A novel Jun N‐terminal kinase (JNK)‐binding protein that enhances the activation of JNK by MEK kinase 1 and TGF‐β‐activated kinase 1

Abstract

We have identified a novel Jun N-terminal kinase (JNK)-binding protein, termed JNKBP1, and examined its binding affinity for JNK1, JNK2, JNK3, and extracellular signal-regulated kinase 2 (ERK2) in COS-7 cells. JNKBP1 preferentially interacted with the JNKs, but not with ERK2. Furthermore, we investigated the effect of overexpressing JNKBP1 on the JNK and ERK signaling pathways in COS-7 cells. JNKBP1 alone had only a marginal effect on JNK activity. However, the activation of JNK by MEK kinase 1 and TGF-L Lactivated kinase 1 was significantly enhanced in the presence of JNKBP1. In contrast, JNKBP1 had no or very little effect on the ERK signaling pathway. These results suggest that JNKBP1 functions to facilitate the specific and efficient activation of the JNK signaling pathways.z 1999 Federation of European Biochemical Societies.

The c-Jun N-terminal Kinase (JNK)-binding Protein (JNKBP1) Acts as a Negative Regulator of NOD2 Protein Signaling by Inhibiting Its Oligomerization Process

“…JNKBP1 was initially identified in mice as a protein interacting with JNK and playing a scaffold role in the JNK-dependent pathway (16). This function is independent on N-terminal WD-40 domain but involves a region in the C-terminal part (Fig.…”

“…Expression of JNKBP1 in Human Cell Lines and in the Intestine-Little is known about the tissue distribution of JNKBP1 in humans, whereas it has been shown to be ubiquitously expressed in mouse tissues and principally in the brain (16). To assess the expression of human JNKBP1 in various kinds of cells, we determined the levels of JNKBP1 mRNA in different human cell lines by qRT-PCR.…”

“…Mouse JNKBP1, also named mitogen-activated protein kinase-binding protein 1 (MAPKBP1), was initially identified in a yeast two-hybrid system used to search for proteins interacting with JNK3 (16). JNKBP1 contains 12 WD-40 repeats in the N-terminal part and a JNK-binding region located in the C-terminal region (16).…”

“…JNKBP1 contains 12 WD-40 repeats in the N-terminal part and a JNK-binding region located in the C-terminal region (16). JNKBP1 appears to be ubiquitously expressed in mouse tissues and to play a scaffold function in JNK signaling.…”

Xenopus Death Receptor-M1 and -M2, New Members of the Tumor Necrosis Factor Receptor Superfamily, Trigger Apoptotic Signaling by Differential Mechanisms

“…The pcDNA3 His-S-JNK2 expression vector was described previously (39). The ORF of Xenopus caspase-8 was amplified from Xenopus liver cDNA by PCR using two primers, 5Ј-AGTGACCTGTTAAGTTCTA-CAGT-3Ј and 5Ј-TTACATGGCATTAGGAGGTGG-3Ј.…”