The urokinase receptor, cell migration, proliferation and cancer

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Purification and characterization of UEF3, a novel factor involved in the regulation of the urokinase and other AP-1 controlled promoters.

Basal as well as induced transcription from the human urokinase-type plasminogen activator gene requires an enhancer containing two elements, a combined PEA3/AP-1 and a consensus AP-1 site. The integrity of each of these binding sites as well as their cooperation is required for activating transcription. The two elements are separated by a 74-base pair cooperation mediating (COM) region required for the cooperation between the transactivating sites. The COM region contains binding sites for four different unidentified urokinase-type plasminogen activator enhancer factors (UEF 1 to 4), all four required for correct COM activity. We have purified UEF3 from HeLa nuclear extracts by several chromatographic steps including DNA affinity purification. Purification and UV cross-linking data showed that UEF3 is a complex of three polypeptides (p40, p50, and p64). Amino acid sequence from one peptide of p64 was obtained, which showed no homology to other known proteins. Both crude and purified UEF3 specifically bound to the sequence TGACAG as shown by electrophoretic mobility shifts and methylation interference studies. DNA-binding specificity of purified UEF3 was identical to that of NIP, a non-characterized factor binding and regulating multiple AP-1-regulated promoters like stromelysin and interleukin-3. Thus UEF3 appears to be a general DNA-binding factor involved in modulating the transcriptional response of AP-1 containing promoters

Thyroidal phenylpyruvate tautomerase. Isolation and characterization.

Hog thyroid tautomerase (EC 5.3.2.1, phenylpyruvate keto-enol isomerase), an enzyme which is believed to play a role in the biosynthesis of thyroxine, has been purified over 1000-fold. The purification procedure involves a heat step at 70°, gel filtration on Sephadex G-100, ion exchange chromatography on carboxymethyl Sephadex C-50, and, finally, gel filtration on Sephadex G-50. The enzyme is homogeneous by the following criteria. It gives a single peak in sedimentation velocity analysis and shows a single band on disc polyacrylamide gel and starch gel electrophoresis, and the sedimentation equilibrium plot is linear, even at the lowest protein concentrations. The pH optimum of the purified tautomerase is 6.2. Its molecular weight is 44,000. The amino acid composition of the enzyme, as well as some of its physico-chemical properties, are presented. The enzyme is able to substitute for borate ions in the coupling reaction of thyroxine synthesis

Overexpression of PREP-1 in F9 Teratocarcinoma Cells Leads to a Functionally Relevant Increase of PBX-2 by Preventing Its Degradation

To bind DNA and to be retained in the nucleus, PBX proteins must form heterodimeric complexes with members of the MEINOX family. Therefore the balance between PBX and MEINOX must be an important regulatory feature. We show that overexpression of PREP-1 influences the level of PBX-2 protein maintaining the PREP-1-PBX balance. This effect has important functional consequences. F9 teratocarcinoma cells stably transfected with PREP-1 had an increased DNA binding activity to a PREP-PBX-responsive element. Because PREP-1 binds DNA efficiently only when dimerized to PBX, the increased DNA binding activity suggests that the level of PBX might also have increased. Indeed PREP-1-overexpressing cells had a higher level of PBX-2 and PBX-1b proteins. PBX-2 increase did not depend on increased mRNA level or a higher rate of translation but rather because of a protein stabilization process. Indeed, PBX-2 level drastically decreased after 3 h of cycloheximide treatment in control but not in PREP-1-overexpressing cells and the proteasome inhibitor MG132 prevented PBX-2 decay in control cells. Hence, dimerization with PREP-1 appears to decrease proteasomal degradation of PBX-2. Retinoic acid induces differentiation of F9 teratocarcinoma cells with a cascade synthesis of HOX proteins. In PREP-1-overexpressing cells, HOXb1 induction was more sustained (3 days versus 1 day) and the induced level of MEIS-1b, another TALE (three amino acid loop extension) protein involved in embryonal development, was higher. Thus an increase in PREP-1 leads to changes in the fate-determining HOXb1 and has therefore important functional consequences

The genetics and the molecular functions of the PREP1 homeodomain transcription factor

Prep1 (pKnox1) is a homeodomain transcription factor of the TALE superclass whose members can act as co-factors of Hox. Prep1 is essential for embryogenesis, but in the adult it also acts as a tumor suppressor. We describe and analyze here the available mutant mice, their phenotypes and a few discordant cases. Moreover we specify the basic rules underlying the binding of Prep1 and its TALE partners to DNA, and their plasticity during embryonic development. We finally review recent data on Prep1 which indicate a very basic cellular function at the level of DNA replication and DNA damage

Helping managers to assist employees’ job crafting and well-being. An integrated (Top-down, Bottom-up) approach to job re-design

Job crafting is a promising method of job re-design to improve the person-job fit (P-J fit) and well-being. From previous research, it emerges that line managers may be critical to facilitate bottom-up job re-design and employees’ well-being. Nevertheless, no research has investigated the impact of top-down management development alongside bottom-up job re-design interventions or has purposefully integrated top-down and bottom-up elements in job re-design. Top-down and bottom-up interventions were designed and implemented in two organisations. Repeated-measures data were collected three weeks before (Time1/baseline) and four months after (Time 2/follow-up) the interventions. In study 1, involving 276 call-centre agents, participants in the bottom-up intervention reported an increase in job satisfaction and social resources at T2 compared with a wait-list control group. Participants in the top-down intervention reported an increase, via direct and indirect effects, in job crafting, specific job characteristics, P-J fit, coping efficacy, meaning at work, well-being, and job satisfaction at T2 compared with a wait-list control group. No interaction effects were found between the interventions. In study 2, involving 88 police officers, participants in the bottom-up intervention reported a decrease in structural resources, P-J fit, coping efficacy, and meaning at work at T2 compared with a wait-list control group. An interaction effect was found through which the (bottom-up and top-down) interventions enhanced well-being. Unplanned structural changes may have had an impact on the results of study 2, highlighting the challenges of intervention research in changing contexts. The thesis provides several contributions, including evidence on the combined effects of two different interventions, which both had some beneficial effects. It also provides evidence of the mechanisms through which the interventions, job crafting, and job crafting-related outcomes positively impact well-being and job satisfaction. Keywords: job re-design, real-world interventions, job crafting, job characteristics, person-job fit, meaning at work, coping efficacy, well-being, structural modelling

The Propionibacterium spp. extract reduces Candida albicans-induced damage to vaginal epithelial cells and increases mitochondrial response to Candida albicans infection in vitro

Introduction. Bacterial lysates are prepared by inactivated microorganisms and are extensively employed in clinical settings as immunomodulants and to improve mucosal immunity. However, despite their extensive clinical use, their effects on the host are only partially known. The Propionibacterium spp. extract (PE) is a bacterial lysate included as an active compound in a gel formulation used to treat the symptoms of vulvovaginal candidiasis. Here, we analyzed its possible beneficial effects in an in vitro model of vaginal epithelial cells infected with Candida. Materials and Methods. Initially, we analyzed the PE effects on C. albicans and C. parapsilosis growth by the microdilution method. We then assessed the capacity of PE to reduce C. albicans-induced damage of vaginal epithelial cells through the quantification of lactate-dehydrogenase released by damaged cells in the growth medium. Moreover, in order to test the capacity of the PE to modulate epithelial mitochondrial activity, we evaluated Reactive-Oxygen-Species (ROS) production by the infected epithelial cells, stimulated or not with PE. This was kinetically monitored through the analysis of emitted fluorescence, after addition of the MitoSOX Red probe. Results. Our results show that PE did not affect directly microbial growth. In addition, the epithelial cells stimulation with PE reduced C. albicans-induced cell damage. Moreover, the treatment with PE increased the epithelial cells mitochondrial activity in response to C. albicans infection in vitro. Discussion and Conclusions. Taken together, our results show that PE increases ROS production by epithelial cells in response to C. albicans infection. Therefore, our results suggest that the increased mitochondrial activity induced by PE, could protect epithelial cells against the damage induced by C. albicans infection