Endogenous androgen receptor proteomic profiling reveals genomic subcomplex involved in prostate tumorigenesis.

Androgen receptor (AR) is a key player in prostate cancer development and progression. Here we applied immunoprecipitation mass spectrometry of endogenous AR in LNCaP cells to identify components of the AR transcriptional complex. In total, 66 known and novel AR interactors were identified in the presence of synthetic androgen, most of which were critical for AR-driven prostate cancer cell proliferation. A subset of AR interactors required for LNCaP proliferation were profiled using chromatin immunoprecipitation assays followed by sequencing, identifying distinct genomic subcomplexes of AR interaction partners. Interestingly, three major subgroups of genomic subcomplexes were identified, where selective gain of function for AR genomic action in tumorigenesis was found, dictated by FOXA1 and HOXB13. In summary, by combining proteomic and genomic approaches we reveal subclasses of AR transcriptional complexes, differentiating normal AR behavior from the oncogenic state. In this process, the expression of AR interactors has key roles by reprogramming the AR cistrome and interactome in a genomic location-specific manner.

The atheroma plaque secretome stimulates the mobilization of endothelial progenitor cells ex vivo.

Endothelial progenitor cells (EPCs) constitute a promising alternative in cardiovascular regenerative medicine due to their assigned role in angiogenesis and vascular repair. In response to injury, EPCs promote vascular remodeling by replacement of damaged endothelial cells and/or by secreting angiogenic factors over the damaged tissue. Nevertheless, such mechanisms need to be further characterized. In the current approach we have evaluated the initial response of early EPCs (eEPCs) from healthy individuals after direct contact with the factors released by carotid arteries complicated with atherosclerotic plaques (AP), in order to understand the mechanisms underlying the neovascularization and remodeling properties assigned to these cells. Herein, we found that the AP secretome stimulated eEPCs proliferation and mobilization ex vivo, and such increase was accompanied by augmented permeability, cell contraction and also an increase of cell-cell adhesion in association with raised vinculin levels. Furthermore, a comparative mass spectrometry analysis of control versus stimulated eEPCs revealed a differential expression of proteins in the AP treated cells, mostly involved in cell migration, proliferation and vascular remodeling. Some of these protein changes were also detected in the eEPCs isolated from atherosclerotic patients compared to eEPCs from healthy donors. We have shown, for the first time, that the AP released factors activate eEPCs ex vivo by inducing their mobilization together with the expression of vasculogenic related markers. The present approach could be taken as a ex vivo model to study the initial activation of vascular cells in atherosclerosis and also to evaluate strategies looking to potentiate the mobilization of EPCs prior to clinical applications.

Differential proteomics reveals the hallmarks of seed development in common bean (Phaseolus vulgaris L.).

UNLABELLED: Common bean (Phaseolus vulgaris L.) is one of the most consumed staple foods worldwide. Little is known about the molecular mechanisms controlling seed development. This study aims to comprehensively describe proteome dynamics during seed development of common bean. A high-throughput gel-free proteomics approach (LC-MS/MS) was conducted on seeds at 10, 20, 30 and 40days after anthesis, spanning from late embryogenesis until desiccation. Of the 418 differentially accumulated proteins identified, 255 were characterized, most belonging to protein metabolism. An accumulation of proteins belonging to the MapMan functional categories of "protein", "glycolysis", "TCA", "DNA", "RNA", "cell" and "stress" were found at early seed development stages, reflecting an extensive metabolic activity. In the mid stages, accumulation of storage, signaling, starch synthesis and cell wall-related proteins stood out. In the later stages, an increase in proteins related to redox, protein degradation/modification/folding and nucleic acid metabolisms reflect that seed desiccation-resistance mechanisms were activated. Our study unveils new clues to understand the regulation of seed development mediated by post-translational modifications and maintenance of genome integrity. This knowledge enhances the understanding on seed development molecular mechanisms that may be used in the design and selection of common bean seeds with desired quality traits. SIGNIFICANCE: Common bean (P. vulgaris) is an important source of proteins and carbohydrates worldwide. Despite the agronomic and economic importance of this pulse, knowledge on common bean seed development is limited. Herein, a gel-free high throughput methodology was used to describe the proteome changes during P. vulgaris seed development. Data obtained will enhance the knowledge on the molecular mechanisms controlling this grain legume seed development and may be used in the design and selection of common bean seeds with desired quality traits. Results may be extrapolated to other pulses.

Determination of polycyclic aromatic hydrocarbons and polycylic aromatic sulfur heterocycles by high-performance liquid chromatography with fluorescence and atmospheric pressure chemical ionization mass spectrometry detection in seawater and sediment samples.

Two methods for determining 10 polycyclic aromatic compounds were developed. Both methods were based on high-performance liquid chromatography (HPLC), but one method used fluorescence detection, while the other used atmospheric pressure chemical ionization mass spectrometry (APCI-MS). For water analysis, solid-phase extraction (SPE) was on-line coupled to the separation system. Using a styrene-divinylbenzene copolymer (PLRP-s) as sorbent in the SPE and adding 20% of acetonitrile to the water sample before its preconcentration, recoveries were above 70% for most of the compounds. For the fluorescence method, all compounds were detected and six of them could be quantified at concentrations higher than 0.02 microg 1(-1). For the MS detection method, only seven of the compounds were detected and six were quantified at concentrations higher than 0.06 microg 1(-1). To analyse sediment samples, an extraction with dichloromethane was used and, due to the complexity of the matrix, a standard addition calibration was carried out. Seawater and sediment samples taken from the Tarragona fishing port and marina on the coast of Catalonia (Spain) were analysed, and five compounds (benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, benzo[ghi]perylene and indeno[1,2,3-cd]pyrene) were quantified in the sediment samples.