Transcription Signals and High-ordered Regulatory Mechanisms for Plant Gene Expression

本合作研究（A）的目的是通过顺式作用DNA序列与反式调控因子之间的相互作用来研究植物基因表达的调控机制。每个参与者使用自己的实验系统，并鉴定了基因特异性调节DNA序列和序列特异性DNA结合蛋白。确定小麦H3基因S期特异性表达的顺式元件是近端启动子区的六聚体和八聚体基序，以及六聚体特异性DNA结合蛋白HBP-1a（17），通过cDNA克隆的序列分析，表明其为bZIP型蛋白。刀豆（Canavalina gladiata）伴刀豆球蛋白A（concanavalin A）基因的主要顺式区位于-745的下游，并鉴定了与该区域相互作用的DNA结合蛋白。鉴定了赋予甘薯α-淀粉酶和孢子素基因高水平表达诱导的DNA序列。DNA结合因子SP 8BF与α-淀粉酶基因5 ′上游的CGTCA基序结合。分离到一个生长素诱导的基因par基因，发现其顺式区为正或负，并鉴定了与Ri质粒中rolC基因顺式区结合的DNA结合蛋白。

The aim of the present cooperation research (A) was to investigate the regulatory mechanisms of plant gene expression though the interaction between cis-acting DNA sequences and trans-control factors. Each partaker used his own experimental system and has identified gene-specific regulatory DNA sequences and the sequence-specific DNA binding proteins.The cis-elements defining the S phase-specific expression of wheat H3 gene were indentified to be the hexameric and octameric motifs in the proximal promoter region and the hexamer-specific DNA-binding protein, HBP-1a(17), was shown to be a bZIP-type protein by sequence analysis of the cDNA clone. The major cis-regions of a concanavalin A gene of Canavalina gladiata was shown to be located downstream of -745 and some DNA-binding proteins that can interact with the regions were also identified. The DNA sequences conferring the induction of high-level of expression of a sweet potato alpha-amylase and sporamin genes was identified. The DNA-binding factor SP8BF was demonstratedto bind to a CGTCA motif in the 5'-upstream region of the alpha-amylase gene. One of the auxin-induced genes, par gene, was isolated and the positive or negative cis-regions were found. DNA-binding proteins that bind to the cis-regions of rolC gene in Ri plasmid were identified.