Phenotypic abnormalities of fr , sp , and och-1 single mutants are suppressed by loss of putative GPI-phospholipase A2 in Neurospora crassa
Phenotypic abnormalities of fr , sp , and och-1 single mutants are suppressed by loss of putative GPI-phospholipase A2 in Neurospora crassa
复制标题
粗糙脉孢菌中推定的 GPI-磷脂酶 A2 的丢失抑制了 fr 、 sp 和 och-1 单突变体的表型异常
DOI：
10.1016/j.myc.2016.12.002
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发表时间：
2017
期刊：
影响因子：
1.4
通讯作者：
Fujimura Makoto
中科院分区：
文献类型：
--
作者：
Kamei Masayuki;Tsukagoshi Yuko;Banno Shinpei;Ichiishi Akihiko;Fukumori Fumiyasu;Fujimura Makoto
钙离子（Ca ~（2+））是丝状真菌菌丝生长和发育所必需的。模式丝状真菌粗糙脉孢菌（Neurospora crassa）在菌丝生长过程中，依靠内部产生的Ca ~（2+）梯度来维持极性生长，表明丝状形态受胞内Ca ~（2+）梯度和钙信号因子的控制（杰克逊和希思，1993; Levina等人，1995; Prokisch等人，1997; Alcantara-Sanchez等人，2004; Bowman等人，2011; Riquelme等人，2011）。钙信号传导因子，如钙/钙调素依赖性激酶，响应细胞溶质游离Ca 2+浓度的变化，已在N. crassa（Tamuli et al. 2013; Kumar and Tamuli 2014）。菌丝体尖端中的急性Ca 2+梯度由拉伸激活的磷脂酶C产生，其产生三磷酸肌醇，其激活离子通道以在尖端释放Ca 2+（Silverman-Gavrila和Lew 2001，2003）。N. crassa（plc-1和splA 2）显示出响应于由Ca 2+离子载体A23187诱导的Ca 2+浓度增加的生长缺陷（Barman和Tamuli 2015）。此外，一些研究表明，Ca 2+介导的信号也调节真菌趋触性，即菌丝对机械刺激的生长反应。这种现象已在真菌中广泛观察到，如白色念珠菌（Brand and and Gow 2009; Brand et al. 2009）、尼日尔曲霉（Fischer et al. 2008）、稻瘟病菌（Magnaporthe grisea）（Tucker and塔尔博特2001）和稻瘟病菌（N. crassa（Bowman等人，2011，2012）。对N.据报道，crassa显示出显著较低的生长速率和可通过外源Ca 2+恢复的超支化菌丝体表型（Dicker和Turian 1990; Sone和Griffiths 1999; Bok等2001）。fr是S.酿酒酵母CDC 1基因，其编码通过调节内质网中的胞质Mn 2+水平参与钙信号传导的必需脂质磷酸酶Cdc 1（Rossanese et al. 2001; Losev et al. 2008）。CDC 1突变体对温度敏感，在限制性温度下细胞内Ca 2+水平升高（Loukin和Kung 1995; Paidhungat和加勒特1998 a，B; Losev等人2008）。这种CDC 1相关表型通过PER 1的缺失而受到抑制（Losev et al. 2008）。酿酒酵母Per 1作为磷脂酶A2样蛋白发挥功能，其是糖基磷脂酰肌醇（GPI）重塑途径所需的。Per 1的缺失可能会损害GPI锚定蛋白与膜的结合，并改变酵母中GPI锚定物中的磷脂酰肌醇部分（Fujita et al. 2006）。了N. crassa fr突变体对Mn 2+和钙调磷酸酶抑制剂FK 506都具有更高的敏感性（Sone和Griffiths 1999），表明FROST有助于Mn 2+稳态和钙信号传导。另一个N。crassa基因，sp，是丝状真菌特异性基因，编码SPRAY，一种假定的钙离子通道蛋白;然而，与FROST不同，对其功能知之甚少。SPRAY定位于细胞器膜，可能通过钙调神经磷酸酶促进Ca 2+的分布，因为缺乏sp的突变体对FK 506敏感（Bok等人，2001）。在丝状真菌中，生长期间的形态变化需要重塑细胞壁多糖网络（Bowman和Free 2006; Latge 2007; Kamei等人2013）。真菌细胞壁主要由葡聚糖、几丁质、甘露聚糖和糖蛋白组成。许多细胞壁蛋白被GPI锚修饰，以允许堆叠到质膜外部。GPI锚在脂质部分上进行修饰...
Calcium ions (Ca2þ) are required for hyphal growth and development in filamentous fungi. During tip growth in mycelial extension, the model filamentous fungus Neurospora crassa relies upon an internally generated Ca2þ gradient to maintain polar growth, indicating that the filamentous morphology is controlled by intracellular Ca2þ gradients and calcium signaling factors (Jackson and Heath 1993; Levina et al. 1995; Prokisch et al. 1997; Alcantara-Sanchez et al. 2004; Bowman et al. 2011; Riquelme et al. 2011). Calcium signaling factors, such as calcium/calmodulin-dependent kinases that respond to changes in cytosolic free Ca2þ concentration, have been identified in N. crassa (Tamuli et al. 2013; Kumar and Tamuli 2014). Acute Ca2þ gradients in mycelial tips are created by a stretchactivated phospholipase C, which produces inositol trisphosphates that activate an ion channel to release Ca2þ at the tip (Silverman-Gavrila and Lew 2001, 2003). Deletion mutants of phospholipase C1 in N. crassa (plc-1 and splA2) show growth defects in response to an increase in Ca2þ concentration induced by a Ca2þ ionophore A23187 (Barman and Tamuli 2015). Additionally, several studies have suggested that Ca2þ-mediated signaling also regulates fungal thigmotropism, ie, hyphal growth response to mechanical stimuli. This phenomenon has been widely observed in fungi such as Candida albicans (Brand and Gow 2009; Brand et al. 2009), Aspergillus niger (Fischer et al. 2008), Magnaporthe grisea (Tucker and Talbot 2001), and N. crassa (Bowman et al. 2011, 2012). Both frost (fr) and spray (sp) single mutants of N. crassa have been reported to show significantly lower growth rates and hyperbranched mycelial phenotypes that can be restored by exogenous Ca2þ (Dicker and Turian 1990; Sone and Griffiths 1999; Bok et al. 2001). fr is an ortholog of the S. cerevisiae CDC1 gene, which encodes the essential lipid phosphatase Cdc1 that participates in calcium signaling by regulating cytosolic Mn2þ levels in the endoplasmic reticulum (Rossanese et al. 2001; Losev et al. 2008). CDC1 mutants are temperature-sensitive and have elevated intracellular Ca2þ levels at the restrictive temperature (Loukin and Kung 1995; Paidhungat and Garrett 1998a, b; Losev et al. 2008). Such CDC1-related phenotypes are suppressed by deletion of PER1 (Losev et al. 2008). Saccharomyces cerevisiae Per1 functions as a phospholipase A2-like protein, which is required for the glycosylphosphatidylinositol (GPI) remodeling pathway. The absence of Per1 may impair the association of GPI-anchored proteins to the membrane and alters phosphatidylinositol moieties in GPI anchors in yeast (Fujita et al. 2006). The N. crassa fr mutant has higher sensitivities to both Mn2þ and the calcineurin inhibitor FK506 (Sone and Griffiths 1999), indicating that FROST contributes to Mn2þ homeostasis and calcium signaling. Another N. crassa gene, sp, is a filamentous fungus-specific gene that encodes SPRAY, a putative calcium ion channel protein; unlike FROST, however, little is known about its function. SPRAY localizes in organelle membranes and likely contributes to the distribution of Ca2þ via calcineurin, as the mutant lacking sp is sensitive to FK506 (Bok et al. 2001). In filamentous fungi, morphological changes during growth require remodeling of the cell wall polysaccharide network (Bowman and Free 2006; Latge 2007; Kamei et al. 2013). The fungal cell wall is primarily composed of glucans, chitin, mannans, and glycoproteins. A number of cell wall proteins are modified by GPI anchors to allow stacking to plasma membrane exteriors. GPI anchors undergo modification on lipid moieties …