Activator protein-1 (AP1) regulates the promoter activity of a large number of genes associated with developmental, proliferative, inflammatory, and homeostatic processes in human connective tissue cells. Some of these genes (e.g., cyclooxygenase-2) are regulated by the protein kinase C (PKC) inhibi
Phosphorylation-dependent dimerization and subcellular localization of islet-brain 1/c-Jun N-terminal kinase-interacting protein 1
✍ Scribed by T. Borsello; C. Centeno; I.M. Riederer; J.-A. Haefliger; B.M. Riederer
- Publisher
- John Wiley and Sons
- Year
- 2007
- Tongue
- English
- Weight
- 762 KB
- Volume
- 85
- Category
- Article
- ISSN
- 0360-4012
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
Islet‐brain 1 [IB1; also termed c‐Jun N‐terminal kinase (JNK)‐interacting protein 1 (JIP‐1] is involved in the apoptotic signaling cascade of JNK and functions as a scaffold protein. It organizes several MAP kinases and the microtubule‐transport motor protein kinesin and relates to other signal‐transducing molecules such as the amyloid precursor protein. Here we have identified IB1/JIP‐1 using different antibodies that reacted with either a monomeric or a dimeric form of IB1/JIP‐1. By immunoelectron microscopy, differences in the subcellular localization were observed. The monomeric form was found in the cytoplasmic compartment and is associated with the cytoskeleton and with membranes, whereas the dimeric form was found in addition in nuclei. After treatment of mouse brain homogenates with alkaline phosphatase, the dimeric form disappeared and the monomeric form decreased its molecular weight, suggesting that an IB1/JIP‐1 dimerization is phosphorylation dependent and that IB1 exists in several phospho‐ forms. N‐methyl‐D‐aspartate receptor activation induced a dephosphorylation of IB1/JIP‐1 in primary cultures of cortical neurons and reduced homodimerization. In conclusion, these data suggest that IB1/JIP‐1 monomers and dimers may differ in compartmental localization and thus function as a scaffold protein of the JNK signaling cascade in the cytoplasm or as a transcription factor in nuclei. © 2007 Wiley‐Liss, Inc.
📜 SIMILAR VOLUMES
## Abstract Ependymin (EPN) is a goldfish brain neurotrophic factor previously shown to function in a variety of cellular events related to long‐term memory formation and neuronal regeneration. CMX‐8933, an 8‐amino‐acid synthetic peptide fragment of EPN, was designed for aiding an investigation of
## Abstract Nitric oxide (NO) can regulate chondrocyte activities. This study was aimed to evaluate the molecular mechanisms of NO donor sodium nitroprusside (SNP)‐induced insults to human chondrocytes. Exposure of human chondrocytes to SNP increased cellular NO levels but decreased cell viability
## Abstract The roles of the mitogen‐activated kinase protein (MAPK) pathway, nuclear factor‐kappa B (NF‐κB), and activator protein‐1 (AP‐1) in cellular responses to growth factors and mitogen are well established. However, the manner by which these proliferative pathways are affected by the tumor
The protozoan parasite Leishmania fails to activate naive macrophages for proinflammatory cytokines production, and selectively impairs signal transduction pathways in infected macrophages. Because mitogen-activated protein kinases (MAPK)-and NF-‹ B-dependent signaling pathways regulate proinflammat