Sato T, Lopez M C, Sugioka S, Jigami Y, Baker H V, Uemura H
Department of Molecular Biology, National Institute of Bioscience and Human-Technology, Tsukuba Research Center (MITI), Higashi 1-1, Tsukuba, Ibaraki, Japan.
FEBS Lett. 1999 Dec 17;463(3):307-11. doi: 10.1016/s0014-5793(99)01654-3.
Glycolytic gene expression is mediated by the Gcr1p-Gcr2p transcriptional activation complex. A screen for multicopy suppressors of gcr2 yielded SGC1. SGC1's suppression activity was specific to gcr2, it did not extend to gcr1. Disruption of SGC1 moderately affected glycolytic enzyme activities, although no growth defect was evident. Sgc1p exhibits a bHLH motif which is characteristic of E-box DNA-binding proteins. DNA footprinting experiments demonstrated Sgc1p's ability to bind at an E-box. However, its binding specificity was less than 10-fold, which is also characteristic of E-box binding proteins. LexA fusion experiments demonstrated that Sgc1p has weak intrinsic activating activity independent of GCR1 and GCR2. We propose that Sgc1p binds at E-boxes of glycolytic genes and contributes to their activation.
糖酵解基因表达由Gcr1p - Gcr2p转录激活复合物介导。对gcr2多拷贝抑制子的筛选得到了SGC1。SGC1的抑制活性对gcr2具有特异性，并不扩展到gcr1。SGC1的破坏适度影响糖酵解酶活性，尽管没有明显的生长缺陷。Sgc1p表现出一个bHLH基序，这是E - 盒DNA结合蛋白的特征。DNA足迹实验证明Sgc1p能够在一个E - 盒处结合。然而，其结合特异性小于10倍，这也是E - 盒结合蛋白的特征。LexA融合实验表明Sgc1p具有独立于GCR1和GCR2的弱内在激活活性。我们提出Sgc1p结合在糖酵解基因的E - 盒处并有助于它们的激活。
