not located in upstream or downstream,and the B mating type site is not present on the same contig.These results obtained would help us to understand the mating locus structures of N.aurantialba,being helpful to genetic breeding of this mushroom.

关 键 词：金耳 单核菌株 基因组 A交配型位点 B交配型位点 序列分析 

分 类 号：S567.34[农业科学—中草药栽培]