GENE EXPRESSION DURING SPORULATION

总的目标是了解基因表达是如何调节的 在孢子形成过程中，并了解基因表达如何与 孢子形成过程中的形态变化。 两个互连 将为实现这一目标采取各种办法。 一是 继续分析两个位点，spoIIA和spoVA，这与 孢子形成过程中的主要形态学事件：隔膜形成， 前孢子被母细胞吞噬， 前孢子周围的保护层。 SpoIIA基因座转录 首先是1.7 kb RNA;该区域包括RNA聚合酶基因 西格玛因子 建议分析其转录的控制， 确定所涉因素并确定其行动目标， 转录本的5 ′区。 1.7kb转录本之间的关系 将研究隔膜形成。 SpoIIA基因座是 后来从上游启动子转录为2.9 kb的种类，约 吞噬的时间;大转录本编码青霉素结合 这种蛋白质可能参与皮层的形成， 孢子原生质体周围的一层。 建议调查 这种青霉素结合蛋白的身份和功能。 拟 分析2.9kb转录本的调控，并将其与 与其他晚期表达的孢子形成位点的表达一致。 关于SpoVA 位点仅在被吞噬后的前孢子中表达。 是 建议测试这种区室化对于孢子是否必要 形成，并调查区室化的决定因素。 第二种方法是鉴定植物生长所必需的基因， 生长，也受到孢子化特异性控制。 这类基因 在孢子形成的研究中很大程度上被忽视了。 但 很可能是对孢子形成的实质性理解。 我们将 识别和研究直接或间接控制的必需基因， 战利品。 我们特别感兴趣的是那些 需要的隔膜形成，并将调查可能的作用ftsA 和ftsZ在孢子形成中的作用。

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.