41 research outputs found

    Molecular cloning and expression of bovine nucleoplasmin 2 (NPM2): a maternal effect gene regulated by miR-181a

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    Background Nucleoplasmin 2 (NPM2) is an oocyte-specific nuclear protein essential for nuclear and nucleolar organization and early embryonic development. The aims of this study were to clone the bovine NPM2 gene, determine its temporal expression during oocyte development and early embryogenesis, and evaluate the potential role of miRNA-181a in regulation of its expression. Methods A 329 bp cDNA fragment was amplified from bovine fetal ovary using primers designed based on the conserved regions of the human and mouse NPM2 cDNA sequences. RACE experiments were performed to obtain the 5\u27 and 3\u27 ends of the bovine NPM2 cDNA. Real time PCR and Western blot analysis were used to examine the expression of bovine NPM2 in oocytes and early embryos. Co-expression of bovine NPM2 and miRNA-181a in Hela cells was performed to determine if expression of bovine NPM2 is regulated by miRNA-181a. Results The bovine NPM2 cDNA is 851 bp in length encoding a protein of 200 amino acids. The protein contains the conserved bipartite nuclear localization sequence and shows 53% and 62% identity with mouse and human NPM2, respectively. Expression of bovine NPM2 mRNA is restricted to ovaries. NPM2 mRNA is abundant in GV and MII stage oocytes, decreases in early cleavage stage embryos, and barely detectable in morula and blastocyst stage embryos. Similarly, expression of NPM2 protein is high in oocytes and early embryos but extremely low in blastocysts. The abundance of NPM2 mRNA is significantly lower in oocytes isolated from persistent versus growing dominant follicles (P \u3c 0.05). A miR-181a binding site in the 3\u27UTR of the NPM2transcript was identified. Transfection experiments showed that bovine NPM2 protein expression is reduced in Hela cells expressing miR-181a compared to control cells without miR-181a, indicating that translation of NPM2 is repressed by miR-181a. Conclusions Our data suggest that expression of bovine NPM2 is temporally regulated during early embryogenesis and miR-181a may play a role in its regulation

    Diversification of importin-α isoforms in cellular trafficking and disease states.

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    The human genome encodes seven isoforms of importin α which are grouped into three subfamilies known as α1, α2 and α3. All isoforms share a fundamentally conserved architecture that consists of an N-terminal, autoinhibitory, importin-β-binding (IBB) domain and a C-terminal Arm (Armadillo)-core that associates with nuclear localization signal (NLS) cargoes. Despite striking similarity in amino acid sequence and 3D structure, importin-α isoforms display remarkable substrate specificity in vivo. In the present review, we look at key differences among importin-α isoforms and provide a comprehensive inventory of known viral and cellular cargoes that have been shown to associate preferentially with specific isoforms. We illustrate how the diversification of the adaptor importin α into seven isoforms expands the dynamic range and regulatory control of nucleocytoplasmic transport, offering unexpected opportunities for pharmacological intervention. The emerging view of importin α is that of a key signalling molecule, with isoforms that confer preferential nuclear entry and spatiotemporal specificity on viral and cellular cargoes directly linked to human diseases

    Inverse kinematics of a 6 DoF human upper limb using ANFIS and ANN for anticipatory actuation in ADL-based physical Neurorehabilitation

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    Objective: This research is focused in the creation and validation of a solution to the inverse kinematics problem for a 6 degrees of freedom human upper limb. This system is intended to work within a realtime dysfunctional motion prediction system that allows anticipatory actuation in physical Neurorehabilitation under the assisted-as-needed paradigm. For this purpose, a multilayer perceptron-based and an ANFIS-based solution to the inverse kinematics problem are evaluated. Materials and methods: Both the multilayer perceptron-based and the ANFIS-based inverse kinematics methods have been trained with three-dimensional Cartesian positions corresponding to the end-effector of healthy human upper limbs that execute two different activities of the daily life: "serving water from a jar" and "picking up a bottle". Validation of the proposed methodologies has been performed by a 10 fold cross-validation procedure. Results: Once trained, the systems are able to map 3D positions of the end-effector to the corresponding healthy biomechanical configurations. A high mean correlation coefficient and a low root mean squared error have been found for both the multilayer perceptron and ANFIS-based methods. Conclusions: The obtained results indicate that both systems effectively solve the inverse kinematics problem, but, due to its low computational load, crucial in real-time applications, along with its high performance, a multilayer perceptron-based solution, consisting in 3 input neurons, 1 hidden layer with 3 neurons and 6 output neurons has been considered the most appropriated for the target application

    Importin α7 Is Essential for Zygotic Genome Activation and Early Mouse Development

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    Importin α is involved in the nuclear import of proteins. It also contributes to spindle assembly and nuclear membrane formation, however, the underlying mechanisms are poorly understood. Here, we studied the function of importin α7 by gene targeting in mice and show that it is essential for early embryonic development. Embryos lacking importin α7 display a reduced ability for the first cleavage and arrest completely at the two-cell stage. We show that the zygotic genome activation is severely disturbed in these embryos. Our findings indicate that importin α7 is a new member of the small group of maternal effect genes

    Autosomal recessive mutations in nuclear transport factor KPNA7 are associated with infantile spasms and cerebellar malformation

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    Nuclear import receptors of the KPNA family recognize the nuclear localization signal in proteins and together with importin-β mediate translocation into the nucleus. Accordingly, KPNA family members have a highly conserved architecture with domains that contact the nuclear localization signal and bind to importin-β. Here, we describe autosomal recessive mutations in KPNA7 found by whole exome sequencing in a sibling pair with severe developmental disability, infantile spasms, subsequent intractable epilepsy consistent with Lennox–Gastaut syndrome, partial agenesis of the corpus callosum, and cerebellar vermis hypoplasia. The mutations mapped to exon 7 in KPNA7 result in two amino-acid substitutions, Pro339Ala and Glu344Gln. On the basis of the crystal structure of the paralog KPNA2 bound to a bipartite nuclear localization signal from the retinoblastoma protein, the amino-acid substitutions in the affected subjects were predicted to occur within the seventh armadillo repeat that forms one of the two nuclear localization signal-binding sites in KPNA family members. Glu344 is conserved in all seven KPNA proteins, and we found that the Glu354Gln mutation in KPNA2 is sufficient to reduce binding to the retinoblastoma nuclear localization signal to approximately one-half that of wild-type protein. Our data show that compound heterozygous mutations in KPNA7 are associated with a human neurodevelopmental disease, and provide the first example of a human disease associated with mutation of a nuclear transport receptor

    Autologous stem cell transplantation for multiple myeloma: identification of prognostic factors

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    Introduction: The purpose of this study was to evaluate the effect of prognostic factors on the outcome of patients with MM after ASCT. Patients and Methods: We analyzed results of 170 consecutive patients (121 male and 49 female) of MM who underwent ASCT. Patients' median age was 52 years (range, 26-68 years). High dose melphalan (200 mg/m2) was used for conditioning. One hundred thirty-two patients (77.6%) had evidence of chemosensitive disease before transplant. Response was assessed using European Group for Blood and Bone Marrow Transplantation criteria. Results: Post ASCT 44.7% of patients achieved CR, 24.7% had very good partial response (VGPR), and 21.2% had partial response (PR). Presence of pretransplant chemosensitive disease (CR, VGPR, and PR) and transplant within 12 months of diagnosis for years before 2006 were associated with higher response rates on multivariate analysis. At a median follow-up of 84 months, median overall (OS) and event-free survival (EFS) is 85.5 and 41 months, respectively. Estimated OS and EFS at 60 months is 62 ± 0.04% and 41 ± 0.04%, respectively. Patients who responded to transplant (CR, VGPR, and PR) had a longer OS (P < .001) and EFS (P < .001). Additionally, patients who achieved CR post transplant had a longer OS (P < .001) and EFS (P < .001). Patients who received novel agents for induction pretransplant had a longer OS (P < .001) and EFS (P < .002). Conclusion: Outcome after ASCT is better for myeloma patients with pretransplant chemosensitive disease and those who achieve CR after transplant
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