PDF(Pubmed)
Abstract：
Conchosporangia maturation is crucial for the yield of Pyropia/Porphyra. However, the molecular mechanisms underlying this process are poorly understood. In this study, we selected two strains of Pyropia haitanensis that show significant differences in conchosporangia maturation as materials to produce RNA-Seq libraries. Then, we identified key molecular pathways and genes involved in conchosporangia maturation by conducting a weighted gene co-expression network analysis. Two specific modules were identified, and included functions such as phosphorus metabolism, lipid metabolism, and the phosphatidylinositol signaling system. The hub genes that responded positively during conchosporangia maturation encoded diacylglycerol kinase (DGK) and phosphatidylinositol-3-phosphate-5-kinase, which are involved in the synthesis of phosphatidic acid, a key component of lipid metabolism. A full-length DGK sequence of P. haitanensis, designated as PhDGK1, was obtained by rapid-amplification of cDNA ends. Conserved motif and phylogenetic tree analyses showed that PhDGK1 belongs to DGK Cluster II. The transcript level of PhDGK1 increased during conchosporangia maturation in both strains, but increased earlier, and to higher levels, in the early-maturing strain than in the late-maturing strain. This pattern of gene expression was consistent with the patterns of maturity and changes in pigment contents. These results indicate that lipid metabolism plays a key role in regulating conchosporangia maturation in Pyropia spp., and that PhDGK1 might be a useful molecular marker for breeding new early-maturing strains.
摘要：
孢子孢子囊的成熟对于Pyropia/Porphyra的产量至关重要。然而,这个过程背后的分子机制知之甚少。在这项研究中,我们选择了两株在孢子囊成熟方面表现出显着差异的海山梨属菌株作为产生RNA-Seq文库的材料。然后，通过进行加权基因共表达网络分析,我们确定了与结孢菌成熟相关的关键分子途径和基因.确定了两个具体模块，包括磷代谢等功能，脂质代谢，和磷脂酰肌醇信号系统。在结孢菌成熟过程中反应积极的hub基因编码二酰甘油激酶（DGK）和磷脂酰肌醇-3-磷酸-5-激酶，参与磷脂酸的合成，脂质代谢的关键组成部分。海丹毕赤酵母的全长DGK序列，命名为PhDGK1,通过cDNA末端的快速扩增获得。保守的基序和系统发育树分析表明，PhDGK1属于DGK集群II。PhDGK1的转录水平在两个菌株的孢子囊成熟期间增加，但增加得更早，和更高的水平，早熟菌株比晚熟菌株。这种基因表达模式与成熟度和色素含量变化的模式一致。这些结果表明，脂质代谢在调节Pyropiaspp的孢子囊成熟中起关键作用。,PhDGK1可能是育种新的早熟菌株的有用分子标记。
