Receptor-mediated endoproteolytic activation of two transcription factors in yeast
Receptor-mediated endoproteolytic activation of two transcription factors in yeast
复制标题
DOI：
10.1101/gad.239202
复制
发表时间：
2002-12-15
影响因子：
10.5
通讯作者：
Ljungdahl, PO
中科院分区：
文献类型：
--
作者：
Andréasson, C;Ljungdahl, PO
酵母菌具有质膜外氨基酸传感器，作为配体激活受体。这种多聚体传感器，被称为SPS传感器，启动信号，调节适当的氨基酸摄取所需的基因表达。Stp1p和Stp2p是结合到sps传感器调节基因启动子内特定序列的转录因子。这些因子在激活转录方面表现出冗余和重叠的能力。我们发现Stp1p和Stp2p作为潜在的细胞质前体被合成，SPS传感器响应胞外氨基酸诱导Stp1p和Stp2p的快速内蛋白水解加工。Stp1p/Stp2p的加工独立于蛋白酶体的功能，没有其他成分的明显参与。这些转录因子的较短形式，缺乏n端抑制结构域，靶向细胞核，在那里它们反激活sps传感器靶基因。这些结果定义了一个完全独特和简化的代谢控制途径，直接将质膜上启动的环境信号传递到酵母细胞核的转录激活。
Yeast possess a plasma membrane sensor of external amino acids that functions as a ligand-activated receptor. This multimeric sensor, dubbed the SPS sensor, initiates signals that regulate the expression of genes required for proper amino acid uptake. Stp1p and Stp2p are transcription factors that bind to specific sequences within the promoters of SPS-sensor-regulated genes. These factors exhibit redundant and overlapping abilities to activate transcription. We have found that Stp1p and Stp2p are synthesized as latent cytoplasmic precursors, In response to extracellular amino acids, the SPS sensor induces the rapid endoproteolytic processing of Stp1p and Stp2p. The processing of Stp1p/Stp2p occurs independently of proteasome function and without the apparent involvement of additional components. The shorter forms of these transcription factors, lacking N-terminal inhibitory domains, are targeted to the nucleus, where they transactivate SPS-sensor target genes, These results define a completely unique and streamline metabolic control pathway that directly routes environmental signals initiated at the plasma membrane to transcriptional activation in the nucleus of yeast.