Fungal Cell Biology Group, Institute of Cell Biology, The University of Edinburgh, Edinburgh, United Kingdom.
PLoS One. 2012;7(8):e42565. doi: 10.1371/journal.pone.0042565. Epub 2012 Aug 10.
In order to produce multicellular structures filamentous fungi combine various morphogenetic programs that are fundamentally different from those used by plants and animals. The perithecium, the female sexual fruitbody of Neurospora crassa, differentiates from the vegetative mycelium in distinct morphological stages, and represents one of the more complex multicellular structures produced by fungi. In this study we defined the stages of protoperithecial morphogenesis in the N. crassa wild type in greater detail than has previously been described; compared protoperithecial morphogenesis in gene-deletion mutants of all nine mitogen-activated protein (MAP) kinases conserved in N. crassa; confirmed that all three MAP kinase cascades are required for sexual development; and showed that the three different cascades each have distinctly different functions during this process. However, only MAP kinases equivalent to the budding yeast pheromone response and cell wall integrity pathways, but not the osmoregulatory pathway, were essential for vegetative cell fusion. Evidence was obtained for MAP kinase signaling cascades performing roles in extracellular matrix deposition, hyphal adhesion, and envelopment during the construction of fertilizable protoperithecia.
为了生成多细胞结构，丝状真菌结合了各种形态发生程序，这些程序与动植物使用的程序从根本上不同。新拟青霉的子囊果，是其雌性有性生殖体，在不同的形态发生阶段从营养菌丝体分化而来，代表了真菌产生的更复杂的多细胞结构之一。在这项研究中，我们比以前更详细地定义了新拟青霉野生型原囊果形态发生的阶段；比较了在新拟青霉中保守的 9 种有丝分裂原激活蛋白激酶（MAPK）基因缺失突变体中原囊果形态发生；证实了所有三种 MAP 激酶级联反应都需要有性发育；并表明在这个过程中，这三个不同的级联反应各自具有明显不同的功能。然而，只有与出芽酵母交配型反应和细胞壁完整性途径相当的 MAP 激酶，而不是渗透压调节途径，对营养细胞融合是必需的。有证据表明，MAP 激酶信号级联在构建可育原囊果的细胞外基质沉积、菌丝附着和包裹过程中发挥作用。
