Instituto de Biomedicina de Valencia, CSIC and CIBER de Enfermedades Raras (CIBERER), Jaime Roig 11, 46010 Valencia, Spain.
Int J Biochem Cell Biol. 2009 Dec;41(12):2431-9. doi: 10.1016/j.biocel.2009.07.002. Epub 2009 Jul 16.
Mammalian AMP-activated protein kinase (AMPK) is a heterotrimeric serine/threonine protein kinase that acts as a sensor of cellular energy status. It interacts with a great variety of different substrates leading to short-term (i.e. regulation of the activity of different enzymes by direct phosphorylation) and long-term effects (i.e. regulation of transcriptional activity of different transcription factors). In this work, we describe the use of the yeast two-hybrid technology to identify additional proteins that interact with the different subunits of AMPK. We have performed three yeast two-hybrid screenings of a human skeletal muscle cDNA library using three different baits: a constitutively active form of AMPKalpha2 (LexA-AMPKalpha2-T172D) co-expressed with AMPKgamma1, LexA-AMPKbeta2 and LexA-AMPKgamma3. Our results identify novel interaction partners of AMPK in human skeletal muscle. We also further characterize the interaction of AMPK with one of these novel interacting proteins, the non-ATPase subunit of the proteasome PSMD11. Our results indicate that AMPK is able to interact physically with this subunit and modify its phosphorylation status, supporting a possible role for AMPK in regulating proteasome function.
哺乳动物的 AMP 激活蛋白激酶（AMPK）是一种异三聚体丝氨酸/苏氨酸蛋白激酶，作为细胞能量状态的传感器。它与各种不同的底物相互作用，导致短期（即通过直接磷酸化调节不同酶的活性）和长期效应（即调节不同转录因子的转录活性）。在这项工作中，我们描述了使用酵母双杂交技术来鉴定与 AMPK 的不同亚基相互作用的其他蛋白质。我们使用三种不同的诱饵：与 AMPKγ1、LexA-AMPKβ2 和 LexA-AMPKγ3 共表达的 AMPKα2 的组成性激活形式（LexA-AMPKα2-T172D），对人骨骼肌 cDNA 文库进行了三次酵母双杂交筛选。我们的结果确定了人骨骼肌中 AMPK 的新的相互作用伙伴。我们还进一步表征了 AMPK 与其中一种新的相互作用蛋白，蛋白酶体 PSMD11 的非 ATP 酶亚基的相互作用。我们的结果表明，AMPK 能够与该亚基物理相互作用并修饰其磷酸化状态，支持 AMPK 在调节蛋白酶体功能中的可能作用。
