Genomic transition to pathogenicity in chytrid fungi.
Genomic transition to pathogenicity in chytrid fungi.
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DOI：
10.1371/journal.ppat.1002338
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发表时间：
2011-11
期刊：
影响因子：
6.7
通讯作者：
Rosenblum EB
中科院分区：
文献类型：
--
作者：
Joneson S;Stajich JE;Shiu SH;Rosenblum EB
了解病原体出现的分子机制对于减轻新型传染病病原体的影响至关重要。壶菌水蛭壶菌（Batrachochytrium dendroatidis, Bd）是一种新兴的两栖动物病原体，与世界范围内两栖动物的衰退有关。Bd是其分支中唯一已知会攻击脊椎动物的成员。然而，关于Bd致病性的分子决定因素或进化过渡到致病性的分子决定因素知之甚少。在这里，我们对Bd最近的已知亲戚-一种非致病性多根同源壶菌（Hp）的基因组进行了测序。我们首先描述了Hp的基因组，它在大小和预测蛋白质的数量上与其他壶菌基因组相当。然后，我们比较了Hp、Bd和其他19种真菌的基因组，以确定Bd基因组中独特的或最近的进化元素。我们确定了1974个bd特异性基因，这是一个富含蛋白酶、脂肪酶和微生物效应基因本体术语的基因集。我们描述了三个Bd蛋白酶家族（金属蛋白酶、丝氨酸蛋白酶和天冬氨酸蛋白酶）的显著谱系特异性扩增。我们发现，这些蛋白酶基因家族的扩展发生在Bd和Hp从它们共同的祖先分化出来之后，因此定位于Bd分支。最后，我们证明蛋白酶基因家族扩展的时间早于Bd作为全球重要的两栖动物病原体的出现。壶菌水蛭壶菌（Batrachochytrium dendroatidis, Bd）是一种新兴的病原体，在世界范围内与大量两栖动物种群有关。Bd是一种已知会攻击脊椎动物的古老真菌（称为壶菌科）的唯一成员。研究一种杀死两栖动物的真菌是如何从非致病性的祖先进化而来的，这对于保护世界上现存的两栖动物免受Bd的侵害至关重要。我们对Bd最近的已知亲戚——一种名为多根同源壶菌（Homolaphlyctis polyrhiza, Hp）的非致病性壶菌的基因组进行了测序。我们比较了Bd、Hp和其他18种真菌的基因组，以确定Bd的独特之处。我们发现了大量的bd特异性基因，一组包含许多可能的致病因素的基因。特别是，我们描述了Bd基因组中的大量蛋白酶基因，并表明这些基因在Bd和Hp从它们的共同祖先分化后被复制。在进化背景下研究Bd的发病机制为蛋白酶基因在Bd杀伤两栖动物能力中的作用提供了新的证据。
Understanding the molecular mechanisms of pathogen emergence is central to mitigating the impacts of novel infectious disease agents. The chytrid fungus Batrachochytrium dendrobatidis (Bd) is an emerging pathogen of amphibians that has been implicated in amphibian declines worldwide. Bd is the only member of its clade known to attack vertebrates. However, little is known about the molecular determinants of - or evolutionary transition to - pathogenicity in Bd. Here we sequence the genome of Bd's closest known relative - a non-pathogenic chytrid Homolaphlyctis polyrhiza (Hp). We first describe the genome of Hp, which is comparable to other chytrid genomes in size and number of predicted proteins. We then compare the genomes of Hp, Bd, and 19 additional fungal genomes to identify unique or recent evolutionary elements in the Bd genome. We identified 1,974 Bd-specific genes, a gene set that is enriched for protease, lipase, and microbial effector Gene Ontology terms. We describe significant lineage-specific expansions in three Bd protease families (metallo-, serine-type, and aspartyl proteases). We show that these protease gene family expansions occurred after the divergence of Bd and Hp from their common ancestor and thus are localized to the Bd branch. Finally, we demonstrate that the timing of the protease gene family expansions predates the emergence of Bd as a globally important amphibian pathogen. The chytrid fungus Batrachochytrium dendrobatidis (Bd) is an emerging pathogen that has been implicated in decimating amphibian populations around the world. Bd is the only member of an ancient group of fungi (called the Chytridiomycota) that is known to attack vertebrates. The question of how an amphibian-killing fungus evolved from non-pathogenic ancestors is vital to protecting the world's remaining amphibians from Bd. We sequenced the genome of Bd's closest known relative - a non-pathogenic chytrid named Homolaphlyctis polyrhiza (Hp). We compared the genomes of Bd, Hp and 18 additional fungi to identify what makes Bd unique. We identified a large number of Bd-specific genes, a gene set that contains a number of possible pathogenicity factors. In particular, we describe a large number of protease genes in the Bd genome and show that these genes were duplicated after the divergence of Bd and Hp from their common ancestor. Studying Bd's pathogenesis in an evolutionary context provides new evidence for the role of protease genes in Bd's ability to kill amphibians.
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影响因子：
2.8
作者：
Brunke, S;Hube, B
通讯作者：
Hube, B
影响因子：
2.8
作者：
Longcore, JE;Pessier, AP;Nichols, DK
通讯作者：
Nichols, DK
DOI：
10.1073/pnas.0611195104
发表时间：
2007-05-01
影响因子：
11.1
作者：
Kaur, Rupinder;Ma, Biao;Cormack, Brendan P.
通讯作者：
Cormack, Brendan P.
DOI：
10.1073/pnas.0506889103
发表时间：
2006-02-28
影响因子：
11.1
作者：
Lips, KR;Brem, F;Collins, JP
通讯作者：
Collins, JP
影响因子：
2.6
作者：
da Silva, Bianca Alcantara;dos Santos, Andr Luis Souza;Pinto, Marcia Ribeiro
通讯作者：
Pinto, Marcia Ribeiro