Publications by authors named "Sofia Dimou"

Most transmembrane membrane proteins are thought to traffic to the plasma membrane (PM) via the conventional secretory pathway through sorting from the Golgi. However, our recent work has shown that in the filamentous fungus Aspergillus nidulans several nutrient transporters and other major membrane proteins traffic to the PM via Golgi-bypass and independently of known post-Golgi secretory mechanisms. Here in an effort to dissect the molecular mechanism underlying membrane cargo trafficking via Golgi-bypass we design and use unbiased genetic screens, based on the UapA uric acid-xanthine transporter, which allowed the isolation of mutants defective in UapA translocation to the plasma membrane.

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Membrane proteins are sorted to the plasma membrane via Golgi-dependent trafficking. However, our recent studies challenged the essentiality of Golgi in the biogenesis of specific transporters. Here, we investigate the trafficking mechanisms of membrane proteins by following the localization of the polarized R-SNARE SynA versus the non-polarized transporter UapA, synchronously co-expressed in wild-type or isogenic genetic backgrounds repressible for conventional cargo secretion.

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Neosynthesized plasma membrane (PM) proteins co-translationally translocate to the ER, concentrate at regions called ER-exit sites (ERes) and pack into COPII secretory vesicles which are sorted to the early-Golgi through membrane fusion. Following Golgi maturation, membrane cargoes reach the late-Golgi, from where they exit in clathrin-coated vesicles destined to the PM, directly or through endosomes. Post-Golgi membrane cargo trafficking also involves the cytoskeleton and the exocyst.

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The purpose of this study was to describe the demographic and clinical features of the inpatients currently residing at the Psychiatric Hospital of Leros. The present systematic documentation and presentation aimed to demonstrate the standard of living and healthcare conditions provided today, after the implementation of the State's "Psychargos" program; this is the main Greek Psychiatric reform program, adhering to the principles of deinstitutionalization and community psychiatry, in accordance with the current international guidelines. In addition, we discussed the current relationship between the psychiatric departments of the hospital and the other departments and clinics in terms of providing healthcare services to chronic psychiatric inpatients in full compliance with the biopsychosocial model and its application to the unique case of Leros.

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Nutrient transporters have been shown to translocate to the plasma membrane (PM) of the filamentous fungus an unconventional trafficking route that bypasses the Golgi. This finding strongly suggests the existence of distinct COPII vesicle subpopulations, one following Golgi-dependent conventional secretion and the other directed towards the PM. Here, we address whether Golgi-bypass concerns cargoes other than nutrient transporters and whether Golgi-bypass is related to cargo structure, size, abundance, physiological function, or polar vs.

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Solute and ion transporters are proteins essential for cell nutrition, detoxification, signaling, homeostasis and drug resistance. Being polytopic transmembrane proteins, they are co-translationally inserted and folded into the endoplasmic reticulum (ER) of eukaryotic cells and subsequently sorted to their final membrane destination via vesicular secretion. During their trafficking and in response to physiological/stress signals or prolonged activity, transporters undergo multiple quality control processes and regulated turnover.

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Eukaryotic plasma membrane (PM) transporters face critical challenges that are not widely present in prokaryotes. The two most important issues are proper subcellular traffic and targeting to the PM, and regulated endocytosis in response to physiological, developmental, or stress signals. Sorting of transporters from their site of synthesis, the endoplasmic reticulum (ER), to the PM has been long thought, but not formally shown, to occur via the conventional Golgi-dependent vesicular secretory pathway.

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Nutrient transporters, being polytopic membrane proteins, are believed, but not formally shown, to traffic from their site of synthesis, the ER, to the plasma membrane through Golgi-dependent vesicular trafficking. Here, we develop a novel genetic system to investigate the trafficking of a neosynthesized model transporter, the well-studied UapA purine transporter of Aspergillus nidulans. We show that sorting of neosynthesized UapA to the plasma membrane (PM) bypasses the Golgi and does not necessitate key Rab GTPases, AP adaptors, microtubules or endosomes.

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In an in silico search for correlated gene loss with fungal peroxisomal uric acid oxidase (UOX), we identified PMP22-like proteins, some of which function as promiscuous channels in organellar membranes. To investigate whether PMP22 channels have a role in peroxisomal uric acid transport and catabolism, we functionally analyzed the closest homologue in Aspergillus nidulans, named SspA. We confirmed that SspA is a peroxisomal membrane protein that co-localizes significantly with PTS1-tagged mRFP, UOX or HexA, the latter considered a protein of Woronin bodies (WB), organelles originating from peroxisomes that dynamically plug septal pores in ascomycetes.

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An 1H NMR-based metabonomic approach was used to investigate the correlation of histopathologically assessed tubulointerstitial lesions with the urinary metabolite profile in 77 patients with glomerulonephritides submitted to renal biopsy. The presence of renal damage was predicted with a sensitivity of 96% and a specificity of 99%. Patients with mild, moderate, and severe tubulointerstitial lesions were progressively differentiated from the healthy individuals in the Orthogonal Signal Correction Partial Least-Squares-Discriminant Analysis (OSC/PLS-DA) models with a statistically significant separation between those with mild and with severe lesions.

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Cutaneous metastases from breast adenocarcinoma are usually nodular, single or multiple. Their zosteriform distribution is very rare. We present a 54-year-old woman with cutaneous zosteriform nodular metastases on the right side of her thorax, and infiltration of the corresponding arm, 3 months after the excision of adenocarcinoma of her right breast.

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