Inversion of the chromosomal region between two mating type loci switches the mating type in Hansenula polymorpha.
Inversion of the chromosomal region between two mating type loci switches the mating type in Hansenula polymorpha.
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DOI：
10.1371/journal.pgen.1004796
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发表时间：
2014-11
期刊：
影响因子：
4.5
通讯作者：
Kaneko Y
中科院分区：
文献类型：
--
作者：
Maekawa H;Kaneko Y
酵母的交配型是由交配型位点（MAT）上的基因型决定的。在同源（自育）酵母菌中，如酿酒酵母菌和乳酸克卢维菌，a和α交配类型之间的高效转换使交配成为可能。两个沉默的交配型磁带，除了一个活跃的MAT位点，是交配型转换机制的重要组成部分。本研究对多态麻（H. polymorpha，又称Ogataea polymorpha）交配型基因的结构和功能进行了研究。发现多态h基因组在同一染色体上含有两个MAT位点，MAT1和MAT2，它们相距约18 kb。mat1编码的α1指定α细胞的身份，而交配型基因不需要一个身份和交配。然而，mat1编码的α2和mat2编码的a1对减数分裂至关重要。当存在于SLA2和SUI1基因旁边时，MAT1或MAT2转录活跃，而另一个则被抑制。营养限制诱导MAT中间区反转，导致两个MAT位点的染色体位置交换，从而交换交配类型身份。反转缺陷突变体仅在相互交配时表现出严重的缺陷，表明这种反转是交配类型切换和同体化的机制。这种基于染色体反转的机制代表了一种新的交配类型转换形式，只需要两个MAT位点。酵母菌属的交配系统已经从嗜脂耶氏酵母（Yarrowia lipolytica）的异菌制进化到酿酒酵母（Saccharomyces cerevisiae）的同菌制。获得无声磁带是迈向同性恋的重要一步。然而，一些在获得沉默盒之前从共同祖先分化出来的酵母菌属物种也是同源的，包括多态菌。本文对多态黄蚕交配型位点（MAT）的结构和功能进行了研究，发现了两个MAT位点MAT1和MAT2。虽然MAT1同时包含a和α信息，但结果表明它具有MATα的功能。mata用MAT2表示，它与MAT1的距离为18 kb。MAT1或MAT2的功能抑制是在单个细胞中建立或α交配型身份所必需的。发现MAT1和MAT2的染色体位置影响它们的转录状态，只有一个位点保持活跃状态。MAT干预区域的反转导致两个MAT位点的切换，从而导致交配类型的同质性，这是同质性所必需的。这种基于染色体反转的机制代表了一种新的交配类型转换形式，它需要两个MAT位点，其中只有一个被表达。
Yeast mating type is determined by the genotype at the mating type locus (MAT). In homothallic (self-fertile) Saccharomycotina such as Saccharomyces cerevisiae and Kluveromyces lactis, high-efficiency switching between a and α mating types enables mating. Two silent mating type cassettes, in addition to an active MAT locus, are essential components of the mating type switching mechanism. In this study, we investigated the structure and functions of mating type genes in H. polymorpha (also designated as Ogataea polymorpha). The H. polymorpha genome was found to harbor two MAT loci, MAT1 and MAT2, that are ∼18 kb apart on the same chromosome. MAT1-encoded α1 specifies α cell identity, whereas none of the mating type genes were required for a identity and mating. MAT1-encoded α2 and MAT2-encoded a1 were, however, essential for meiosis. When present in the location next to SLA2 and SUI1 genes, MAT1 or MAT2 was transcriptionally active, while the other was repressed. An inversion of the MAT intervening region was induced by nutrient limitation, resulting in the swapping of the chromosomal locations of two MAT loci, and hence switching of mating type identity. Inversion-deficient mutants exhibited severe defects only in mating with each other, suggesting that this inversion is the mechanism of mating type switching and homothallism. This chromosomal inversion-based mechanism represents a novel form of mating type switching that requires only two MAT loci. The mating system of Saccharomycotina has evolved from the ancestral heterothallic system as seen in Yarrowia lipolytica to homothallism as seen in Saccharomyces cerevisiae. The acquisition of silent cassettes was an important step towards homothallism. However, some Saccharomycotina species that diverged from the common ancestor before the acquisition of silent cassettes are also homothallic, including Hansenula polymorpha. We investigated the structure and functions of the mating type locus (MAT) in H. polymorpha, and found two MAT loci, MAT1 and MAT2. Although MAT1 contains both a and α information, the results suggest that it functions as MATα. MAT a is represented by MAT2, which is located at a distance of 18 kb from MAT1. The functional repression of MAT1 or MAT2 was required to establish a or α mating type identity in individual cells. The chromosomal location of MAT1 and MAT2 was found to influence their transcriptional status, with only one locus maintained in an active state. An inversion of the MAT intervening region resulted in the switching of the two MAT loci and hence of mating type identity, which was required for homothallism. This chromosomal inversion-based mechanism represents a novel form of mating type switching that requires two MAT loci, of which only one is expressed.
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DOI：
10.1073/pnas.0304170101
发表时间：
2004-02-10
影响因子：
11.1
作者：
Butler, G;Kenny, C;Wolfe, KH
通讯作者：
Wolfe, KH
影响因子：
3
作者：
Jones, Stephen K., Jr.;Bennett, Richard J.
通讯作者：
Bennett, Richard J.
影响因子：
11.4
作者：
KITAMURA, K;SHIMODA, C
通讯作者：
SHIMODA, C
影响因子：
3.3
作者：
Haber, James E.
通讯作者：
Haber, James E.
DOI：
10.1073/pnas.83.5.1418
发表时间：
1986-03-01
影响因子：
11.1
作者：
HAGEN, DC;MCCAFFREY, G;SPRAGUE, GF
通讯作者：
SPRAGUE, GF