βPIX controls cell motility and neurite extension by regulating the distribution of GIT1
βPIX controls cell motility and neurite extension by regulating the distribution of GIT1
Cell motility entails the reorganization of the cytoskeleton and membrane trafficking for effective protrusion. GIT1/p95-APP1 is a member of a family of GTPase-activating proteins for ARF GTPases that affect endocytosis, adhesion and migration. GIT1 associates with paxillin and a complex including the Rac/Cdc42 exchanging factors PIX/Cool and the kinase PAK. In this study, we show that overexpression of βPIX induces the accumulation of endogenous and overexpressed GIT1 at large structures similar to those induced by an ArfGAP-defective mutant of GIT1 (p95-C2). Immunohistochemical analysis and immunoelectron microscopy reveal that these structures include the endogenous transferrin receptor. Time-lapse analysis during motogenic stimuli shows that the formation and perinuclear accumulation of the p95-C2-positive structures is paralleled by inhibition of lamellipodium formation and cell retraction. Both dimerization and a functional SH3 domain of βPIX are required for the accumulation of GIT1 in fibroblasts, which is prevented by the monomeric PIX-PG-ΔLZ. This mutant also prevents the formation of endocytic aggregates and inhibition of neurite outgrowth in retinal neurons expressing p95-C2. Our results indicate that βPIX is an important regulator of the subcellular distribution of GIT1, and suggest that alteration in the level of expression of the complex affects the endocytic compartment and cell motility.
- Goa University India
- University of Genoa Italy
- Vita-Salute San Raffaele University Italy
GTPase-Activating Proteins, Cell Cycle Proteins, Chick Embryo, Protein Serine-Threonine Kinases, Transfection, Protein Structure, Tertiary, p21-Activated Kinases, Cell Movement, COS Cells, Chlorocebus aethiops, Neurites, Animals, Guanine Nucleotide Exchange Factors, Mutant Proteins, Tissue Distribution, Cells, Cultured, Rho Guanine Nucleotide Exchange Factors
GTPase-Activating Proteins, Cell Cycle Proteins, Chick Embryo, Protein Serine-Threonine Kinases, Transfection, Protein Structure, Tertiary, p21-Activated Kinases, Cell Movement, COS Cells, Chlorocebus aethiops, Neurites, Animals, Guanine Nucleotide Exchange Factors, Mutant Proteins, Tissue Distribution, Cells, Cultured, Rho Guanine Nucleotide Exchange Factors
3 Research products, page 1 of 1
- 2017IsRelatedTo
- 2017IsRelatedTo
- 2017IsRelatedTo
citations This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).43 popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.Top 10% influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).Top 10% impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.Top 10%
