GENE EXPRESSION DURING SPORULATION

总体目标是了解基因表达是如何被调控的。 在孢子形成过程中，了解基因表达如何与 孢子形成过程中的形态变化。两个相互连接的 将寻求实现这一目标的方法。第一个是 继续分析两个基因座，SPIIA和SPVA，它们与 孢子形成过程中的主要形态事件：隔膜形成， 被母细胞吞噬前孢子，并组装 前孢子周围的保护层。转录了SpoIIA基因座 首先是1.7kb的RNA；这个区域包括RNA聚合酶的基因 西格玛因素。建议对其转录调控进行分析， 确定所涉及的因素并确定其行动目标 将5‘区添加到转录记录中。1.7kb转录本之间的关系 将研究从形成到隔膜的形成。斯皮拉的轨迹是 后来从上游启动子转录成约2.9kb的物种 吞噬的时间；大的转录本编码了青霉素结合 可能参与皮质形成的蛋白质，一种保护性的 孢子原生质体周围的一层。建议调查 该青霉素结合蛋白的特性和功能。有建议说 分析2.9kb转录本的调控，并将其与 与其他后期表达的孢子形成基因座的表达不同。Spova 该基因只在被吞噬后的前孢子中表达。它是 建议测试孢子是否有必要进行这种划分 形成，并调查划分的决定因素。 第二种方法是识别对植物至关重要的基因。 生长，也在特定的产孢量控制下。这类基因 在孢子形成的研究中很大程度上被忽视。然而，在那里 都可能对孢子的形成有实质性的了解。我们会 鉴定和研究直接或间接受 斯皮拉。我们对关键基因特别感兴趣，这些基因可能 隔膜形成所需的，并将调查FTSA的可能作用 和FtsZ在产孢期。

The overall objective is to understand how gene expression is regulated during spore formation and to understand how gene expression relates to the morphological changes during spore formation. Two interconnected approaches will be pursued towards this objective. The first is to continue analysis of two loci, spoIIA and spoVA, that are associated with major morphological events during spore formation: septum formation, engulfment of the prespore by the mother cell, and assembly of the protective layers around the prespore. The spoIIA locus is transcribed first as a 1.7 kb RNA; this region includes the gene for an RNA polymerase sigma factor. It is proposed to analyze the control of its transcription, identifying the factors involved and defining their targets of action in the region 5' to the transcript. The relationship of 1.7 kb transcript formation to septum formation will be investigated. The spoIIA locus is later transcribed from an upstream promoter as a 2.9 kb species at about the time of engulfment; the large transcript encodes a penicillin-binding protein which could be involved in formation of the cortex, a protective layer surrounding the spore protoplast. It is proposed to investigate the identity and function of this penicillin-binding protein. It is proposed to analyze the regulation of the 2.9 kb transcript and to relate its expression to that of other late-expressed sporulation loci. The spoVA locus is expressed exclusively in the prespore after engulfment. It is proposed to test if this compartmentalization is necessary for spore formation, and to investigate the determinants of compartmentalization. The second approach is to identify genes that are essential for vegetative growth and are also under sporulation-specific control. This class of gene has largely been neglected in studies of spore formation. However, there are likely to be a substantial understanding of spore formation. We will identify and study essential genes controlled directly or indirectly by spoIIA. We are particularly interested in essential genes that might be required for septum formation, and will investigate possible roles of ftsA and ftsZ in sporulation.