Dataset Information

?-tubulin K40 acetylation is required for contact inhibition of proliferation and cell-substrate adhesion.

ABSTRACT: Acetylation of ?-tubulin on lysine 40 marks long-lived microtubules in structures such as axons and cilia, and yet the physiological role of ?-tubulin K40 acetylation is elusive. Although genetic ablation of the ?-tubulin K40 acetyltransferase ?Tat1 in mice did not lead to detectable phenotypes in the developing animals, contact inhibition of proliferation and cell-substrate adhesion were significantly compromised in cultured ?Tat1(-/-) fibroblasts. First, ?Tat1(-/-) fibroblasts kept proliferating beyond the confluent monolayer stage. Congruently, ?Tat1(-/-) cells failed to activate Hippo signaling in response to increased cell density, and the microtubule association of the Hippo regulator Merlin was disrupted. Second, ?Tat1(-/-) cells contained very few focal adhesions, and their ability to adhere to growth surfaces was greatly impaired. Whereas the catalytic activity of ?TAT1 was dispensable for monolayer formation, it was necessary for cell adhesion and restrained cell proliferation and activation of the Hippo pathway at elevated cell density. Because ?-tubulin K40 acetylation is largely eliminated by deletion of ?TAT1, we propose that acetylated microtubules regulate contact inhibition of proliferation through the Hippo pathway.

SUBMITTER: Aguilar A

PROVIDER: S-EPMC4055265 | biostudies-literature | 2014 Jun

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Α-tubulin K40 acetylation is required for contact inhibition of proliferation and cell-substrate adhesion.

Aguilar Andrea A Becker Lars L Tedeschi Thomas T Heller Stefan S Iomini Carlo C Nachury Maxence V MV

Molecular biology of the cell 20140417 12

Acetylation of α-tubulin on lysine 40 marks long-lived microtubules in structures such as axons and cilia, and yet the physiological role of α-tubulin K40 acetylation is elusive. Although genetic ablation of the α-tubulin K40 acetyltransferase αTat1 in mice did not lead to detectable phenotypes in the developing animals, contact inhibition of proliferation and cell-substrate adhesion were significantly compromised in cultured αTat1(-/-) fibroblasts. First, αTat1(-/-) fibroblasts kept proliferati ...[more]

PMID: 24743598

Similar Datasets

Project description:BackgroundThe leading cause of cancer-related mortality worldwide is lung cancer, and its clinical outcome and prognosis are still unsatisfactory. The understanding of potential molecular targets is necessary for clinical implications in precision diagnostic and/or therapeutic purposes. Histone deacetylase 6 (HDAC6), a major deacetylase enzyme, is a promising target for cancer therapy; however, the molecular mechanism regulating cancer pathogenesis is largely unknown.MethodsThe clinical relevance of HDAC6 expression levels and their correlation with the overall survival rate were analyzed based on the TCGA and GEO databases. HDAC6 expression in clinical samples obtained from lung cancer tissues and patient-derived primary lung cancer cells was evaluated using qRT-PCR and Western blot analysis. The potential regulatory mechanism of HDAC6 was identified by proteomic analysis and validated by immunoblotting, immunofluorescence, microtubule sedimentation, and immunoprecipitation-mass spectrometry (IP-MS) assays using a specific inhibitor of HDAC6, trichostatin A (TSA) and RNA interference to HDAC6 (siHDAC6). Lung cancer cell growth was assessed by an in vitro 2-dimensional (2D) cell proliferation assay and 3D tumor spheroid formation using patient-derived lung cancer cells.ResultsHDAC6 was upregulated in lung cancer specimens and significantly correlated with poor prognosis. Inhibition of HDAC6 by TSA and siHDAC6 caused downregulation of phosphorylated extracellular signal-regulated kinase (p-ERK), which was dependent on the tubulin acetylation status. Tubulin acetylation induced by TSA and siHDAC6 mediated the dissociation of p-ERK on microtubules, causing p-ERK destabilization. The proteomic analysis demonstrated that the molecular chaperone glucose-regulated protein 78 (GRP78) was an important scaffolder required for p-ERK localization on microtubules, and this phenomenon was significantly inhibited by either TSA, siHDAC6, or siGRP78. In addition, suppression of HDAC6 strongly attenuated an in vitro 2D lung cancer cell growth and an in vitro 3D patient derived-lung cancer spheroid growth.ConclusionsHDAC6 inhibition led to upregulate tubulin acetylation, causing GRP78-p-ERK dissociation from microtubules. As a result, p-ERK levels were decreased, and lung cancer cell growth was subsequently suppressed. This study reveals the intriguing role and molecular mechanism of HDAC6 as a tumor promoter, and its inhibition represents a promising approach for anticancer therapy.

Dataset Information

?-tubulin K40 acetylation is required for contact inhibition of proliferation and cell-substrate adhesion.

Publications

Α-tubulin K40 acetylation is required for contact inhibition of proliferation and cell-substrate adhesion.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets