Dataset Information

Identification of a novel Rac1-interacting protein involved in membrane ruffling.

ABSTRACT: The Rac GTP binding proteins are implicated in actin cytoskeleton-membrane interaction in mammalian cells. In fibroblast cells, Rac has been shown to mediate growth factor-induced polymerization of actin to form membrane ruffles and lamellipodia. We report here the isolation of a noval Rac1-interacting protein, POR1. POR1 binds directly to Rac1, and the interaction of POR1 with Rac1 is GTP dependent. A mutation in the Rac1 effector binding loop shown to abolish membrane ruffling also abolishes interaction with POR1. Truncated versions of POR1 inhibit the induction of membrane ruffling by an activated mutant of Rac1, V12Rac1, in quiescent rat embryonic fibroblast REF52 cells. Furthermore, POR1 synergizes with an activated mutant of Ras, V12Ras, in the induction of membrane ruffling. These results suggest a potential role for POR1 in Rac1-mediated signaling pathways.

SUBMITTER: Van Aelst L

PROVIDER: S-EPMC452058 | biostudies-other | 1996 Aug

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Identification of a novel Rac1-interacting protein involved in membrane ruffling.

Van Aelst L L Joneson T T Bar-Sagi D D

The EMBO journal 19960801 15

The Rac GTP binding proteins are implicated in actin cytoskeleton-membrane interaction in mammalian cells. In fibroblast cells, Rac has been shown to mediate growth factor-induced polymerization of actin to form membrane ruffles and lamellipodia. We report here the isolation of a noval Rac1-interacting protein, POR1. POR1 binds directly to Rac1, and the interaction of POR1 with Rac1 is GTP dependent. A mutation in the Rac1 effector binding loop shown to abolish membrane ruffling also abolishes i ...[more]

PMID: 8670882

Similar Datasets

Project description:BACKGROUND:Bovine viral diarrhea virus (BVDV) belongs to the Flaviviridae family and the pestivius virus group. BVDV is responsible for significant economic loss in cattle industry worldwide because of reducing reproductive performance, increasing incidence of other diseases and mortality among young stock. The core (C) protein of the Flaviviridae family member is involved in host antiviral immune response through activation of related signaling pathways that affect the viral replication. However, the influence of C protein-interaction partners in BVDV infections is poorly defined. METHODS:To explore C-protein-interacting partners, yeast two-hybrid was used to screen the interaction protein of C protein using bovine peripheral blood mononuclear cell (PBMC) cDNA library. The co-immunoprecipitation and confocal assays were manipulated to determine the interaction between potential partners and C protein. Knockdown and overexpression of the partner were used to examine whether the C-protein-interacting partner plays a role in BVDV proliferation and virulence. Meanwhile, qRT-PCR and western blot assays were used to investigate the effect of C protein and C-protein-interacting partner on the immune response of host cells. RESULTS:We identified protein inhibitor of activated STAT 4 (PIAS4) as a novel interacting partner of the BVDV C protein. Co-immunoprecipitation and confocal assays demonstrated a strong interaction between C protein and PIAS4. Silencing of PIAS4 with small interfering RNA suppressed C protein expression and BVDV growth, while overexpression of PISA4 increased C protein expression and BVDV growth. The overexpression of PIAS4 increased the cell apoptosis. Meanwhile, the expressions of STAT4, SOCS3, IFITM, IFN-? were negatively regulated by the expression of PIAS4. The expression of C protein suppressed the antiviral proteins expression, and the inhibition effect was enhanced by interaction of PIAS4 and C protein. These results highlighted the beneficial properties of cellular PIAS4 for BVDV protein expression and growth. CONCLUSIONS:This study provides reliable clues for understanding the roles of PIAS4 in the regulation of BVDV growth.

Dataset Information

Identification of a novel Rac1-interacting protein involved in membrane ruffling.

Publications

Identification of a novel Rac1-interacting protein involved in membrane ruffling.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets