Tags

Type your tag names separated by a space and hit enter

Direct binding of PP2A to Sprouty2 and phosphorylation changes are a prerequisite for ERK inhibition downstream of fibroblast growth factor receptor stimulation.
J Biol Chem. 2007 Mar 23; 282(12):9117-26.JB

Abstract

In the context of fibroblast growth factor (FGF) signaling, Sprouty2 (Spry2) is the most profound inhibitor of the Ras/ERK pathway as compared with other Spry isoforms. An exclusive, necessary, but cryptic PXXPXR motif in the C terminus of Spry2 is revealed upon stimulation. The activation of Spry2 appears to be linked to sequences in the N-terminal half of the protein and correlated with a bandshifting seen on SDS-PAGE. The band-shifting is likely caused by changes in the phosphorylation status of key Ser and Thr residues following receptor stimulation. Dephosphorylation of at least two conserved Ser residues (Ser-112 and Ser-115) within a conserved Ser/Thr sequence is accomplished upon stimulation by a phosphatase that binds to Spry2 around residues 50-60. We show that human Spry2 co-immunoprecipitates with both the catalytic and the regulatory subunits of protein phosphatase 2A (PP2A-C and PP2A-A, respectively) in cells upon FGF receptor (FGFR) activation. PP2A-A binds directly to Spry2, but not to Spry2Delta50-60 (Delta50-60), and the activity of PP2A increases with both FGF treatment and FGFR1 overexpression. c-Cbl and PP2A-A compete for binding centered around Tyr-55 on Spry2. We show that there are at least two distinct pools of Spry2, one that binds PP2A and another that binds c-Cbl. c-Cbl binding likely targets Spry2 for ubiquitin-linked destruction, whereas the phosphatase binding and activity are necessary to dephosphorylate specific Ser/Thr residues. The resulting change in tertiary structure enables the Pro-rich motif to be revealed with subsequent binding of Grb2, a necessary step for Spry2 to act as a Ras/ERK pathway inhibitor in FGF signaling.

Authors+Show Affiliations

Institute of Molecular and Cell Biology, 61 Biopolis Drive, Proteos, Singapore 138673.No affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

17255109

Citation

Lao, Dieu-Hung, et al. "Direct Binding of PP2A to Sprouty2 and Phosphorylation Changes Are a Prerequisite for ERK Inhibition Downstream of Fibroblast Growth Factor Receptor Stimulation." The Journal of Biological Chemistry, vol. 282, no. 12, 2007, pp. 9117-26.
Lao DH, Yusoff P, Chandramouli S, et al. Direct binding of PP2A to Sprouty2 and phosphorylation changes are a prerequisite for ERK inhibition downstream of fibroblast growth factor receptor stimulation. J Biol Chem. 2007;282(12):9117-26.
Lao, D. H., Yusoff, P., Chandramouli, S., Philp, R. J., Fong, C. W., Jackson, R. A., Saw, T. Y., Yu, C. Y., & Guy, G. R. (2007). Direct binding of PP2A to Sprouty2 and phosphorylation changes are a prerequisite for ERK inhibition downstream of fibroblast growth factor receptor stimulation. The Journal of Biological Chemistry, 282(12), 9117-26.
Lao DH, et al. Direct Binding of PP2A to Sprouty2 and Phosphorylation Changes Are a Prerequisite for ERK Inhibition Downstream of Fibroblast Growth Factor Receptor Stimulation. J Biol Chem. 2007 Mar 23;282(12):9117-26. PubMed PMID: 17255109.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Direct binding of PP2A to Sprouty2 and phosphorylation changes are a prerequisite for ERK inhibition downstream of fibroblast growth factor receptor stimulation. AU - Lao,Dieu-Hung, AU - Yusoff,Permeen, AU - Chandramouli,Sumana, AU - Philp,Robin J, AU - Fong,Chee Wai, AU - Jackson,Rebecca A, AU - Saw,Tzuen Yih, AU - Yu,Chye Yun, AU - Guy,Graeme R, Y1 - 2007/01/25/ PY - 2007/1/27/pubmed PY - 2007/5/3/medline PY - 2007/1/27/entrez SP - 9117 EP - 26 JF - The Journal of biological chemistry JO - J. Biol. Chem. VL - 282 IS - 12 N2 - In the context of fibroblast growth factor (FGF) signaling, Sprouty2 (Spry2) is the most profound inhibitor of the Ras/ERK pathway as compared with other Spry isoforms. An exclusive, necessary, but cryptic PXXPXR motif in the C terminus of Spry2 is revealed upon stimulation. The activation of Spry2 appears to be linked to sequences in the N-terminal half of the protein and correlated with a bandshifting seen on SDS-PAGE. The band-shifting is likely caused by changes in the phosphorylation status of key Ser and Thr residues following receptor stimulation. Dephosphorylation of at least two conserved Ser residues (Ser-112 and Ser-115) within a conserved Ser/Thr sequence is accomplished upon stimulation by a phosphatase that binds to Spry2 around residues 50-60. We show that human Spry2 co-immunoprecipitates with both the catalytic and the regulatory subunits of protein phosphatase 2A (PP2A-C and PP2A-A, respectively) in cells upon FGF receptor (FGFR) activation. PP2A-A binds directly to Spry2, but not to Spry2Delta50-60 (Delta50-60), and the activity of PP2A increases with both FGF treatment and FGFR1 overexpression. c-Cbl and PP2A-A compete for binding centered around Tyr-55 on Spry2. We show that there are at least two distinct pools of Spry2, one that binds PP2A and another that binds c-Cbl. c-Cbl binding likely targets Spry2 for ubiquitin-linked destruction, whereas the phosphatase binding and activity are necessary to dephosphorylate specific Ser/Thr residues. The resulting change in tertiary structure enables the Pro-rich motif to be revealed with subsequent binding of Grb2, a necessary step for Spry2 to act as a Ras/ERK pathway inhibitor in FGF signaling. SN - 0021-9258 UR - https://www.unboundmedicine.com/medline/citation/17255109/Direct_binding_of_PP2A_to_Sprouty2_and_phosphorylation_changes_are_a_prerequisite_for_ERK_inhibition_downstream_of_fibroblast_growth_factor_receptor_stimulation_ L2 - http://www.jbc.org/cgi/pmidlookup?view=long&pmid=17255109 DB - PRIME DP - Unbound Medicine ER -