Zebrafish GDNF and its co-receptor GFR alpha 1 activate the human RET receptor and promote the survival of dopaminergic neurons in vitro

Glial cell line-derived neurotrophic factor ( GDNF) is a ligand that activates, through coreceptor GDNF family receptor alpha-1 (GFR alpha 1) and receptor tyrosine kinase "RET ", several signaling pathways crucial in the development and sustainment of multiple neuronal populations. We decided to study whether non-mammalian orthologs of these three proteins have conserved their function: can they activate the human counterparts? Using the baculovirus expression system, we expressed and purified Danio rerio RET, and its binding partners GFRa1 and GDNF, and Drosophila melanogaster RET and two isoforms of coreceptor GDNF receptor-like. Our results report high-level insect cell expression of posttranslationally modified and dimerized zebrafish RET and its binding partners. We also found that zebrafish GFRa1 and GDNF are comparably active as mammalian cell- produced ones. We also report the first measurements of the affinity of the complex to RET in solution: at least for zebrafish, the Kd for GFR alpha 1-GDNF binding RET is 5.9 mu M. Surprisingly, we also found that zebrafish GDNF as well as zebrafish GFRa1 robustly activated human RET signaling and promoted the survival of cultured mouse dopaminergic neurons with comparable efficiency to mammalian GDNF, unlike E. coli-produced human proteins. These results contradict previous studies suggesting that mammalian GFRa1 and GDNF cannot bind and activate non-mammalian RET and vice versa.Peer reviewe

Cytogenomic Profile of Uterine Leiomyoma: In Vivo vs. In Vitro Comparison

We performed a comparative cytogenomic analysis of cultured and uncultured uterine leiomyoma (UL) samples. The experimental approach included karyotyping, aCGH, verification of the detected chromosomal abnormalities by metaphase and interphase FISH, MED12 mutation analysis and telomere measurement by Q-FISH. An abnormal karyotype was detected in 12 out of 32 cultured UL samples. In five karyotypically abnormal ULs, MED12 mutations were found. The chromosomal abnormalities in ULs were present mostly by complex rearrangements, including chromothripsis. In both karyotypically normal and abnormal ULs, telomeres were ~40% shorter than in the corresponding myometrium, being possibly prerequisite to chromosomal rearrangements. The uncultured samples of six karyotypically abnormal ULs were checked for the detected chromosomal abnormalities through interphase FISH with individually designed DNA probe sets. All chromosomal abnormalities detected in cultured ULs were found in corresponding uncultured samples. In all tumors, clonal spectra were present by the karyotypically abnormal cell clone/clones which coexisted with karyotypically normal ones, suggesting that chromosomal abnormalities acted as drivers, rather than triggers, of the neoplastic process. In vitro propagation did not cause any changes in the spectrum of the cell clones, but altered their ratio compared to uncultured sample. The alterations were unique for every UL. Compared to its uncultured counterpart, the frequency of chromosomally abnormal cells in the cultured sample was higher in some ULs and lower in others. To summarize, ULs are characterized by both inter- and intratumor genetic heterogeneity. Regardless of its MED12 status, a tumor may be comprised of clones with and without chromosomal abnormalities. In contrast to the clonal spectrum, which is unique and constant for each UL, the clonal frequency demonstrates up or down shifts under in vitro conditions, most probably determined by the unequal ability of cells with different genetic aberrations to exist outside the body

Overview Of Data Over Digital Subscrieber Line In Czech Republic.

Import 22/07/2015Tato bakalářská práce je zaměřena na rozbor technologie ADSL a to, jak je využívána a nabízena vybranými poskytovateli v České republice k užívání veřejným sektorem. V teoretické části pojednává o technologii ADSL a jejích vývojových verzích. Dále se zabývá řešením přípojky a vlivů rušení na vedení těchto přípojek. Hlavní částí práce je část praktická, ta se zabývá průzkumem poskytovatelů v České republice. Konkrétně využitím digitálních účastnických smyček poskytovateli, jejich nabídkou ADSL služeb pevného připojení k internetu a také doplňkových služeb a poplatků s pevným připojením spojených. Poslední částí práce je analýza možností připojení těchto služeb na konkrétní přípojku. Obsah této práce má napomoci běžným uživatelům k pochopení dané problematiky spojené se zřízením a výběrem ADSL služeb. Prostředky k řešení praktické části práce jsou především komunikace s poskytovateli ADSL služeb a získávání informací.This bachelor thesis is focused on the analysis of the technology ADSL as it is used in the public sector and offered by chosen providers in Czech Republic. In the theoretical part, it refers to the technology ADSL and its developmental versions. Furthermore, it examines the connection solution and the influence of interruption on conducting these connections. The main part of the thesis is the practical part which undertakes the research of providers in Czech Republic. Namely, it explores use of digital subscriber loops by providers, theirs ADSL service offers of the stable internet connection and its complementary services and charges. The final part of the thesis is the connection analysis of these complementary services on the specific connection. The content of this thesis should provide help to common users to understand given issues related to the selection and setting up ADSL services. Tools used for the practical part are particularly communication with ADSL service providers and acquiring appropriate information.440 - Katedra telekomunikační technikyvýborn

zGDNF activates hRET phosphorylation as shown by anti-phospho-RET western blotting.

<p>The anti-phosphotyrosine (pY) Western blotting reflects the level of phosphorylated tyrosine residues in RET (upper panels); anti-RET western blotting (lower panels) demonstrates equal loading in different samples. hGDNF^IC, hGDNF^BV and hGDNF^Ec produced hGDNF were used as controls at a range of concentrations stated in nM and media as a negative control.</p

Biolayer inferometry (BLItz) of zebrafish proteins.

<p>Scatchard plot showing the binding of zRET^ecd and zGDNF to pre-incubated zGFRα1 using BLItz. The x-axis shows the concentration of zGDNF and zRET^ecd. The dashed line indicates the nonlinear curve fit plotted by GraphPad Prism 6 for single-site binding.</p

Amino acid sequence alignment of zebrafish, human, rat, frog and fruit fly GFRα1.

<p>The red letters indicate sequence identity and blue letter sequence similarity. Dashed box indicates signal sequence. The dotted line indicates the start and end of domains 2 and 3. Solid box indicates the amino acid E323/D324 (rat), E326/E327 (zebrafish), D321/D322 (frog) predicted to be involved in hRET complex formation.</p