PTK2 and PTPN11 expression in myelodysplastic syndromes

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)OBJECTIVE: The aim of this study was to evaluate the expression of protein tyrosine kinase 2 and protein tyrosine phosphatase non-receptor type 11, which respectively encode focal adhesion kinase protein and src homology 2 domain-containing protein-tyrosine phosphatase 2, in hematopoietic cells from patients with myelodysplastic syndromes. METHODS: Protein tyrosine kinase 2 and tyrosine phosphatase non-receptor type 11 expressions were analyzed by quantitative polymerase chain reaction in bone marrow cells from patients with myelodysplastic syndromes and healthy donors. RESULTS: Protein tyrosine kinase 2 and tyrosine phosphatase non-receptor type 11 expressions did not significantly differ between normal cells and myelodysplastic cells. CONCLUSIONS: Our data suggest that despite the relevance of focal adhesion kinase and src homology 2 domaincontaining protein-tyrosine phosphatase 2 in hematopoietic disorders, their mRNA expression do not significantly differ between total bone marrow cells from patients with myelodysplastic syndromes and healthy donors.681013711375Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

ARHGAP21 associates with FAK and PKC zeta and is redistributed after cardiac pressure overload

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)ARHGAP21 is highly expressed in the heart, which demonstrates activity over Cdc42 and interacts with proteins of the cytoskeleton and adherent junctions. The main cause of cardiac hypertrophy is mechanical stimulus; therefore we analyzed ARHGAP21 expression after acute mechanical stress in the myocardium and its association with FAK and PKC zeta. We demonstrated that ARHGAP21 is relocated to Z-lines and costameres after pressure overload, and interacts with PKC zeta and FAK in control rats (sham), rats submitted to aortic clamping and spontaneously hypertensive rats (SHR). Co-transfection using ARHGAP21 and PKC zeta constructions demonstrated that ARHGAP21 associates with PKC zeta-GST and endogenous FAK. Pull-down assay showed that ARHGAP21 binds to the C-terminal region of FAK. Moreover, ARHGAP21 binds to PKC zeta phosphorylated on Thr410 in sham and SHR. However, ARHGAP21 only binds to FAK phosphorylated on Tyr925 of SHR. Additionally, PKC zeta is phosphorylated by mechanical stimuli. These results suggest that ARHGAP21 may act as a signaling or scaffold protein of FAK and PKC zeta signaling pathways, developing an important function during cardiac stress. (c) 2008 Elsevier Inc. All rights reserved.3744641646Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

The CATS (FAM64A) protein is a substrate of the Kinase Interacting Stathmin (KIS)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The CATS protein (also known as FAM64A and RCS1) was first identified as a novel CALM (PICALM) interactor that influences the subcellular localization of the leukemogenic fusion protein CALM/AF10. CATS is highly expressed in cancer cell lines in a cell cycle dependent manner and is induced by mitogens. CATS is considered a marker for proliferation, known to control the metaphase-to-anaphase transition during the cell division. Using CATS as a bait in a yeast two-hybrid screen we identified the Kinase Interacting Stathmin (MS or UHMK1) protein as a CATS interacting partner. The interaction between CATS and KIS was confirmed by GST pull-down, co-immunopreciptation and co-localization experiments. Using kinase assay we showed that CATS is a substrate of KIS and mapped the phosphorylation site to CATS serine 131 (S131). Protein expression analysis revealed that KIS levels changed in a cell cycle-dependent manner and in the opposite direction to CATS levels. In a reporter gene assay KIS was able to enhance the transcriptional repressor activity of CATS, independent of CATS phophorylation at S131. Moreover, we showed that CATS and KIS antagonize the transactivation capacity of CALM/AF10.In summary, our results show that CATS interacts with and is a substrate for KIS, suggesting that KIS regulates CATS function. (c) 2013 Elsevier B.V. All rights reserved.1833512691279Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Deutsche Krebshilfe [109031]Deutsche Forschungsgemeinschaft [SFB 684 A6, BO 938/4-1]Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)FAPESP [07/08019-1, 07/54870-5]CNPq [101624/2011-5]Deutsche Krebshilfe [109031]Deutsche Forschungsgemeinschaft [SFB 684 A6, BO 938/4-1

ARHGAP21 Protein, a New Partner of alpha-Tubulin Involved in Cell-Cell Adhesion Formation and Essential for Epithelial-Mesenchymal Transition

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Cell-cell adhesions and the cytoskeletons play important and coordinated roles in cell biology, including cell differentiation, development, and migration. Adhesion and cytoskeletal dynamics are regulated by Rho-GTPases. ARHGAP21 is a negative regulator of Rho-GTPases, particularly Cdc42. Here we assess the function ofARHGAP21in cell-cell adhesion, cell migration, and scattering. We find that ARHGAP21 is localized in the nucleus, cytoplasm, or perinuclear region but is transiently redistributed to cell-cell junctions 4 h after initiation of cell-cell adhesion. ARHGAP21 interacts with Cdc42, and decreased Cdc42 activity coincides with the appearance of ARHGAP21 at the cell-cell junctions. Cells lacking ARHGAP21 expression show weaker cell-cell adhesions, increased cell migration, and a diminished ability to undergo hepatocyte growth factor-induced epithelial-mesenchymal transition (EMT). In addition, ARHGAP21 interacts with alpha-tubulin, and it is essential for alpha-tubulin acetylation in EMT. Our findings indicate that ARHGAP21 is a Rho-GAP involved in cell-cell junction remodeling and that ARHGAP21 affects migration and EMT through alpha-tubulin interaction and acetylation.288421792189Instituto Nacional de Ciencia e Tecnologia do Sangue (INCT)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Brigham Young University Cancer Research CenterFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq