Published online before print April 13, 2007

This Article Full Text Full Text (PDF) Supplemental Material All Versions of this Article: ajpath.2007.061266v1 170/6/2042    most recent Purchase Article View Shopping Cart Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Han, J. M. Articles by Kim, S. Search for Related Content PubMed Articles by Han, J. M. Articles by Kim, S.

(American Journal of Pathology. 2007;170:2042-2054.)
© 2007 American Society for Investigative Pathology
DOI: 10.2353/ajpath.2007.061266

Aminoacyl-tRNA Synthetase-Interacting Multifunctional Protein 1/p43 Controls Endoplasmic Reticulum Retention of Heat Shock Protein gp96

Its Pathological Implications in Lupus-Like Autoimmune Diseases

Jung Min Han^*, Sang Gyu Park, Bei Liu, Bum-Joon Park, Jin Young Kim, Cheng He Jin, Yeong Wook Song, Zihai Li and Sunghoon Kim

From Imagene Company Biotechnology Incubating Center,^* Golden Helix, the National Creative Research Initiatives Center for Aminoacyl-tRNA Synthetase Network, College of Pharmacy, and the Department of Internal Medicine, National Research Laboratory for Rheumatic Diseases, College of Medicine, Seoul National University, Seoul, Korea; and the Center for Immunotherapy of Cancer and Infectious Diseases, University of Connecticut School of Medicine, Farmington, Connecticut

Aminoacyl-tRNA synthetase-interacting multifunctional protein 1 (AIMP1; previously known as p43) is a multifunctional protein that was initially found in multitRNA synthetase complex. In the present study, screening of the AIMP1-binding proteins revealed that AIMP1 can form a molecular complex with heat shock protein gp96. AIMP1 enhances gp96 dimerization and the interaction between gp96 and KDEL receptor-1 (KDELR-1), which mediates the retrieval of KDEL-containing proteins from Golgi to the endoplasmic reticulum (ER). The interaction between gp96 and KDELR-1 was reduced in AIMP1-deficient cells, and this disturbed ER retention of gp96 and increased its cell surface localization. Moreover, this localization of gp96 at the cell surface was suppressed by its interaction with AIMP1 and enhanced by the depletion of endogenous AIMP1. In addition, AIMP1-deficient mice showed dendritic cell activation attributable to increased gp96 surface presentation and lupus-like autoimmune phenotypes. These results suggest that AIMP1 acts as a regulator of the ER retention of gp96 and provide a new perspective of the regulatory mechanism underlying immune stimulation by gp96.

This article has been cited by other articles:

				M. Kapoor, Q. Zhou, F. Otero, C. A. Myers, A. Bates, R. Belani, J. Liu, J.-K. Luo, E. Tzima, D.-E. Zhang, et al. Evidence for Annexin II-S100A10 Complex and Plasmin in Mobilization of Cytokine Activity of Human TrpRS J. Biol. Chem., January 25, 2008; 283(4): 2070 - 2077. [Abstract] [Full Text] [PDF]