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Vukojević K, Šoljić V, Martinović V, Raguž F, Filipović N. The Ubiquitin-Associated and SH3 Domain-Containing Proteins (UBASH3) Family in Mammalian Development and Immune Response. Int J Mol Sci 2024; 25:1932. [PMID: 38339213 PMCID: PMC10855836 DOI: 10.3390/ijms25031932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 01/29/2024] [Accepted: 02/02/2024] [Indexed: 02/12/2024] Open
Abstract
UBASH3A and UBASH3B are protein families of atypical protein tyrosine phosphatases that function as regulators of various cellular processes during mammalian development. As UBASH3A has only mild phosphatase activity, its regulatory effects are based on the phosphatase-independent mechanisms. On the contrary, UBASH3B has strong phosphatase activity, and the suppression of its receptor signalling is mediated by Syk and Zap-70 kinases. The regulatory functions of UBASH3A and UBASH3B are particularly evident in the lymphoid tissues and kidney development. These tyrosine phosphatases are also known to play key roles in autoimmunity and neoplasms. However, their involvement in mammalian development and its regulatory functions are largely unknown and are discussed in this review.
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Affiliation(s)
- Katarina Vukojević
- Department of Anatomy, Histology and Embryology, University of Split School of Medicine, 21000 Split, Croatia;
- Department of Anatomy, School of Medicine, University of Mostar, 88000 Mostar, Bosnia and Herzegovina
- Department of Histology and Embryology, School of Medicine, University of Mostar, 88000 Mostar, Bosnia and Herzegovina;
- Faculty of Health Studies, University of Mostar, 88000 Mostar, Bosnia and Herzegovina
- Center for Translational Research in Biomedicine, University of Split School of Medicine, 21000 Split, Croatia
| | - Violeta Šoljić
- Department of Histology and Embryology, School of Medicine, University of Mostar, 88000 Mostar, Bosnia and Herzegovina;
- Faculty of Health Studies, University of Mostar, 88000 Mostar, Bosnia and Herzegovina
| | - Vlatka Martinović
- Department of Surgery, School of Medicine, University of Mostar, 88000 Mostar, Bosnia and Herzegovina;
| | - Fila Raguž
- Department of Internal Medicine, School of Medicine, University of Mostar, 88000 Mostar, Bosnia and Herzegovina;
| | - Natalija Filipović
- Department of Anatomy, Histology and Embryology, University of Split School of Medicine, 21000 Split, Croatia;
- Department of Anatomy, School of Medicine, University of Mostar, 88000 Mostar, Bosnia and Herzegovina
- Center for Translational Research in Biomedicine, University of Split School of Medicine, 21000 Split, Croatia
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14-3-3 Activated Bacterial Exotoxins AexT and ExoT Share Actin and the SH2 Domains of CRK Proteins as Targets for ADP-Ribosylation. Pathogens 2022; 11:pathogens11121497. [PMID: 36558830 PMCID: PMC9787417 DOI: 10.3390/pathogens11121497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 12/01/2022] [Accepted: 12/06/2022] [Indexed: 12/13/2022] Open
Abstract
Bacterial exotoxins with ADP-ribosyltransferase activity can be divided into distinct clades based on their domain organization. Exotoxins from several clades are known to modify actin at Arg177; but of the 14-3-3 dependent exotoxins only Aeromonas salmonicida exoenzyme T (AexT) has been reported to ADP-ribosylate actin. Given the extensive similarity among the 14-3-3 dependent exotoxins, we initiated a structural and biochemical comparison of these proteins. Structural modeling of AexT indicated a target binding site that shared homology with Pseudomonas aeruginosa Exoenzyme T (ExoT) but not with Exoenzyme S (ExoS). Biochemical analyses confirmed that the catalytic activities of both exotoxins were stimulated by agmatine, indicating that they ADP-ribosylate arginine residues in their targets. Side-by-side comparison of target protein modification showed that AexT had activity toward the SH2 domain of the Crk-like protein (CRKL), a known target for ExoT. We found that both AexT and ExoT ADP-ribosylated actin and in both cases, the modification compromised actin polymerization. Our results indicate that AexT and ExoT are functional homologs that affect cytoskeletal integrity via actin and signaling pathways to the cytoskeleton.
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Ikeda D, Chi S, Uchiyama S, Nakamura H, Guo YM, Yamauchi N, Yuda J, Minami Y. Molecular Classification and Overcoming Therapy Resistance for Acute Myeloid Leukemia with Adverse Genetic Factors. Int J Mol Sci 2022; 23:5950. [PMID: 35682627 PMCID: PMC9180585 DOI: 10.3390/ijms23115950] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 05/19/2022] [Accepted: 05/24/2022] [Indexed: 12/01/2022] Open
Abstract
The European LeukemiaNet (ELN) criteria define the adverse genetic factors of acute myeloid leukemia (AML). AML with adverse genetic factors uniformly shows resistance to standard chemotherapy and is associated with poor prognosis. Here, we focus on the biological background and real-world etiology of these adverse genetic factors and then describe a strategy to overcome the clinical disadvantages in terms of targeting pivotal molecular mechanisms. Different adverse genetic factors often rely on common pathways. KMT2A rearrangement, DEK-NUP214 fusion, and NPM1 mutation are associated with the upregulation of HOX genes. The dominant tyrosine kinase activity of the mutant FLT3 or BCR-ABL1 fusion proteins is transduced by the AKT-mTOR, MAPK-ERK, and STAT5 pathways. Concurrent mutations of ASXL1 and RUNX1 are associated with activated AKT. Both TP53 mutation and mis-expressed MECOM are related to impaired apoptosis. Clinical data suggest that adverse genetic factors can be found in at least one in eight AML patients and appear to accumulate in relapsed/refractory cases. TP53 mutation is associated with particularly poor prognosis. Molecular-targeted therapies focusing on specific genomic abnormalities, such as FLT3, KMT2A, and TP53, have been developed and have demonstrated promising results.
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Affiliation(s)
- Daisuke Ikeda
- Department of Hematology, National Cancer Center Hospital East, Kashiwa, Chiba 277-8577, Japan; (D.I.); (S.C.); (S.U.); (H.N.); (Y.-M.G.); (N.Y.); (J.Y.)
- Department of Hematology, Kameda Medical Center, Kamogawa 296-8602, Japan
| | - SungGi Chi
- Department of Hematology, National Cancer Center Hospital East, Kashiwa, Chiba 277-8577, Japan; (D.I.); (S.C.); (S.U.); (H.N.); (Y.-M.G.); (N.Y.); (J.Y.)
| | - Satoshi Uchiyama
- Department of Hematology, National Cancer Center Hospital East, Kashiwa, Chiba 277-8577, Japan; (D.I.); (S.C.); (S.U.); (H.N.); (Y.-M.G.); (N.Y.); (J.Y.)
| | - Hirotaka Nakamura
- Department of Hematology, National Cancer Center Hospital East, Kashiwa, Chiba 277-8577, Japan; (D.I.); (S.C.); (S.U.); (H.N.); (Y.-M.G.); (N.Y.); (J.Y.)
| | - Yong-Mei Guo
- Department of Hematology, National Cancer Center Hospital East, Kashiwa, Chiba 277-8577, Japan; (D.I.); (S.C.); (S.U.); (H.N.); (Y.-M.G.); (N.Y.); (J.Y.)
| | - Nobuhiko Yamauchi
- Department of Hematology, National Cancer Center Hospital East, Kashiwa, Chiba 277-8577, Japan; (D.I.); (S.C.); (S.U.); (H.N.); (Y.-M.G.); (N.Y.); (J.Y.)
| | - Junichiro Yuda
- Department of Hematology, National Cancer Center Hospital East, Kashiwa, Chiba 277-8577, Japan; (D.I.); (S.C.); (S.U.); (H.N.); (Y.-M.G.); (N.Y.); (J.Y.)
| | - Yosuke Minami
- Department of Hematology, National Cancer Center Hospital East, Kashiwa, Chiba 277-8577, Japan; (D.I.); (S.C.); (S.U.); (H.N.); (Y.-M.G.); (N.Y.); (J.Y.)
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Lozic M, Minarik L, Racetin A, Filipovic N, Saraga Babic M, Vukojevic K. CRKL, AIFM3, AIF, BCL2, and UBASH3A during Human Kidney Development. Int J Mol Sci 2021; 22:ijms22179183. [PMID: 34502088 PMCID: PMC8431184 DOI: 10.3390/ijms22179183] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 08/20/2021] [Accepted: 08/23/2021] [Indexed: 11/16/2022] Open
Abstract
We aimed to investigate the spatio-temporal expression of possible CAKUT candidate genes CRKL, AIFM3, and UBASH3A, as well as AIF and BCL2 during human kidney development. Human fetal kidney tissue was stained with antibodies and analyzed by fluorescence microscopy and RT-PCR. Quantification of positive cells was assessed by calculation of area percentage and counting cells in nephron structures. Results showed statistically significant differences in the temporal expression patterns of the examined markers, depending on the investigated developmental stage. Limited but strong expression of CRKL was seen in developing kidneys, with increasing expression up to the period where the majority of nephrons are formed. Results also lead us to conclude that AIFM3 and AIF are important for promoting cell survival, but only AIFM3 is considered a CAKUT candidate gene due to the lack of AIF in nephron developmental structures. Our findings imply great importance of AIFM3 in energy production in nephrogenesis and tubular maturation. UBASH3A raw scores showed greater immunoreactivity in developing structures than mature ones which would point to a meaningful role in nephrogenesis. The fact that mRNA and proteins of CRKL, UBASH3A, and AIFM3 were detected in all phases of kidney development implies their role as renal development control genes.
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Affiliation(s)
- Mirela Lozic
- Department of Anatomy, Histology and Embryology, School of Medicine, University of Split, Šoltanska 2, 21 000 Split, Croatia; (M.L.); (L.M.); (A.R.); (N.F.); (M.S.B.)
| | - Luka Minarik
- Department of Anatomy, Histology and Embryology, School of Medicine, University of Split, Šoltanska 2, 21 000 Split, Croatia; (M.L.); (L.M.); (A.R.); (N.F.); (M.S.B.)
| | - Anita Racetin
- Department of Anatomy, Histology and Embryology, School of Medicine, University of Split, Šoltanska 2, 21 000 Split, Croatia; (M.L.); (L.M.); (A.R.); (N.F.); (M.S.B.)
- Department of Medical Genetics, School of Medicine, University of Mostar, 88 000 Mostar, Bosnia and Herzegovina
| | - Natalija Filipovic
- Department of Anatomy, Histology and Embryology, School of Medicine, University of Split, Šoltanska 2, 21 000 Split, Croatia; (M.L.); (L.M.); (A.R.); (N.F.); (M.S.B.)
| | - Mirna Saraga Babic
- Department of Anatomy, Histology and Embryology, School of Medicine, University of Split, Šoltanska 2, 21 000 Split, Croatia; (M.L.); (L.M.); (A.R.); (N.F.); (M.S.B.)
| | - Katarina Vukojevic
- Department of Anatomy, Histology and Embryology, School of Medicine, University of Split, Šoltanska 2, 21 000 Split, Croatia; (M.L.); (L.M.); (A.R.); (N.F.); (M.S.B.)
- Department of Medical Genetics, School of Medicine, University of Mostar, 88 000 Mostar, Bosnia and Herzegovina
- Correspondence: ; Tel.: +385-21-557-807; Fax: +385-21-557-811
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Kim JH, Kim K, Kim I, Seong S, Kook H, Kim KK, Koh JT, Kim N. Bifunctional Role of CrkL during Bone Remodeling. Int J Mol Sci 2021; 22:ijms22137007. [PMID: 34209812 PMCID: PMC8269069 DOI: 10.3390/ijms22137007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 06/15/2021] [Accepted: 06/23/2021] [Indexed: 11/16/2022] Open
Abstract
Coupled signaling between bone-forming osteoblasts and bone-resorbing osteoclasts is crucial to the maintenance of bone homeostasis. We previously reported that v-crk avian sarcoma virus CT10 oncogene homolog-like (CrkL), which belongs to the Crk family of adaptors, inhibits bone morphogenetic protein 2 (BMP2)-mediated osteoblast differentiation, while enhancing receptor activator of nuclear factor kappa-B ligand (RANKL)-induced osteoclast differentiation. In this study, we investigated whether CrkL can also regulate the coupling signals between osteoblasts and osteoclasts, facilitating bone homeostasis. Osteoblastic CrkL strongly decreased RANKL expression through its inhibition of runt-related transcription factor 2 (Runx2) transcription. Reduction in RANKL expression by CrkL in osteoblasts resulted in the inhibition of not only osteoblast-dependent osteoclast differentiation but also osteoclast-dependent osteoblast differentiation, suggesting that CrkL participates in the coupling signals between osteoblasts and osteoclasts via its regulation of RANKL expression. Therefore, CrkL bifunctionally regulates osteoclast differentiation through both a direct and indirect mechanism while it inhibits osteoblast differentiation through its blockade of both BMP2 and RANKL reverse signaling pathways. Collectively, these data suggest that CrkL is involved in bone homeostasis, where it helps to regulate the complex interactions of the osteoblasts, osteoclasts, and their coupling signals.
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Affiliation(s)
- Jung Ha Kim
- Department of Pharmacology, Chonnam National University Medical School, Gwangju 61469, Korea; (J.H.K.); (K.K.); (I.K.); (S.S.); (H.K.); (K.K.K.)
- Hard-Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju 61186, Korea;
| | - Kabsun Kim
- Department of Pharmacology, Chonnam National University Medical School, Gwangju 61469, Korea; (J.H.K.); (K.K.); (I.K.); (S.S.); (H.K.); (K.K.K.)
| | - Inyoung Kim
- Department of Pharmacology, Chonnam National University Medical School, Gwangju 61469, Korea; (J.H.K.); (K.K.); (I.K.); (S.S.); (H.K.); (K.K.K.)
| | - Semun Seong
- Department of Pharmacology, Chonnam National University Medical School, Gwangju 61469, Korea; (J.H.K.); (K.K.); (I.K.); (S.S.); (H.K.); (K.K.K.)
- Hard-Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju 61186, Korea;
| | - Hyun Kook
- Department of Pharmacology, Chonnam National University Medical School, Gwangju 61469, Korea; (J.H.K.); (K.K.); (I.K.); (S.S.); (H.K.); (K.K.K.)
| | - Kyung Keun Kim
- Department of Pharmacology, Chonnam National University Medical School, Gwangju 61469, Korea; (J.H.K.); (K.K.); (I.K.); (S.S.); (H.K.); (K.K.K.)
| | - Jeong-Tae Koh
- Hard-Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju 61186, Korea;
- Department of Pharmacology and Dental Therapeutics, School of Dentistry, Chonnam National University, Gwangju 61186, Korea
| | - Nacksung Kim
- Department of Pharmacology, Chonnam National University Medical School, Gwangju 61469, Korea; (J.H.K.); (K.K.); (I.K.); (S.S.); (H.K.); (K.K.K.)
- Hard-Tissue Biointerface Research Center, School of Dentistry, Chonnam National University, Gwangju 61186, Korea;
- Correspondence: ; Tel.: +82-61-379-2835
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Song Q, Yi F, Zhang Y, Jun Li DK, Wei Y, Yu H, Zhang Y. CRKL regulates alternative splicing of cancer-related genes in cervical cancer samples and HeLa cell. BMC Cancer 2019; 19:499. [PMID: 31133010 PMCID: PMC6537309 DOI: 10.1186/s12885-019-5671-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 05/02/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Aberrant spliced isoforms are specifically associated with cancer progression and metastasis. The cytoplasmic adaptor CRKL (v-crk avian sarcoma virus CT10 oncogene homolog-like) is a CRK like proto-oncogene, which encodes a SH2 and SH3 (src homology) domain-containing adaptor protein. CRKL is tightly linked to leukemia via its binding partners BCR-ABL and TEL-ABL, upregulated in multiple types of human cancers, and induce cancer cell proliferation and invasion. However, it remains unclear whether signaling adaptors such as CRKL could regulate alternative splicing. METHODS We analyzed the expression level of CRKL in 305 cervical cancer tissue samples available in TCGA database, and then selected two groups of cancer samples with CRKL differentially expressed to analyzed potential CRKL-regulated alternative splicing events (ASEs). CRKL was knocked down by shRNA to further study CRKL-regulated alternative splicing and the activity of SR protein kinases in HeLa cells using RNA-Seq and Western blot techniques. We validated 43 CRKL-regulated ASEs detected by RNA-seq in HeLa cells, using RT-qPCR analysis of HeLa cell samples and using RNA-seq data of the two group of clinical cervical samples. RESULTS The expression of CRKL was mostly up-regulated in stage I cervical cancer samples. Knock-down of CRKL led to a reduced cell proliferation. CRKL-regulated alternative splicing of a large number of genes were enriched in cancer-related functional pathways, among which DNA repair and G2/M mitotic cell cycle, GnRH signaling were shared among the top 10 enriched GO terms and KEGG pathways by results from clinical samples and HeLa cell model. We showed that CRKL-regulated ASEs revealed by computational analysis using ABLas software in HeLa cell were highly validated by RT-qPCR, and also validated by cervical cancer clinical samples. CONCLUSIONS This is the first report of CRKL-regulation of the alternative splicing of a number of genes critical in tumorigenesis and cancer progression, which is consistent with CRKL reported role as a signaling adaptor and a kinase. Our results underline that the signaling adaptor CRKL might integrate the external and intrinsic cellular signals and coordinate the dynamic activation of cellular signaling pathways including alternative splicing regulation.
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Affiliation(s)
- Qingling Song
- Department of Oncology and Radiotherapy, Wuhan General Hospital of Guangzhou Military Command, Wuhan, 430070, Hubei Province, China
| | - Fengtao Yi
- Department of Oncology and Radiotherapy, Wuhan General Hospital of Guangzhou Military Command, Wuhan, 430070, Hubei Province, China.
| | - Yuhong Zhang
- Laboratory of Human Health and Genome Regulation, Wuhan, 430075, Hubei, China.,Center for Genome Analysis, ABLife Inc, Wuhan, 430075, Hubei, China
| | - Daniel K Jun Li
- Center for Genome Analysis, ABLife Inc, Wuhan, 430075, Hubei, China.,Department of Biology and Biotechnology, School of Chemistry, Chemical Engineering and Life Science, Wuhan University of Technology, Wuhan, 430070, Hubei, China
| | - Yaxun Wei
- Center for Genome Analysis, ABLife Inc, Wuhan, 430075, Hubei, China
| | - Han Yu
- Laboratory of Human Health and Genome Regulation, Wuhan, 430075, Hubei, China
| | - Yi Zhang
- Laboratory of Human Health and Genome Regulation, Wuhan, 430075, Hubei, China. .,Center for Genome Analysis, ABLife Inc, Wuhan, 430075, Hubei, China.
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Boettcher M, Tian R, Blau JA, Markegard E, Wagner RT, Wu D, Mo X, Biton A, Zaitlen N, Fu H, McCormick F, Kampmann M, McManus MT. Dual gene activation and knockout screen reveals directional dependencies in genetic networks. Nat Biotechnol 2018; 36:170-178. [PMID: 29334369 PMCID: PMC6072461 DOI: 10.1038/nbt.4062] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 12/20/2017] [Indexed: 02/08/2023]
Abstract
Understanding the direction of information flow is essential for characterizing how genetic networks affect phenotypes. However, methods to find genetic interactions largely fail to reveal directional dependencies. We combine two orthogonal Cas9 proteins from Streptococcus pyogenes and Staphylococcus aureus to carry out a dual screen in which one gene is activated while a second gene is deleted in the same cell. We analyse the quantitative effects of activation and knockout to calculate genetic interaction and directionality scores for each gene pair. Based on the results from over 100,000 perturbed gene pairs, we reconstruct a directional dependency network for human K562 leukemia cells and demonstrate how our approach allows the determination of directionality in activating genetic interactions. Our interaction network connects previously uncharacterised genes to well-studied pathways and identifies targets relevant for therapeutic intervention.
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Affiliation(s)
- Michael Boettcher
- Department of Microbiology and Immunology, University of California San Francisco Diabetes Center, WM Keck Center for Noncoding RNAs, University of California, San Francisco, San Francisco, California, USA
| | - Ruilin Tian
- Institute for Neurodegenerative Diseases, Department of Biochemistry and Biophysics, University of California, San Francisco and Chan Zuckerberg Biohub, San Francisco, California, USA
| | - James A Blau
- Department of Microbiology and Immunology, University of California San Francisco Diabetes Center, WM Keck Center for Noncoding RNAs, University of California, San Francisco, San Francisco, California, USA
| | - Evan Markegard
- Helen Diller Family Comprehensive Cancer Center, Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, California, USA
| | - Ryan T Wagner
- Department of Microbiology and Immunology, University of California San Francisco Diabetes Center, WM Keck Center for Noncoding RNAs, University of California, San Francisco, San Francisco, California, USA
| | - David Wu
- Department of Microbiology and Immunology, University of California San Francisco Diabetes Center, WM Keck Center for Noncoding RNAs, University of California, San Francisco, San Francisco, California, USA
| | - Xiulei Mo
- Department of Pharmacology and Emory Chemical Biology Discovery Center, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Anne Biton
- Department of Medicine, Lung Biology Center, University of California, San Francisco, San Francisco, California, USA.,Centre de Bioinformatique, Biostatistique et Biologie Intégrative (C3BI, USR 3756 Institut Pasteur et CNRS), Paris, France
| | - Noah Zaitlen
- Department of Medicine, Lung Biology Center, University of California, San Francisco, San Francisco, California, USA
| | - Haian Fu
- Department of Pharmacology and Emory Chemical Biology Discovery Center, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Frank McCormick
- Helen Diller Family Comprehensive Cancer Center, Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, California, USA
| | - Martin Kampmann
- Institute for Neurodegenerative Diseases, Department of Biochemistry and Biophysics, University of California, San Francisco and Chan Zuckerberg Biohub, San Francisco, California, USA
| | - Michael T McManus
- Department of Microbiology and Immunology, University of California San Francisco Diabetes Center, WM Keck Center for Noncoding RNAs, University of California, San Francisco, San Francisco, California, USA
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Expression and Production of SH2 Domain Proteins. Methods Mol Biol 2017. [PMID: 28092031 DOI: 10.1007/978-1-4939-6762-9_8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/06/2023]
Abstract
The Src Homology 2 (SH2) domain lies at the heart of phosphotyrosine signaling, coordinating signaling events downstream of receptor tyrosine kinases (RTKs), adaptors, and scaffolds. Over a hundred SH2 domains are present in mammals, each having a unique specificity which determines its interactions with multiple binding partners. One of the essential tools necessary for studying and determining the role of SH2 domains in phosphotyrosine signaling is a set of soluble recombinant SH2 proteins. Here we describe methods, based on a broad experience with purification of all SH2 domains, for the production of SH2 domain proteins needed for proteomic and biochemical-based studies such as peptide arrays, mass-spectrometry, protein microarrays, reverse-phase microarrays, and high-throughput fluorescence polarization (HTP-FP). We describe stepwise protocols for expression and purification of SH2 domains using GST or poly His-tags, two widely adopted affinity tags. In addition, we address alternative approaches, challenges, and validation studies for assessing protein quality and provide general characteristics of purified human SH2 domains.
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Inverse regulation of bridging integrator 1 and BCR-ABL1 in chronic myeloid leukemia. Tumour Biol 2016; 37:217-25. [PMID: 26194865 DOI: 10.1007/s13277-015-3772-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 07/07/2015] [Indexed: 12/14/2022] Open
Abstract
Endocytosis is the major regulator process of tyrosine kinase receptor (RTK) functional activities. Bridging integrator 1 (BIN1) is a key protein involved in RTK intracellular trafficking. Here, we report, by studying 34 patients with chronic myeloid leukemia (CML) at diagnosis, that BIN1 gene is downregulated in CML as compared to healthy controls, suggesting an altered endocytosis of RTKs. Rab interactor 1 (RIN1), an activator of BIN1, displayed a similar behavior. Treatment of 57 patients by tyrosine kinase inhibitors caused, along with BCR-ABL1 inactivation, an increase of BIN1 and RIN1 expression, potentially restoring endocytosis. There was a significant inverse correlation between BIN1-RIN1 and BCR-ABL1 expression. In vitro experiments on both CML and nontumorigenic cell lines treated with Imatinib confirmed these results. In order to provide another proof in favor of BIN1 and RIN1 endocytosis function in CML, we demonstrated that Imatinib induced, in K562 cell line, BIN1-RIN1 upregulation accompanied by a parallel AXL receptor internalization into cytoplasmic compartment. This study shows a novel deregulated mechanism in CML patients, indicating BIN1 and RIN1 as players in the maintenance of the abnormal RTK signaling in this hematological disease.
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Badger-Brown KM, Gillis LC, Bailey ML, Penninger JM, Barber DL. CBL-B is required for leukemogenesis mediated by BCR-ABL through negative regulation of bone marrow homing. Leukemia 2012; 27:1146-54. [DOI: 10.1038/leu.2012.331] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Genetic and functional studies of phosphatidyl-inositol 4-kinase type IIIα. Biochim Biophys Acta Mol Cell Biol Lipids 2011; 1811:476-83. [PMID: 21601653 DOI: 10.1016/j.bbalip.2011.04.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Revised: 03/23/2011] [Accepted: 04/26/2011] [Indexed: 12/22/2022]
Abstract
Phosphatidylinositol 4-kinase type IIIa (PI4KIIIα) is one of four mammalian PI 4-kinases that catalyzes the first committed step in polyphosphoinositide synthesis. PI4KIIIα has been linked to regulation of ER exit sites and to the synthesis of plasma membrane phosphoinositides and recent studies have also revealed its importance in replication of the Hepatitis C virus in liver. Two isoforms of the mammalian PI4KIIIα have been described and annotated in GenBank: a larger, ~230kDa (isoform 2) and a shorter splice variant containing only the ~97kDa C-terminus that includes the catalytic domain (isoform 1). However, Northern analysis of human tissues and cancer cells showed only a single transcript of ~7.5kb with the exception of the proerythroleukemia line K562, which contained significantly higher level of the 7.5kb transcript along with smaller ones of 2.4, 3.5 and 4.2kb size. Bioinformatic analysis also confirmed the high copy number of PI4KIIIα transcript in K562 cells along with several genes located in the same region in Chr22, including two pseudogenes that cover most exons coding for isoform 1, consistent with chromosome amplification. A panel of polyclonal antibodies raised against peptides within the C-terminal half of PI4KIIIα failed to detect the shorter isoform 1 either in COS-7 cells or K562 cells. Moreover, expression of a cDNA encoding isoform 1 yielded a protein of ~97kDa that showed no catalytic activity and failed to rescue hepatitis C virus replication. These data draw attention to PI4KIIIα as one of the genes found in Chr22q11, a region affected by chromosomal instability, but do not substantiate the existence of a functionally relevant short form of PI4KIIIα.
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Ogawa S, Shih LY, Suzuki T, Otsu M, Nakauchi H, Koeffler HP, Sanada M. Deregulated Intracellular Signaling by Mutated c-CBL in Myeloid Neoplasms. Clin Cancer Res 2010; 16:3825-31. [DOI: 10.1158/1078-0432.ccr-09-2341] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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13
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Ogawa S, Sanada M, Shih LY, Suzuki T, Otsu M, Nakauchi H, Koeffler HP. Gain-of-function c-CBL mutations associated with uniparental disomy of 11q in myeloid neoplasms. Cell Cycle 2010; 9:1051-6. [PMID: 20237427 DOI: 10.4161/cc.9.6.11034] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
c-CBL (CBL) encodes a multifunctional protein engaged in the regulation of intracellular signaling pathways. It was first identified as a cellular counterpart of the viral oncogene, v-CBL, that causes murine lymphoma. Although no genetic evidence existed suggesting its role in human carcinogenesis, the recent discovery of c-CBL mutations in myeloid cancers has unveiled a unique oncogenic mechanism mediated by gain-of-function of a mutated tumor suppressor, closely associated with allelic conversion of 11q arms. In this review, we summarize our current knowledge about c-CBL mutations and discuss the molecular mechanisms of their gain-of-function.
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Affiliation(s)
- Seishi Ogawa
- Cancer Genomics Project, University of Tokyo, Bunkyo-ku, Tokyo, Japan.
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14
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Antoku S, Saksela K, Rivera GM, Mayer BJ. A crucial role in cell spreading for the interaction of Abl PxxP motifs with Crk and Nck adaptors. J Cell Sci 2008; 121:3071-82. [PMID: 18768933 DOI: 10.1242/jcs.031575] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The dynamic reorganization of actin structures helps to mediate the interaction of cells with their environment. The Abl non-receptor tyrosine kinase can modulate actin rearrangement during cell attachment. Here we report that the Abl PxxP motifs, which bind Src homology 3 (SH3) domains, are indispensable for the coordinated regulation of filopodium and focal adhesion formation and cell-spreading dynamics during attachment. Candidate Abl PxxP-motif-binding partners were identified by screening a comprehensive SH3-domain phage-display library. A combination of protein overexpression, silencing, pharmacological manipulation and mutational analysis demonstrated that the PxxP motifs of Abl exert their effects on actin organization by two distinct mechanisms, involving the inhibition of Crk signaling and the engagement of Nck. These results uncover a previously unappreciated role for Abl PxxP motifs in the regulation of cell spreading.
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Affiliation(s)
- Susumu Antoku
- Department of Genetics and Developmental Biology, University of Connecticut Health Center, Farmington, CT 06030-3301 USA
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15
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Tyrosine phosphorylation of the nuclear receptor coactivator AIB1/SRC-3 is enhanced by Abl kinase and is required for its activity in cancer cells. Mol Cell Biol 2008; 28:6580-93. [PMID: 18765637 DOI: 10.1128/mcb.00118-08] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Overexpression and activation of the steroid receptor coactivator amplified in breast cancer 1 (AIB1)/steroid receptor coactivator-3 (SRC-3) have been shown to have a critical role in oncogenesis and are required for both steroid and growth factor signaling in epithelial tumors. Here, we report a new mechanism for activation of SRC coactivators. We demonstrate regulated tyrosine phosphorylation of AIB1/SRC-3 at a C-terminal tyrosine residue (Y1357) that is phosphorylated after insulin-like growth factor 1, epidermal growth factor, or estrogen treatment of breast cancer cells. Phosphorylated Y1357 is increased in HER2/neu (v-erb-b2 erythroblastic leukemia viral oncogene homolog 2) mammary tumor epithelia and is required to modulate AIB1/SRC-3 coactivation of estrogen receptor alpha (ERalpha), progesterone receptor B, NF-kappaB, and AP-1-dependent promoters. c-Abl (v-Abl Abelson murine leukemia viral oncogene homolog 1) tyrosine kinase directly phosphorylates AIB1/SRC-3 at Y1357 and modulates the association of AIB1 with c-Abl, ERalpha, the transcriptional cofactor p300, and the methyltransferase coactivator-associated arginine methyltransferase 1, CARM1. AIB1/SRC-3-dependent transcription and phenotypic changes, such as cell growth and focus formation, can be reversed by an Abl kinase inhibitor, imatinib. Thus, the phosphorylation state of Y1357 can function as a molecular on/off switch and facilitates the cross talk between hormone, growth factor, and intracellular kinase signaling pathways in cancer.
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16
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Abstract
Osteoclasts are multinucleated cells derived from hematopoietic precursors that are primarily responsible for the degradation of mineralized bone during bone development, homeostasis and repair. In various skeletal disorders such as osteoporosis, hypercalcemia of malignancy, tumor metastases and Paget's disease, bone resorption by osteoclasts exceeds bone formation by osteoblasts leading to decreased bone mass, skeletal fragility and bone fracture. The overall rate of osteoclastic bone resorption is regulated either at the level of differentiation of osteoclasts from their monocytic/macrophage precursor pool or through the regulation of key functional proteins whose specific activities in the mature osteoclast control its attachment, migration and resorption. Thus, reducing osteoclast numbers and/or decreasing the bone resorbing activity of osteoclasts are two common therapeutic approaches for the treatment of hyper-resorptive skeletal diseases. In this review, several of the key functional players involved in the regulation of osteoclast activity will be discussed.
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Affiliation(s)
- Angela Bruzzaniti
- Department of Orthopaedics, Yale University School of Medicine, New Haven, CT 06510, USA.
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17
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Cho YJ, Hemmeryckx B, Groffen J, Heisterkamp N. Interaction of Bcr/Abl with C3G, an exchange factor for the small GTPase Rap1, through the adapter protein Crkl. Biochem Biophys Res Commun 2005; 333:1276-83. [PMID: 15982636 DOI: 10.1016/j.bbrc.2005.06.030] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2005] [Accepted: 06/08/2005] [Indexed: 11/22/2022]
Abstract
The Bcr/Abl oncoprotein is directly responsible for the development of chronic myelogenous leukemia and Philadelphia chromosome-positive acute lymphoblastic leukemia in humans. The adapter protein Crkl is one of the most prominently tyrosine-phosphorylated substrates of Bcr/Abl in cells and tissues isolated from such patients. The guanine nucleotide exchange factor for the small GTPase Rap1, C3G, binds constitutively to Crkl. Here, we report that Crkl mediates the formation of protein complexes that include C3G and Bcr/Abl. These complexes contain highly elevated levels of tyrosine-phosphorylated C3G and P130Cas, a scaffolding protein. Moreover, the presence of Rap1 further promoted tyrosine phosphorylation of C3G and Cas. Co-expression of Crkl and C3G with Bcr/Abl generated increased levels of activated Rap1. In addition, lysates from leukemic cells of P190 BCR/ABL transgenic mice and of the myelogenous leukemia cell line K562 contained tyrosine-phosphorylated C3G and activated Rap1. These data suggest a role for C3G-mediated Rap1 activation in Bcr/Abl-induced leukemia development.
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Affiliation(s)
- Young Jin Cho
- Section of Molecular Carcinogenesis, Division of Hematology/Oncology, Childrens Hospital Los Angeles Saban Research Institute, 4650 Sunset Boulevard, Los Angeles, CA 90027, USA
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18
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Machida K, Mayer BJ. The SH2 domain: versatile signaling module and pharmaceutical target. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2005; 1747:1-25. [PMID: 15680235 DOI: 10.1016/j.bbapap.2004.10.005] [Citation(s) in RCA: 139] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2004] [Revised: 09/29/2004] [Accepted: 10/11/2004] [Indexed: 10/26/2022]
Abstract
The Src homology 2 (SH2) domain is the most prevalent protein binding module that recognizes phosphotyrosine. This approximately 100-amino-acid domain is highly conserved structurally despite being found in a wide variety proteins. Depending on the nature of neighboring protein module(s), such as catalytic domains and other protein binding domains, SH2-containing proteins play many different roles in cellular protein tyrosine kinase (PTK) signaling pathways. Accumulating evidence indicates SH2 domains are highly versatile and exhibit considerable flexibility in how they bind to their ligands. To illustrate this functional versatility, we present three specific examples: the SAP, Cbl and SOCS families of SH2-containing proteins, which play key roles in immune responses, termination of PTK signaling, and cytokine responses. In addition, we highlight current progress in the development of SH2 domain inhibitors designed to antagonize or modulate PTK signaling in human disease. Inhibitors of the Grb2 and Src SH2 domains have been extensively studied, with the aim of targeting the Ras pathway and osteoclastic bone resorption, respectively. Despite formidable difficulties in drug design due to the lability and poor cell permeability of negatively charged phosphorylated SH2 ligands, a variety of structure-based strategies have been used to reduce the size, charge and peptide character of such ligands, leading to the development of high-affinity lead compounds with potent cellular activities. These studies have also led to new insights into molecular recognition by the SH2 domain.
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Affiliation(s)
- Kazuya Machida
- Raymond and Beverly Sackler Laboratory of Genetics and Molecular Medicine, Department of Genetics and Developmental Biology, University of Connecticut Health Center, 263 Farmington Avenue, Farmington, CT 06030-3301, USA.
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19
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Gaston I, Johnson KJ, Oda T, Bhat A, Reis M, Langdon W, Shen L, Deininger MW, Druker BJ. Coexistence of phosphotyrosine-dependent and -independent interactions between Cbl and Bcr-Abl. Exp Hematol 2004; 32:113-21. [PMID: 14725908 DOI: 10.1016/j.exphem.2003.09.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Cbl is one of the major tyrosine-phosphorylated proteins in Bcr-Abl-expressing cells. A direct association between the SH2 domain of Bcr-Abl and tyrosine-phosphorylated Cbl has been demonstrated. The purpose of this study was to determine if and how unphosphorylated Cbl and Bcr-Abl may associate. Interactions between Cbl and Bcr-Abl were investigated in yeast two- and three-hybrid systems, gel overlay assays, and immunoprecipitates from mammalian cells expressing wild-type and the Y177F mutant of Bcr-Abl. No direct interaction between Bcr-Abl and unphosphorylated Cbl was observed. Bcr-Abl did, however, associate with Grb2, an adaptor protein that binds tyrosine 177 of Bcr-Abl. Additionally, Grb2 interacted with Cbl. In a yeast three-hybrid assay, Grb2 mediated an interaction between Cbl and Bcr-Abl that was dependent on a functional Grb2 binding site. This interaction was confirmed in vitro using purified proteins. In cells expressing Bcr-Abl with a mutation in the Grb2 binding site, binding of Cbl to Bcr-Abl was significantly reduced, but Cbl tyrosine phosphorylation was maintained. Imatinib treatment of these cells further reduced but did not abrogate Cbl binding, reflecting residual kinase activity. Multiple phosphotyrosine-dependent and -independent interactions stabilize the interaction between Cbl and Abl. Grb2 or another, yet unidentified, protein may mediate an initial interaction between Cbl and Bcr-Abl that is independent of Cbl tyrosine phosphorylation. Following this initial interaction, Cbl can then become tyrosine phosphorylated and interact with the SH2 domain of Bcr-Abl, further stabilizing the complex.
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Affiliation(s)
- Isabelle Gaston
- Department of Molecular Microbiology and Immunology, Oregon Health and Science University, Portland, Ore. 97239, USA
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20
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Dinulescu DM, Wood LJ, Shen L, Loriaux M, Corless CL, Gross AW, Ren R, Deininger MWN, Druker BJ. c-CBL is not required for leukemia induction by Bcr-Abl in mice. Oncogene 2003; 22:8852-60. [PMID: 14654781 DOI: 10.1038/sj.onc.1206892] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Bcr-Abl tyrosine kinase activity is essential for the pathogenesis of chronic myeloid leukemia (CML). A number of Bcr-Abl substrates have been identified, but it is not clear which of these substrates are required for Bcr-Abl to transform cells. The multifunctional protein c-Cbl is one of the most prominently tyrosine-phosphorylated proteins in Bcr-Abl-expressing cells. Using cell lines and mice with homozygous disruption of the c-CBL locus, we investigated the role of this protein for Bcr-Abl-driven transformation. We find that although c-Cbl(-/-) fibroblast cell lines show a deficit in Bcr-Abl transformation compared to wild-type (Wt) cells, this deficit was less pronounced in c-Cbl(-/-) B cells derived from murine bone marrow. Most importantly, in a transplantation model of CML, Bcr-Abl was capable of inducing fatal leukemia in mice in the absence of c-Cbl protein. Our results indicate that c-Cbl is dispensable for Bcr-Abl-induced leukemogenesis in mice.
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21
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Nishihara T, Miura Y, Tohyama Y, Mizutani C, Hishita T, Ichiyama S, Uchiyama T, Tohyama K. Effects of the Tyrosine Kinase Inhibitor Imatinib Mesylate on a Bcr-Abl-Positive Cell Line: Suppression of Autonomous Cell Growth but No Effect on Decreased Adhesive Property and Morphological Changes. Int J Hematol 2003; 78:233-40. [PMID: 14604282 DOI: 10.1007/bf02983800] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Expression of the Bcr-Abl oncoprotein alters various aspects of hematopoietic cells. We investigated the effects of a Bcr-Abl tyrosine kinase inhibitor, imatinib mesylate, on the proliferation, adhesive properties, and morphology of a Bcr-Abl-transferred cell line, TF-1 Bcr-Abl, in comparison with parental TF-1. First, the factor-independent growth of TF-1 Bcr-Abl was inhibited in the presence of imatinib mesylate, but this inhibition was overcome by addition of exogenous granulocyte-macrophage colony-stimulating factor. Imatinib mesylate remarkably reduced tyrosine phosphorylation of Bcr-Abl, Cbl, and Crkl in a time-dependent manner, and their complex formation also was affected. Imatinib mesylate inhibited activation of Stat5 rather than the MEK-ERK1/2 pathway. TF-1 Bcr-Abl cells exhibited a round shape, unlike TF-1, and the adhesive property to fibronectin was much lower than that of TF-1. Although the Bcr-Abl oncoprotein may be involved negatively in cell adhesion, the decreased adhesion and altered morphology of TF-1 Bcr-Abl cells were minimally affected by imatinib mesylate and seemed independent of Bcr-Abl kinase activity. The present data indicated that the Bcr-Abl-specific kinase inhibitor cannot control Bcr-Abl-induced cell alterations other than autonomous growth.
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Affiliation(s)
- Toshio Nishihara
- Department of Hematology and Oncology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
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22
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Chien W, Tidow N, Williamson EA, Shih LY, Krug U, Kettenbach A, Fermin AC, Roifman CM, Koeffler HP. Characterization of a myeloid tyrosine phosphatase, Lyp, and its role in the Bcr-Abl signal transduction pathway. J Biol Chem 2003; 278:27413-20. [PMID: 12764153 DOI: 10.1074/jbc.m304575200] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Bcr-Abl protein-tyrosine kinase is implicated in the development of chronic myeloid leukemia. The potential role of protein-tyrosine phosphatase in the regulation of Bcr-Abl signaling was explored. First, expression patterns of tyrosine phosphatases in leukemic cell lines were investigated using degenerate primers for reverse transcription-PCR followed by cloning and sequencing of the cDNA. Distinct patterns of distribution of phosphatase were found in erythroid and myeloid leukemic cell lines. Whereas some phosphatases were ubiquitously expressed, others were limited to specific cell types. Surprisingly, a previously cloned "lymphocyte-specific" phosphatase, Lyp, was frequently detected in a number of myeloid cell lines as well as normal granulocytes and monocytes. Lyp was localized to the cytosol, and overexpression of Lyp caused reduction in the phosphorylation levels of multiple proteins in KCL22 chronic myeloid leukemia blast cells including Cbl, Bcr-Abl, Erk1/2, and CrkL. Co-expression of Lyp and Bcr-Abl in Cos-7 cells resulted in decreased levels of Bcr-Abl, Grb2, and Myc. Overexpression of Lyp markedly suppressed anchorage-independent clonal growth of KCL22 cells. Taken together, the data suggest that Lyp may play an antagonistic role in signaling by the Bcr-Abl fusion protein.
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Affiliation(s)
- Wenwen Chien
- Department of Hematology/Oncology, Cedars-Sinai Medical Center, UCLA School of Medicine, Los Angeles, California 90048, USA.
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23
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Clarkson B, Strife A, Wisniewski D, Lambek CL, Liu C. Chronic myelogenous leukemia as a paradigm of early cancer and possible curative strategies. Leukemia 2003; 17:1211-62. [PMID: 12835715 DOI: 10.1038/sj.leu.2402912] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The chronological history of the important discoveries leading to our present understanding of the essential clinical, biological, biochemical, and molecular features of chronic myelogenous leukemia (CML) are first reviewed, focusing in particular on abnormalities that are responsible for the massive myeloid expansion. CML is an excellent target for the development of selective treatment because of its highly consistent genetic abnormality and qualitatively different fusion gene product, p210(bcr-abl). It is likely that the multiple signaling pathways dysregulated by p210(bcr-abl) are sufficient to explain all the initial manifestations of the chronic phase of the disease, although understanding of the circuitry is still very incomplete. Evidence is presented that the signaling pathways that are constitutively activated in CML stem cells and primitive progenitors cooperate with cytokines to increase the proportion of stem cells that are activated and thereby increase recruitment into the committed progenitor cell pool, and that this increased activation is probably the primary cause of the massive myeloid expansion in CML. The cooperative interactions between Bcr-Abl and cytokine-activated pathways interfere with the synergistic interactions between multiple cytokines that are normally required for the activation of stem cells, while at the same time causing numerous subtle biochemical and functional abnormalities in the later progenitors and precursor cells. The committed CML progenitors have discordant maturation and reduced proliferative capacity compared to normal committed progenitors, and like them, are destined to die after a limited number of divisions. Thus, the primary goal of any curative strategy must be to eliminate all Philadelphia positive (Ph+) primitive cells that are capable of symmetric division and thereby able to expand the Ph+ stem cell pool and recreate the disease. Several highly potent and moderately selective inhibitors of Bcr-Abl kinase have recently been discovered that are capable of killing the majority of actively proliferating early CML progenitors with minimal effects on normal progenitors. However, like their normal counterparts, most of the CML primitive stem cells are quiescent at any given time and are relatively invulnerable to the Bcr-Abl kinase inhibitors as well as other drugs. We propose that survival of dormant Ph+ stem cells may be the most important reason for the inability to cure the disease during initial treatment, while resistance to the inhibitors and other drugs becomes increasingly important later. An outline of a possible curative strategy is presented that attempts to take advantage of the subtle differences in the proliferative behavior of normal and Ph+ stem cells and the newly discovered selective inhibitors of Bcr-Abl. Leukemia (2003) 17, 1211-1262. doi:10.1038/sj.leu.2402912
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MESH Headings
- Antineoplastic Agents/therapeutic use
- Fusion Proteins, bcr-abl/antagonists & inhibitors
- Fusion Proteins, bcr-abl/genetics
- Hematopoietic Stem Cells/pathology
- Humans
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/etiology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/therapy
- Signal Transduction
- Treatment Outcome
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Affiliation(s)
- B Clarkson
- Molecular Pharmacology and Chemistry Program, Sloan-Kettering Institute for Cancer Research, New York, NY 10021, USA
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24
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Wang L, Rudert WA, Loutaev I, Roginskaya V, Corey SJ. Repression of c-Cbl leads to enhanced G-CSF Jak-STAT signaling without increased cell proliferation. Oncogene 2002; 21:5346-55. [PMID: 12149655 DOI: 10.1038/sj.onc.1205670] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2001] [Revised: 05/09/2002] [Accepted: 05/14/2002] [Indexed: 11/09/2022]
Abstract
Engagement of the Granulocyte-Colony-Stimulating Factor (G-CSF) receptor activates non-receptor protein tyrosine kinases Lyn and Jak2. We found that Lyn-deficient DT40 cells that express the G-CSF receptor (DT40GR) do not demonstrate G-CSF-induced mitogenic signaling. Lyn associates with and phosphorylates a small set of molecules, including c-Cbl. c-Cbl is an adaptor involved in cell growth and cytoskeletal reorganization, predominantly in hematopoietic cells. Using yeast two-hybrid analysis, we found that c-Cbl directly couples Lyn to PI 3-kinase. We also found that expression of the c-CblY731F mutant, which uncouples PI 3-kinase, resulted in the inhibition of G-CSF-induced proliferative signaling in DT40GR cells. As a complementary strategy, we sought to analyse the effects of c-Cbl deficiency in DT40GR cells. We isolated, cloned and sequenced the full-length cDNA for chicken c-Cbl and constructed antisense vectors. Antisense inhibition of c-Cbl expression in DT40GR cells led to enhanced Jak-STAT activation following G-CSF stimulation. Yet, this enhancement of Jak-STAT activation was associated with decreased G-CSF-induced PI 3-kinase activity and DNA synthesis. PI 3-kinase activity correlated with DNA synthesis and physiological levels of c-Cbl. Together, these data suggest that physiologic level of c-Cbl provides a growth stimulatory pathway for G-CSF and that enhanced Jak-STAT activation is not sufficient for G-CSF-induced growth.
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Affiliation(s)
- Lin Wang
- Department of Pediatrics, Children's Hospital of Pittsburgh, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
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25
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Scheijen B, Griffin JD. Tyrosine kinase oncogenes in normal hematopoiesis and hematological disease. Oncogene 2002; 21:3314-33. [PMID: 12032772 DOI: 10.1038/sj.onc.1205317] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Tyrosine kinase oncogenes are formed as a result of mutations that induce constitutive kinase activity. Many of these tyrosine kinase oncogenes that are derived from genes, such as c-Abl, c-Fes, Flt3, c-Fms, c-Kit and PDGFRbeta, that are normally involved in the regulation of hematopoiesis or hematopoietic cell function. Despite differences in structure, normal function, and subcellular location, many of the tyrosine kinase oncogenes signal through the same pathways, and typically enhance proliferation and prolong viability. They represent excellent potential drug targets, and it is likely that additional mutations will be identified in other kinases, their immediate downstream targets, or in proteins regulating their function.
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Affiliation(s)
- Blanca Scheijen
- Department of Adult Oncology, Dana-Farber Cancer Institute, 44 Binney Street, Boston, Massachusetts, MA 02115, USA
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26
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Kin Y, Li G, Shibuya M, Maru Y. The Dbl homology domain of BCR is not a simple spacer in P210BCR-ABL of the Philadelphia chromosome. J Biol Chem 2001; 276:39462-8. [PMID: 11502748 DOI: 10.1074/jbc.m105484200] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Dbl homology (DH) domain of BCR in P210BCR-ABL (P210/WT) has been thought to have a negative effect on the activation of BCR-ABL because P185BCR-ABL, in which this region is physically deleted, has stronger biochemical and biological activities. To study the role of the DH domain of BCR in the background of P210/WT, the region was replaced with homologous sequences derived from Dbl (P210/Dbl) or CDC24 (P210/CDC24) or with irrelevant sequences from LacZ (P210/LacZ) or luciferase (P210/Luci). Surprisingly, the abilities to transform Rat1 cells or mouse bone marrow cells and induce growth factor independence in interleukin 3-dependent mouse Ba/F3 cells were retained only in P210/Dbl. However, even P210/Dbl could not achieve the wild type level of surviving potential against genotoxins in Rat1 cells and in Ba/F3 cells. Activation of Akt correlated with the biological changes in Rat1 cells but did not correlate with the biological changes in Ba/F3 cells. The DH domain was not tyrosine-phosphorylated in vitro, nor could we find any differences in peptide mapping between in vitro phosphorylated P210/WT and P210/Dbl. Although functions of the DH domain remain to be discovered, we propose that the DH domain makes positive contributions to P210BCR-ABL.
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Affiliation(s)
- Y Kin
- Department of Genetics, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-0071, Japan
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27
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Abstract
Crk family adaptors are widely expressed and mediate the timely formation of signal transduction protein complexes upon a variety of extracellular stimuli, including various growth and differentiation factors. Selective formation of multi-protein complexes by the Crk and Crk-like (CRKL) proteins depends on specific motifs recognized by their SH2 and SH3 domains. In the case of the first SH3 domains [SH3(1)] a P-x-x-P-x-K motif is crucial for highly selective binding, while the SH2 domains prefer motifs which conform to the consensus pY-x-x-P. Crk family proteins are involved in the relocalization and activation of several different effector proteins which include guanine nucleotide releasing proteins like C3G, protein kinases of the Abl- and GCK-families and small GTPases like Rap1 and Rac. Crk-type proteins have been found not only in vertebrates but also in flies and nematodes. Major insight into the function of Crk within organisms came from the genetic model organism C. elegans, where the Crk-homologue CED-2 regulates cell engulfment and phagocytosis. Other biological outcomes of the Crk-activated signal transduction cascades include the modulation of cell adhesion, cell migration and immune cell responses. Crk family adaptors also appear to play a role in mediating the action of human oncogenes like the leukaemia-inducing Bcr-Abl protein. This review summarizes some key findings and highlights recent insights and open questions.
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Affiliation(s)
- S M Feller
- Cell Signalling Laboratory, Imperial Cancer Research Fund, University of Oxford, Institute of Molecular Medicine, John Radcliffe Hospital, Headington, Oxford OX3 9DS, UK.
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28
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Tsygankov AY, Teckchandani AM, Feshchenko EA, Swaminathan G. Beyond the RING: CBL proteins as multivalent adapters. Oncogene 2001; 20:6382-402. [PMID: 11607840 DOI: 10.1038/sj.onc.1204781] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Following discovery of c-Cbl, a cellular form of the transforming retroviral protein v-Cbl, multiple Cbl-related proteins have been identified in vertebrate and invertebrate organisms. c-Cbl and its homologues are capable of interacting with numerous proteins involved in cell signaling, including various molecular adapters and protein tyrosine kinases. It appears that Cbl proteins play several functional roles, acting both as multivalent adapters and inhibitors of various protein tyrosine kinases. The latter function is linked, to a substantial extent, to the E3 ubiquitin-ligase activity of Cbl proteins. Experimental evidence for these functions, interrelations between them, and their biological significance are addressed in this review, with the main accent placed on the adapter functions of Cbl proteins.
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Affiliation(s)
- A Y Tsygankov
- Department of Microbiology and Immunology, Temple University School of Medicine, Philadelphia, Pennsylvania, PA 19140, USA.
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29
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Nguyen MH, Ho JM, Beattie BK, Barber DL. TEL-JAK2 mediates constitutive activation of the phosphatidylinositol 3'-kinase/protein kinase B signaling pathway. J Biol Chem 2001; 276:32704-13. [PMID: 11435425 DOI: 10.1074/jbc.m103100200] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A subset of chromosomal translocations that participate in leukemia involve activated tyrosine kinases. The ets transcription factor, TEL, undergoes translocations with several distinct tyrosine kinases including JAK2. TEL-JAK2 transforms cell lines to factor independence, and constitutive tyrosine kinase activity results in the phosphorylation of several substrates including STAT1, STAT3, and STAT5. In this study we have shown that TEL-JAK2 can constitutively activate the phosphatidylinositol 3'-kinase (PI 3'-kinase) signaling pathway. The regulatory subunit of PI 3'-kinase, p85, associates with TEL-JAK2 in immunoprecipitations, and this was shown to be mediated by the amino-terminal SH2 domain of p85 but independent of a putative p85-binding motif within TEL-JAK2. The scaffolding protein Gab2 can also mediate the association of p85. TEL-JAK2 constitutively phosphorylates the downstream substrate protein kinase B/AKT. Importantly, the pharmacologic PI 3'-kinase inhibitor, LY294002, blocked TEL-JAK2 factor-independent growth and phosphorylation of protein kinase B. However, LY294002 did not alter STAT5 tyrosine phosphorylation, indicating that STAT5 and protein kinase B activation mediated by TEL-JAK2 are independent signaling pathways. Therefore, activation of the PI 3'-kinase signaling pathway is an important event mediated by TEL-JAK2 chromosomal translocations.
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Affiliation(s)
- M H Nguyen
- Division of Cellular and Molecular Biology, Ontario Cancer Institute, University Health Network, Toronto, Ontario M5G 2M9, Canada
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30
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Miyoshi-Akiyama T, Aleman LM, Smith JM, Adler CE, Mayer BJ. Regulation of Cbl phosphorylation by the Abl tyrosine kinase and the Nck SH2/SH3 adaptor. Oncogene 2001; 20:4058-69. [PMID: 11494134 DOI: 10.1038/sj.onc.1204528] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2000] [Revised: 04/02/2001] [Accepted: 04/09/2001] [Indexed: 11/08/2022]
Abstract
The Cbl proto-oncogene product is tyrosine phosphorylated in response to a wide variety of stimuli. Cbl and the Abl nonreceptor tyrosine kinase both bind to SH3 domains from the SH2/SH3 adaptor Nck, and are candidate effectors for Nck function. Numerous additional SH2- and SH3-domain-mediated interactions are also possible between Cbl, Abl, and Nck. We find that these three signaling proteins associate when overexpressed in mammalian cells and can regulate each other's activity. Co-expression of wt Cbl together with c-Abl, the activity of which is normally repressed in vivo, led to extensive Abl-dependent phosphorylation of Cbl. The major proline-rich region of Cbl was required for its phosphorylation by c-Abl, but not by a constitutively activated Abl mutant, suggesting Cbl activates c-Abl by engaging its SH3 domain. Efficient phosphorylation of Cbl and its stable association with Abl required the SH2 domain of Abl, suggesting that SH2-phosphotyrosine interactions prevent dissociation of active Abl from Cbl. We also show that overexpression of Nck could repress the phosphorylation of Cbl by Abl in vivo. Studies with Nck mutants suggested that the Nck SH2 domain is responsible for inhibiting the activity of Abl toward both Cbl and Nck itself, most likely by competing with the Abl SH2 for tyrosine-phosphorylated binding sites.
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Affiliation(s)
- T Miyoshi-Akiyama
- Laboratory of Molecular Medicine, Children's Hospital and Department of Microbiology and Molecular Genetics, Harvard Medical School, 300 Longwood Avenue, Boston, Massachusetts, MA 02115, USA
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31
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Verfaillie CATHERINEM, Gupta PANKAJ, Prosper FELIPE, Hurley RANDY, Lundell BEVERLY, Bhatia RAVI. The Hematopoietic Microenvironment: Stromal Extracellular Matrix Components As Growth Regulators For Human Hematopoietic Progenitors. HEMATOLOGY (AMSTERDAM, NETHERLANDS) 2001; 4:321-333. [PMID: 11399573 DOI: 10.1080/10245332.1999.11746456] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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32
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Abstract
Responses to extracellular stimuli are often transduced from cell-surface receptors to protein tyrosine kinases which, when activated, initiate the formation of protein complexes that transmit signals throughout the cell. A prominent component of these complexes is the product of the proto-oncogene c-Cbl, which specifically targets activated protein tyrosine kinases and regulates their signalling. How, then, does this multidomain protein shape the responses generated by these signalling complexes?
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Affiliation(s)
- C B Thien
- Department of Pathology, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009, Australia
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33
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Abstract
The Philadelphia chromosome generates a chimeric oncogene in which the BCR and c-ABL genes are fused. The product of this oncogene, BCR/ABL, has elevated ABL tyrosine kinase activity, relocates to the cytoskeleton, and phosphorylates multiple cellular substrates. BCR/ABL transforms hematopoietic cells and exerts a wide variety of biological effects, including reduction in growth factor dependence, enhanced viability, and altered adhesion of chronic myelocytic leukemia (CML) cells. Elevated tyrosine kinase activity of BCR/ABL is critical for activating downstream signal transduction and for all aspects of transformation. This review will describe mechanisms of transformation by the BCR/ABL oncogene and opportunities for clinical intervention with specific signal transduction inhibitors such as STI-571 in CML.
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MESH Headings
- Benzamides
- Cell Transformation, Neoplastic/genetics
- Cytoskeleton/metabolism
- Enzyme Activation
- Enzyme Inhibitors/pharmacology
- Enzyme Inhibitors/therapeutic use
- Fusion Proteins, bcr-abl/antagonists & inhibitors
- Fusion Proteins, bcr-abl/chemistry
- Fusion Proteins, bcr-abl/genetics
- Fusion Proteins, bcr-abl/physiology
- Humans
- Imatinib Mesylate
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/enzymology
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics
- Models, Biological
- Oncogene Proteins, Fusion/genetics
- Oncogene Proteins, Fusion/physiology
- Philadelphia Chromosome
- Phosphorylation
- Piperazines/pharmacology
- Piperazines/therapeutic use
- Protein Processing, Post-Translational
- Protein Structure, Tertiary
- Protein Transport
- Pyrimidines/pharmacology
- Pyrimidines/therapeutic use
- Reactive Oxygen Species
- Signal Transduction/physiology
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Affiliation(s)
- M Sattler
- Department of Adult Oncology, Dana-Farber Cancer Institute, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
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34
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Best D, Pasquet S, Littlewood TJ, Brunskill SJ, Pallister CJ, Watson SP. Platelet activation via the collagen receptor GPVI is not altered in platelets from chronic myeloid leukaemia patients despite the presence of the constitutively phosphorylated adapter protein CrkL. Br J Haematol 2001; 112:609-15. [PMID: 11260061 DOI: 10.1046/j.1365-2141.2001.02624.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
In this study, we show that the adapter proteins CrkL and Cbl undergo increases in tyrosine phosphorylation and form an intracellular complex in platelets stimulated with the snake venom toxin convulxin, a selective agonist at the collagen receptor glycoprotein VI (GPVI). Constitutive tyrosine phosphorylation of CrkL has previously been reported in platelets from chronic myeloid leukaemia (CML) patients. This was confirmed in the present study, and shown to result in a weak constitutive association of CrkL with Cbl and a number of other unidentified tyrosine-phosphorylated proteins. There was no further increase in phosphorylation of CrkL in CML platelets in response to GPVI activation, whereas phosphorylation of Cbl and its association with CrkL were potentiated. In addition, this was accompanied by a small increase in p42/ 44 mapkinase (MAPK) activity in CML platelets. The functional consequence of the presence of constitutively phosphorylated proteins in CML platelets was investigated by measurement of aminophospholipid exposure and alpha-granule secretion. This revealed little alteration in the concentration-response curves for either in CML platelets stimulated via GPVI, although maximal levels of P-selectin were depressed. Despite the minimal effect on platelet activation in CML patients, we cannot exclude a role for CrkL or Cbl in signal transduction pathways stimulated via GPVI.
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Affiliation(s)
- D Best
- Department of Pharmacology, University of Oxford, Mansfield, Oxford OX1 3QT, UK.
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35
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Tse KF, Mukherjee G, Small D. Constitutive activation of FLT3 stimulates multiple intracellular signal transducers and results in transformation. Leukemia 2000; 14:1766-76. [PMID: 11021752 DOI: 10.1038/sj.leu.2401905] [Citation(s) in RCA: 161] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Aberrant expression of FLT3 has been found in most cases of B-lineage ALL and AML, and subsets of T cell ALL, CML in blast crisis and CLL. In 20% of patients with AML the receptor has small internal tandem duplications of the juxtamembrane region which appear to contitutively activate the receptor. To investigate whether FLT3 activation could play a role in leukemia, we generated a constitutively activated FLT3 by fusing its cytoplasmic domain to the helix-loop-helix domain of TEL in analogy to the fusion that occurs with TEL-PDGFR in CMML. In vitro translation assays demonstrated oligomerization and intrinsic tyrosine kinase activity of the TEL-FLT3 chimeric receptor. Constitutively activated TEL-FLT3 conferred IL-3 independence and long-term proliferation to transfected Ba/F3 cells. Immunoblot analyses showed that JAK 2, STAT 3, STAT 5a, STAT 5b and CBL were tyrosine-phosphorylated in TEL-FLT3 expressing Ba/F3 cells in the absence of IL-3. These data suggest a possible role for the JAK/STAT pathway in FLT3 signaling. Transplantation of TEL-FLT3 expressing Ba/F3 cells into syngeneic mice caused mortality in all mice by 3 weeks after injection. Histopathologic analysis demonstrated a massive infiltration of mononuclear cells in the liver, spleen and bone marrow. The mimicking of naturally occurring TEL fusions provides an approach to assess aspects of the biology of activated FLT3, or other receptor-type tyrosine kinases (RTKs) in leukemic transformation.
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Affiliation(s)
- K F Tse
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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36
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Abstract
AbstractThe deregulated Bcr/Abl tyrosine kinase is responsible for the development of Philadelphia (Ph)-positive leukemia in humans. To investigate the significance of the C-terminal Abl actin-binding domain within Bcr/Abl p190 in the development of leukemia/lymphoma in vivo, mutant p190 DNA constructs were used to generate transgenic mice. Eight founder and progeny mice of 5 different lines were monitored for leukemogenesis. Latency was markedly increased and occurrence decreased in the p190 del C lines as compared with nonmutated p190BCR/ABL transgenics. Western blot analysis of involved hematologic tissues of the p190 del C transgenics with end-stage disease showed high-level expression of the transgene and tyrosine phosphorylation of Cbl and Hef1/Cas, proteins previously shown to be affected by Bcr/Abl. These results show that the actin-binding domain of Abl enhances leukemia development but does not appear to be an absolute requirement for leukemogenesis.
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37
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Abstract
The deregulated Bcr/Abl tyrosine kinase is responsible for the development of Philadelphia (Ph)-positive leukemia in humans. To investigate the significance of the C-terminal Abl actin-binding domain within Bcr/Abl p190 in the development of leukemia/lymphoma in vivo, mutant p190 DNA constructs were used to generate transgenic mice. Eight founder and progeny mice of 5 different lines were monitored for leukemogenesis. Latency was markedly increased and occurrence decreased in the p190 del C lines as compared with nonmutated p190BCR/ABL transgenics. Western blot analysis of involved hematologic tissues of the p190 del C transgenics with end-stage disease showed high-level expression of the transgene and tyrosine phosphorylation of Cbl and Hef1/Cas, proteins previously shown to be affected by Bcr/Abl. These results show that the actin-binding domain of Abl enhances leukemia development but does not appear to be an absolute requirement for leukemogenesis.
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38
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Imaizumi T, Araki K, Miura K, Araki M, Suzuki M, Terasaki H, Yamamura K. Mutant mice lacking Crk-II caused by the gene trap insertional mutagenesis: Crk-II is not essential for embryonic development. Biochem Biophys Res Commun 1999; 266:569-74. [PMID: 10600543 DOI: 10.1006/bbrc.1999.1869] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Crk family adapter proteins including Crk-II, Crk-I, and Crk-L consist mostly of SH2 and SH3 domains. Through the interactions between SH2 domain and phosphotyrosine residues and/or between SH3 domain and proline-rich motifs, they are involved in a variety of signaling cascades. Despite their essential roles in the signal transductions, knock-out mice of these molecules have not been reported yet. We performed the gene trap insertional mutagenesis with a trap vector, pU-Hachi, and generated a mutant mice line, Ayu 8104, in which the trap vector was inserted into the c-crk gene. Homozygous Ayu 8104 mice lacked Crk-II and Crk-I transcripts but expressed the truncated Crk proteins retaining one SH2 and one SH3 domain. Since the structure of the truncated proteins was similar to that of Crk-I, the insertion was considered to cause Crk-II-specific disruption. Homozygous mutant mice, however, did not exhibit any obvious abnormalities, suggesting that Crk-family adapters, Crk-II, Crk-I, and Crk-L would redundantly function in the signaling cascades and Crk-II was not apparently essential for embryonic development.
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Affiliation(s)
- T Imaizumi
- Institute of Molecular Embryology and Genetics, Kumamoto University School of Medicine, Kuhonji 4-24-1, Kumamoto, 862-0976, Japan
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39
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Affiliation(s)
- R Chopra
- Christie Hospital and Paterson Institute for Cancer Research, Manchester, UK
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40
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Fernández B, Czech MP, Meisner H. Role of protein kinase C in signal attenuation following T cell receptor engagement. J Biol Chem 1999; 274:20244-50. [PMID: 10400642 DOI: 10.1074/jbc.274.29.20244] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
T lymphocyte activation through stimulation of the T cell receptor complex and co-stimulatory receptors is associated with acute tyrosine phosphorylation of intracellular proteins, which in turn mediate downstream signaling events that regulate interleukin-2 expression and cell proliferation. The extent of protein tyrosine phosphorylation is rapidly attenuated after only 1-2 min of stimulation as a means of tightly controlling the initial signaling response. Here we show that this attenuation of tyrosine phosphorylation of Shc, CrkL, and the proto-oncogene Cbl is mimicked by treatment of mouse T lymphocytes or cultured Jurkat cells with phorbol 12-myristate 13-acetate. This effect is blocked by the specific protein kinase C inhibitor GF109203X, but not by PD98059, an inhibitor of MEK1/2 kinase. Activation of protein kinase C by phorbol ester also causes rapid (t(1)/(2) = 2 min) dissociation of both CrkL and p85/phosphoinositide 3-kinase from Cbl concomitant with Cbl tyrosine dephosphorylation. More important, GF109203X treatment of Jurkat cells prior to T cell receptor stimulation by anti-CD3/CD4 antibodies results in an enhanced (2-fold) peak of Cbl phosphorylation compared with that observed in control cells. Furthermore, the rate of attenuation of both Cbl tyrosine phosphorylation and its association with CrkL following stimulation with anti-CD3/CD4 antibodies is much slower in Jurkat cells treated with GF109203X. Taken together, these data provide strong evidence that one or more isoforms of phorbol ester-responsive protein kinase C play a key role in a feedback mechanism that attenuates tyrosine phosphorylation of proteins and reverses formation of signaling complexes in response to T cell receptor activation.
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Affiliation(s)
- B Fernández
- Program in Molecular Medicine and the Department of Biochemistry and Molecular Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA
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41
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Feshchenko EA, Shore SK, Tsygankov AY. Tyrosine phosphorylation of C-Cbl facilitates adhesion and spreading while suppressing anchorage-independent growth of V-Abl-transformed NIH3T3 fibroblasts. Oncogene 1999; 18:3703-15. [PMID: 10391678 DOI: 10.1038/sj.onc.1202672] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The protooncogenic protein c-Cbl becomes tyrosine phosphorylated in normal cells in response to a variety of external stimuli, as well as in cells transformed by oncogenic protein tyrosine kinases. Tyrosine phosphorylation of c-Cbl upregulates its binding to multiple crucial signaling molecules. However, the biological consequences of c-Cbl-mediated signaling are insufficiently understood. To analyse the biological functions of c-Cbl, we overexpressed wild-type c-Cbl and its tyrosine phosphorylation-defective mutant form in v-Abl-transformed NIH3T3 fibroblasts. In this system, wild-type c-Cbl facilitated adhesion and spreading of v-Abl-transformed fibroblasts on the extracellular matrix, while reducing anchorage independence of these cells, as measured by their colony-forming efficiency in soft agar. Therefore, overexpression of wild-type c-Cbl exhibits an overall transformation-suppressing effect. By contrast, overexpression of a tyrosine phosphorylation-defective form of c-Cbl increases neither adhesion nor anchorage dependence of v-Abl-transformed fibroblasts. Analysis of the role of individual tyrosine phosphorylation sites of c-Cbl in these phenomena indicates that both phosphatidylinositol-3' kinase and the CrkL adaptor protein may be involved in the observed effects of c-Cbl. To summarize, the results presented in this report indicate that c-Cbl is involved in regulation of cell adhesion and cytoskeletal rearrangements, and that these effects of c-Cbl are dependent on its tyrosine phosphorylation.
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Affiliation(s)
- E A Feshchenko
- Department of Microbiology and Immunology, Temple University School of Medicine, Philadelphia, Pennsylvania 19140, USA
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42
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Liu Y, Liu YC, Meller N, Giampa L, Elly C, Doyle M, Altman A. Protein Kinase C Activation Inhibits Tyrosine Phosphorylation of Cbl and Its Recruitment of Src Homology 2 Domain-Containing Proteins. THE JOURNAL OF IMMUNOLOGY 1999. [DOI: 10.4049/jimmunol.162.12.7095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Abstract
One of the major proteins that is rapidly tyrosine phosphorylated upon stimulation of the TCR/CD3 complex is the 120-kDa product of the c-cbl protooncogene (Cbl). Upon activation, tyrosine-phosphorylated Cbl interacts with the Src homology 2 (SH2) domains of several signaling proteins, e.g., phosphatidylinositol 3-kinase (PI3-K) and CrkL. In the present study, we report that pretreatment of Jurkat T cells with PMA reduced the anti-CD3-induced tyrosine phosphorylation of Cbl and, consequently, its activation-dependent association with PI3-K and CrkL. A specific protein kinase C (PKC) inhibitor (GF-109203X) reversed the effect of PMA on tyrosine phosphorylation of Cbl and restored the activation-dependent association of Cbl with PI3-K and CrkL. We also provide evidence that PKCα and PKCθ can physically associate with Cbl and are able to phosphorylate it in vitro and in vivo. Furthermore, a serine-rich motif at the C terminus of Cbl, which is critical for PMA-induced 14-3-3 binding, is also phosphorylated by PKCα and PKCθ in vitro. These results suggest that, by regulating tyrosine and serine phosphorylation of Cbl, PKC is able to control the association of Cbl with signaling intermediates, such as SH2 domain-containing proteins and 14-3-3 proteins, which may consequently result in the modulation of its function.
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Affiliation(s)
- Yuhong Liu
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology, San Diego, CA 92121
| | - Yun-Cai Liu
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology, San Diego, CA 92121
| | - Nahum Meller
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology, San Diego, CA 92121
| | - Leslie Giampa
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology, San Diego, CA 92121
| | - Chris Elly
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology, San Diego, CA 92121
| | - Melissa Doyle
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology, San Diego, CA 92121
| | - Amnon Altman
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology, San Diego, CA 92121
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Uemura N, Salgia R, Ewaniuk DS, Little MT, Griffin JD. Involvement of the adapter protein CRKL in integrin-mediated adhesion. Oncogene 1999; 18:3343-53. [PMID: 10362355 DOI: 10.1038/sj.onc.1202689] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
CRKL, an SH2-SH3-SH3 adapter protein, is one of the major tyrosine phosphoproteins detected in primary leukemic neutrophils from patients with CML. CRKL binds directly to BCR/ABL through its N-terminal SH3 domain, suggesting it may be involved in BCR/ABL signal transduction. However, the biological function of CRKL in either normal or leukemic cells is still largely unknown. In this study, we have examined the effects of overexpressing full length or deletion mutants of CRKL in hematopoietic cell lines. Full length, SH2- and SH3(N)-domain deletion mutants of CRKL were transfected into an interleukin-3-dependent hematopoietic cell line, Ba/F3, and 3-5 individual sublines which stably overexpressed each transgene were obtained [Ba/F-CRKL, Ba/F-CRKL deltaSH2, and Ba/F-CRKL deltaSH3(N)]. The growth properties of these transfected cells in the presence or absence of IL-3 were not different from mock transfected or untransfected Ba/F3 cells. However, Ba/F3 cells overexpressing full length CRKL, but not deletion mutants of CRKL, were found to have an increase in their ability to bind to fibronectin-coated surfaces. Further, expression of full length, but not deltaSH2- or deltaSH3-CRKL deletion mutants, was found to alter cell morphology on fibronectin-coated plates, an effect which was further enhanced by certain kinds of stress stimuli, such as ionizing radiation. Similar results were obtained when CRKL was transiently overexpressed in Ba/F3 cells, and were also obtained in a second IL-3 dependent hematopoietic cell line, 32Dcl3. Adhesion to fibronectin was blocked by anti-beta1 integrin monoclonal antibody, but overexpression of CRKL did not affect surface expression of beta1 integrins, nor did it spontaneously induce expression of the beta1 integrin 'activation' epitope recognized by the 9EG7 monoclonal antibody. These data suggest a role for CRKL in signaling pathways which regulate adhesion to fibronectin.
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Affiliation(s)
- N Uemura
- Department of Adult Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts 02115, USA
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44
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CrkL Activates Integrin-Mediated Hematopoietic Cell Adhesion Through the Guanine Nucleotide Exchange Factor C3G. Blood 1999. [DOI: 10.1182/blood.v93.11.3713] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
AbstractCrkL is a member of the Crk family of adapter proteins consisting mostly of SH2 and SH3 domains. CrkL is most abundantly expressed in hematopoietic cells and has been implicated in pathogenesis of chronic myelogenous leukemia. However, its function has not been precisely defined. Here, we show that overexpression of CrkL enhances the adhesion of hematopoietic 32D cells to fibronectin. The CrkL-induced increase in cell adhesion was blocked by antibodies against VLA-4 (4β1) and VLA-5 (5β1) but was observed without changes in surface expression levels of these integrins. Studies using CrkL mutants demonstrated that the SH2 domain is partially required for enhancing cell adhesion, whereas the C-terminal SH3 domain as well as the tyrosine phosphorylation site (Y207) is dispensable. In contrast, the N-terminal SH3 domain, involved in binding C3G and other signaling molecules, was showed to play a crucial role, because a mutant defective of this domain showed an inhibitory effect on the cell adhesion to fibronectin. Furthermore, overexpression of C3G also increased the adhesion of hematopoietic cells to fibronectin, whereas a C3G mutant lacking the guanine nucleotide exchange domain abrogated the CrkL-induced increase in cell adhesion. On the other hand, a dominant negative mutant of H-Ras or that of Raf-1 enhanced the basal and CrkL-induced cell adhesion and that of R-Ras modestly decreased the adhesion. Taken together, these results indicate that the CrkL-C3G complex activates VLA-4 and VLA-5 in hematopoietic cells, possibly by activating the small GTP binding proteins, including R-Ras, through the guanine nucleotide exchange activity of C3G.
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45
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Abstract
CrkL is a member of the Crk family of adapter proteins consisting mostly of SH2 and SH3 domains. CrkL is most abundantly expressed in hematopoietic cells and has been implicated in pathogenesis of chronic myelogenous leukemia. However, its function has not been precisely defined. Here, we show that overexpression of CrkL enhances the adhesion of hematopoietic 32D cells to fibronectin. The CrkL-induced increase in cell adhesion was blocked by antibodies against VLA-4 (4β1) and VLA-5 (5β1) but was observed without changes in surface expression levels of these integrins. Studies using CrkL mutants demonstrated that the SH2 domain is partially required for enhancing cell adhesion, whereas the C-terminal SH3 domain as well as the tyrosine phosphorylation site (Y207) is dispensable. In contrast, the N-terminal SH3 domain, involved in binding C3G and other signaling molecules, was showed to play a crucial role, because a mutant defective of this domain showed an inhibitory effect on the cell adhesion to fibronectin. Furthermore, overexpression of C3G also increased the adhesion of hematopoietic cells to fibronectin, whereas a C3G mutant lacking the guanine nucleotide exchange domain abrogated the CrkL-induced increase in cell adhesion. On the other hand, a dominant negative mutant of H-Ras or that of Raf-1 enhanced the basal and CrkL-induced cell adhesion and that of R-Ras modestly decreased the adhesion. Taken together, these results indicate that the CrkL-C3G complex activates VLA-4 and VLA-5 in hematopoietic cells, possibly by activating the small GTP binding proteins, including R-Ras, through the guanine nucleotide exchange activity of C3G.
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46
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Galletta BJ, Niu XP, Erickson MR, Abmayr SM. Identification of a Drosophila homologue to vertebrate Crk by interaction with MBC. Gene X 1999; 228:243-52. [PMID: 10072777 DOI: 10.1016/s0378-1119(99)00010-4] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The vertebrate adapter protein termed Crk was initially identified from the chicken CT10 retrovirus on the basis of its transforming activity (Mayer et al., 1988. Nature 332, 272-275). We have identified a Drosophila protein with homology to vertebrate Crk, termed dCRK, by interaction with the protein encoded by the Drosophila myoblast city (mbc) gene. The dCRK protein has extensive homology to the both the Crk-II form of vertebrate Crk and the Crk-related protein CRKL, and includes one SH2 domain followed by two SH3 domains. A single protein of approx. 37kDa is detected in extracts from embryos, and Northern analysis revealed a single transcript of 1.3kb. The dCrk mRNA is abundant throughout embryogenesis, declines during the larval stages, and reappears during pupation. In addition, maternally-provided transcripts have been detected. During embryogenesis, the spatial distribution of this transcript is relatively broad and appears to include all germ layers. Finally, dCrk is located on the fourth chromosome, approximately at cytological position 101F-102A.
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MESH Headings
- Adaptor Proteins, Signal Transducing
- Amino Acid Sequence
- Animals
- Blotting, Western
- Chromosome Mapping
- Cytoskeletal Proteins
- DNA, Complementary/chemistry
- DNA, Complementary/genetics
- DNA, Complementary/isolation & purification
- Drosophila/chemistry
- Drosophila/embryology
- Drosophila/genetics
- Drosophila Proteins
- Embryo, Nonmammalian/metabolism
- Embryonic Development
- Gene Expression Regulation, Developmental
- Insect Proteins/metabolism
- Molecular Sequence Data
- Nuclear Proteins/genetics
- Protein Kinases/genetics
- Proto-Oncogene Proteins/genetics
- Proto-Oncogene Proteins/metabolism
- Proto-Oncogene Proteins c-crk
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Sequence Analysis, DNA
- Sequence Homology, Amino Acid
- Tissue Distribution
- Vertebrates/genetics
- src Homology Domains/genetics
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Affiliation(s)
- B J Galletta
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
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Kolibaba KS, Bhat A, Heaney C, Oda T, Druker BJ. CRKL binding to BCR-ABL and BCR-ABL transformation. Leuk Lymphoma 1999; 33:119-26. [PMID: 10194128 DOI: 10.3109/10428199909093732] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The SH2-SH3 domain-containing adaptor protein CRKL is the predominant tyrosine phosphorylated protein in chronic myelogenous leukemia (CML) neutrophils and BCR-ABL-expressing cell lines. The amino terminal CRKL SH3 domain binds directly to a proline-rich region in the C-terminus of BCR-ABL. BCR-ABL mutants with deletions of this region were constructed to assess biologic effects of eliminating the CRKL binding site. Yeast two-hybrid analysis and gel overlay assays show eradication of the direct interaction of CRKL with BCR-ABL in the proline deletion mutants. However, these BCR-ABL mutants transform myeloid cells to growth factor independence, and in these cells CRKL is tyrosine phosphorylated and associates with BCR-ABL. These findings suggest both direct and indirect interactions of CRKL with BCR-ABL. Thus, disruption of the direct interaction with BCR-ABL has not excluded a role for CRKL in BCR-ABL-mediated transformation.
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Affiliation(s)
- K S Kolibaba
- Division of Hematology and Medical Oncology, Oregon Health Sciences University, Portland 97201, USA
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Zhang Z, Elly C, Altman A, Liu YC. Dual regulation of T cell receptor-mediated signaling by oncogenic Cbl mutant 70Z. J Biol Chem 1999; 274:4883-9. [PMID: 9988730 DOI: 10.1074/jbc.274.8.4883] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We previously showed that an oncogenic Cbl mutant (70Z) is constitutively active in transcriptional activation of nuclear factor at activated T cells (NFAT). However, the mechanism underlying this effect remains unclear. Here we analyzed the effects of 70Z mutations at an amino-terminal loss of function site (Gly-306) and at carboxyl-terminal potential tyrosine or serine phosphorylation sites on association with signaling proteins and on NFAT activation. Mutation at Gly-306 of 70Z disrupted its association with Zap-70 and almost completely abolished its ability to induce NFAT activation under basal and ionomycin-stimulated conditions. However, mutations at potential tyrosine or serine phosphorylation sites had little effect. In fact, expression of 70Z with Tyr-700, Tyr-731, or Tyr-774 mutated to Phe increased NFAT activity in comparison with unmutated 70Z. These findings suggest that an amino terminus-mediated interaction of 70Z with Zap-70 plays a positive role and that a carboxyl terminus-mediated, phosphotyrosine-dependent interaction with their binding proteins plays a negative role in 70Z-mediated NFAT activation. In support of this notion are the observations that 70Z reduced T cell receptor-induced NFAT activation and that wild-type Cbl further inhibited this event, suggesting that both 70Z and wild-type Cbl employ a similar mechanism by which Cbl proteins dually regulate T cell receptor-mediated signaling.
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Affiliation(s)
- Z Zhang
- Division of Cell Biology, La Jolla Institute for Allergy and Immunology, San Diego, California 92121, USA
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van Leeuwen JE, Paik PK, Samelson LE. Activation of nuclear factor of activated T cells-(NFAT) and activating protein 1 (AP-1) by oncogenic 70Z Cbl requires an intact phosphotyrosine binding domain but not Crk(L) or p85 phosphatidylinositol 3-kinase association. J Biol Chem 1999; 274:5153-62. [PMID: 9988765 DOI: 10.1074/jbc.274.8.5153] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The Cbl proto-oncogene product is a complex adapter protein that functions as a negative regulator of protein tyrosine kinases. It is rapidly tyrosine-phosphorylated and associates with Crk(L) and p85 phosphatidylinositol 3-kinase (PI3K) upon engagement of numerous receptors linked to tyrosine kinases. Elucidation of the mechanism(s) underlying Cbl deregulation is therefore of considerable interest. The 70Z Cbl oncoprotein shows increased baseline tyrosine phosphorylation in fibroblasts and enhances nuclear factor of activated T cells (NFAT) activity in Jurkat T cells. Its transforming ability has been proposed to relate to its increased phosphotyrosine content. We demonstrate that 70Z Cbl shows increased basal and activation-induced tyrosine phosphorylation and association with Crk(L) and p85 PI3K in Jurkat T cells. 70Z Cbl, however, retains the ability to enhance NFAT and activating protein 1 (AP1) activity in the absence of Crk(L)/p85 PI3K association. In contrast, the G306E mutation, which inactivates the phosphotyrosine binding domain of Cbl, blocks NFAT/AP1 activation by 70Z Cbl. We conclude that 70Z Cbl-induced NFAT/AP1 activation requires the phosphotyrosine binding domain but not Crk(L)/p85 PI3K association. We hypothesize that 70Z Cbl acts as a dominant negative by blocking the negative regulatory function of the Cbl phosphotyrosine binding domain on protein-tyrosine kinases.
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Affiliation(s)
- J E van Leeuwen
- Cell Biology and Metabolism Branch, NICHD, National Institutes of Health, Bethesda, Maryland 20892, USA.
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Wang Y, Yeung YG, Stanley ER. CSF-1 stimulated multiubiquitination of the CSF-1 receptor and of Cbl follows their tyrosine phosphorylation and association with other signaling proteins. J Cell Biochem 1999. [DOI: 10.1002/(sici)1097-4644(19990101)72:1<119::aid-jcb13>3.0.co;2-r] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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