Shigunov Patrícia, Sotelo-Silveira Jose, Stimamiglio Marco Augusto, Kuligovski Crisciele, Irigoín Florencia, Badano Jose L, Munroe David, Correa Alejandro, Dallagiovanna Bruno
Stem Cells Basic Biology Laboratory, Instituto Carlos Chagas, FIOCRUZ, Algacyr Munhoz Mader 3775, Curitiba 81350-010, Brazil.
BMC Mol Biol. 2014 Jul 3;15:12. doi: 10.1186/1471-2199-15-12.
DZIP1 (DAZ-interacting protein 1) has been described as a component of the Hh signaling pathway with a putative regulatory role in ciliogenesis. DZIP1 interacts with DAZ RNA binding proteins in embryonic stem cells and human germ cells suggesting a role in mRNA regulation.
We investigated DZIP1 function in HeLa cells and its involvement in ribonucleoprotein complexes. DZIP1 was predominantly located in granules in the cytoplasm. Under oxidative stress conditions, DZIP1 re-localized to stress granules. DZIP appears to be important for the formation of stress granules during the stress response. We used immunoprecipitation assays with antibodies against DZIP1 and microarray hybridization to identify mRNAs associated with DZIP1. The genetic networks formed by the DZIP1-associated mRNAs were involved in cell cycle and gene expression regulation. DZIP1 is involved in the Hedgehog signaling pathway. We used cyclopamine, a specific inhibitor of this pathway, to analyze the expression of DZIP1 and its associated mRNAs. The abundance of DZIP1-associated mRNAs increased with treatment; however, the silencing or overexpression of DZIP1 in HeLa cells had no effect on the accumulation of the associated mRNAs. Polysomal profile analysis by sucrose gradient centrifugation demonstrated the presence of DZIP1 in the polysomal fraction.
Our results suggest that DZIP1 is part of an RNP complex that occupies various subcellular locations. The diversity of the mRNAs associated with DZIP1 suggests that this protein is a component of different RNPs associated with translating polysomes and with RNA granules.
DZIP1（DAZ相互作用蛋白1）已被描述为Hh信号通路的一个组成部分，在纤毛发生中具有假定的调节作用。DZIP1在胚胎干细胞和人类生殖细胞中与DAZ RNA结合蛋白相互作用，提示其在mRNA调节中发挥作用。
我们研究了DZIP1在HeLa细胞中的功能及其在核糖核蛋白复合物中的作用。DZIP1主要位于细胞质中的颗粒中。在氧化应激条件下，DZIP1重新定位于应激颗粒。DZIP似乎在应激反应期间应激颗粒的形成中起重要作用。我们使用针对DZIP1的抗体进行免疫沉淀测定和微阵列杂交，以鉴定与DZIP1相关的mRNA。由DZIP1相关mRNA形成的基因网络参与细胞周期和基因表达调节。DZIP1参与Hedgehog信号通路。我们使用环杷明（该通路的一种特异性抑制剂）来分析DZIP1及其相关mRNA的表达。随着处理，DZIP1相关mRNA的丰度增加；然而，在HeLa细胞中沉默或过表达DZIP1对相关mRNA的积累没有影响。通过蔗糖梯度离心进行的多核糖体谱分析表明DZIP1存在于多核糖体部分。
我们的结果表明，DZIP1是一个核糖核蛋白复合物的一部分，该复合物占据各种亚细胞位置。与DZIP1相关的mRNA的多样性表明，这种蛋白质是与翻译多核糖体和RNA颗粒相关的不同核糖核蛋白的一个组成部分。
