Journal article
Targeting Lyn tyrosine kinase through protein fusions encompassing motifs of Cbp (Csk-binding protein) and the SOCS box of SOCS1
Biochemical Journal, Vol.442(3), pp.611-620
2012
Abstract
The tyrosine kinase Lyn is involved in oncogenic signalling in several leukaemias and solid tumours, and we have previously identified a pathway centred on Cbp [Csk (C-terminal Src kinase)-binding protein] that mediates both enzymatic inactivation, as well as proteasomal degradation ofLyn via phosphorylation-dependent recruitment of Csk (responsible for phosphorylating the inhibitory C-terminal tyrosine of Lyn) and SOCS1 (suppressor of cytokine signalling 1; an E3 ubiquitin ligase). In the present study we show that fusing specific functional motifs of Cbp and domains of SOCS1 together generates a novel molecule capable of directing the proteasomal degradation of Lyn. We have characterized the binding of pY (phospho-tyrosine) motifs of Cbp to SFK (Src-family kinase) SH2 (Src homology 2) domains, identifying those with high affinity and specificity for the SH2 domain of Lyn and that are preferred substrates of active Lyn. We then fused them to the SB (SOCS box) of SOCS1 to facilitate interaction with the ubiquitination-promoting elongin B/C complex. As an eGFP (enhanced green fluorescent protein) fusion, these proteins can direct the polyubiquitination and proteasomal degradation of active Lyn. Expressing this fusion protein in DU145 cancer cells (but not LNCaP or MCF-7 cells), that require Lyn signalling for survival, promotes loss of Lyn, loss of caspase 3, appearance of an apoptotic morphology and failure to survive/expand. These findings show how functional domains of Cbp and SOCS1 can be fused together to generate molecules capable of inhibiting the growth of cancer cells that express high levels of active Lyn.
Details
- Title
- Targeting Lyn tyrosine kinase through protein fusions encompassing motifs of Cbp (Csk-binding protein) and the SOCS box of SOCS1
- Authors/Creators
- R.J. Whiting (Author/Creator) - The University of Western AustraliaC.J. Payne (Author/Creator) - Royal Perth HospitalJ. Satiaputra (Author/Creator) - The University of Western AustraliaN. Kucera (Author/Creator) - The University of Western AustraliaT.W. Qiu (Author/Creator) - The University of MelbourneS. Irtegun (Author/Creator) - The University of MelbourneN.J. Gunn (Author/Creator) - The University of MelbourneN.S. Lavova-Azmanova (Author/Creator) - The University of Western AustraliaT.D. Mulhern (Author/Creator) - The University of MelbourneE. Ingley (Author/Creator) - The University of Western Australia
- Publication Details
- Biochemical Journal, Vol.442(3), pp.611-620
- Publisher
- Portland Press, Ltd.
- Identifiers
- 991005540211807891
- Copyright
- © The Authors
- Murdoch Affiliation
- Murdoch University
- Language
- English
- Resource Type
- Journal article
UN Sustainable Development Goals (SDGs)
This output has contributed to the advancement of the following goals:
Source: InCites
Metrics
22 Record Views
InCites Highlights
These are selected metrics from InCites Benchmarking & Analytics tool, related to this output
- Collaboration types
- Domestic collaboration
- Citation topics
- 1 Clinical & Life Sciences
- 1.25 Molecular & Cell Biology - Cancer, Autophagy & Apoptosis
- 1.25.1481 Phosphatases and Rasopathies
- Web Of Science research areas
- Biochemistry & Molecular Biology
- ESI research areas
- Biology & Biochemistry