Alberti Adriana, Lodi Tiziana, Ferrero Iliana, Donnini Claudia
Dipartimento di Genetica Antropologia Evoluzione, Università degli Studi di Parma, Parco Area delle Scienze 11A, 43100 Parma, Italy.
Yeast. 2003 Oct 15;20(13):1085-96. doi: 10.1002/yea.1025.
Imp2p (Yil154c) is a transcriptional activator involved in glucose derepression of the maltose, galactose and raffinose utilization pathways and in resistance to thermal, oxidative or osmotic stress. We analysed the role of Imp2 in the regulation of GAL genes. Imp2 was shown to have a positive effect on glucose derepression of Leloir pathway genes and their activator gene GAL4. The effect of Imp2 on galactose metabolism was shown to be partially dependent on Mig1p. The Mig1-independent role depends on Nrg1p. However, disruption of both MIG1 and NRG1 only partially relieves the glucose repression of GAL genes in the Deltaimp2 mutant, indicating that Imp2 must also have other function(s). Moreover, the interaction between IMP2 and GAL6/BLH1, a recently isolated gene involved in the regulation of GAL genes that shares with Imp2 the ability to protect cells from the glycopeptide bleomycin, was also analysed. The results suggest a major role of Imp2 in a GAL6-independent pathway.
Imp2p（Yil154c）是一种转录激活因子，参与麦芽糖、半乳糖和棉子糖利用途径的葡萄糖去阻遏作用，以及对热、氧化或渗透胁迫的抗性。我们分析了Imp2在GAL基因调控中的作用。结果表明，Imp2对Leloir途径基因及其激活基因GAL4的葡萄糖去阻遏具有正向作用。Imp2对半乳糖代谢的影响部分依赖于Mig1p。不依赖Mig1的作用则依赖于Nrg1p。然而，同时破坏MIG1和NRG1只能部分缓解Deltaimp2突变体中GAL基因的葡萄糖阻遏，这表明Imp2肯定还具有其他功能。此外，我们还分析了IMP2与GAL6/BLH1之间的相互作用，GAL6/BLH1是最近分离出的一个参与GAL基因调控的基因，它与Imp2一样具有保护细胞免受糖肽博来霉素影响的能力。结果表明Imp2在一条不依赖GAL6的途径中起主要作用。
