4 research outputs found
Proteomic Dissection of the von Hippel–Lindau (VHL) Interactome
The <i>von Hippel–Lindau</i> (<i>VHL</i>) tumor suppressor gene encodes a component of a ubiquitin ligase complex containing elongin B, elongin C, cullin 2, and Rbx1, which acts as a negative regulator of hypoxia inducible factor (HIF). VHL ubiquitinates and degrades the alpha subunits of HIF, and this is proposed to suppress tumorigenesis and tumor angiogenesis. Several lines of evidence also suggest important roles for HIF-independent VHL functions in the maintenance of primary cilium, extracellular matrix formation, and tumor suppression. We undertook a series of proteomic analyses to gain a comprehensive picture of the VHL-interacting proteins. We found that the ARF tumor suppressor interacts with VHL30, a longer VHL isoform, but not with VHL19, a shorter VHL isoform. ARF was found to release VHL30 from the E3 ligase complex, promoting the binding of VHL30 to a protein arginine methyltransferase, PRMT3. Our analysis of the VHL19 interactome also uncovered that VHL19 displays an affinity to collagens and their biosynthesis enzymes
Proteomic Analysis of the EWS-Fli‑1 Interactome Reveals the Role of the Lysosome in EWS-Fli‑1 Turnover
Ewing
sarcoma is a cancer of bone and soft tissue in children that
is characterized by a chromosomal translocation involving EWS and
an Ets family transcription factor, most commonly Fli-1. EWS-Fli-1
fusion accounts for 85% of cases. The growth and survival of Ewing
sarcoma cells are critically dependent on EWS-Fli-1. A large body
of evidence has established that EWS-Fli-1 functions as a DNA-binding
transcription factor that regulates the expression of a number of
genes important for cell proliferation and transformation. However,
little is known about the biochemical properties of the EWS-Fli-1
protein. We undertook a series of proteomic analyses to dissect the
EWS-Fli-1 interactome. Employing a proximity-dependent biotinylation
technique, BioID, we identified cation-independent mannose 6-phosphate
receptor (CIMPR) as a protein located in the vicinity of EWS-Fli-1
within a cell. CIMPR is a cargo that mediates the delivery of lysosomal
hydrolases from the trans-Golgi network to the endosome, which are
subsequently transferred to the lysosomes. Further molecular cell
biological analyses uncovered a role for lysosomes in the turnover
of the EWS-Fli-1 protein. We demonstrate that an mTORC1 active-site
inhibitor, torin 1, which stimulates the TFEB-lysosome pathway, can
induce the degradation of EWS-Fli-1, suggesting a potential therapeutic
approach to target EWS-Fli-1 for degradation
Proteomic Analysis of the EWS-Fli‑1 Interactome Reveals the Role of the Lysosome in EWS-Fli‑1 Turnover
Ewing
sarcoma is a cancer of bone and soft tissue in children that
is characterized by a chromosomal translocation involving EWS and
an Ets family transcription factor, most commonly Fli-1. EWS-Fli-1
fusion accounts for 85% of cases. The growth and survival of Ewing
sarcoma cells are critically dependent on EWS-Fli-1. A large body
of evidence has established that EWS-Fli-1 functions as a DNA-binding
transcription factor that regulates the expression of a number of
genes important for cell proliferation and transformation. However,
little is known about the biochemical properties of the EWS-Fli-1
protein. We undertook a series of proteomic analyses to dissect the
EWS-Fli-1 interactome. Employing a proximity-dependent biotinylation
technique, BioID, we identified cation-independent mannose 6-phosphate
receptor (CIMPR) as a protein located in the vicinity of EWS-Fli-1
within a cell. CIMPR is a cargo that mediates the delivery of lysosomal
hydrolases from the trans-Golgi network to the endosome, which are
subsequently transferred to the lysosomes. Further molecular cell
biological analyses uncovered a role for lysosomes in the turnover
of the EWS-Fli-1 protein. We demonstrate that an mTORC1 active-site
inhibitor, torin 1, which stimulates the TFEB-lysosome pathway, can
induce the degradation of EWS-Fli-1, suggesting a potential therapeutic
approach to target EWS-Fli-1 for degradation
Cumulative number of distinct peptides as a function of the addition of more good spectra (identified with ≥ 0
<p><b>Copyright information:</b></p><p>Taken from "Integration with the human genome of peptide sequences obtained by high-throughput mass spectrometry"</p><p>Genome Biology 2004;6(1):R9-R9.</p><p>Published online 10 Dec 2004</p><p>PMCID:PMC549070.</p><p>Copyright © 2004 Desiere et al.; licensee BioMed Central Ltd.</p>9). Eventually the pattern is expected to show saturation, as most observable peptides will have been cataloged. However, at present there is no evidence of saturation and around 100 new peptides are still cataloged per 1,000 identified spectra added