Background: Parkinson's disease (PD) is the second most common neurodegenerative disease, following Alzheimer's. It is characterized by the aggregation of α-synuclein into Lewy bodies and Lewy neurites in the brain. Microglia-driven neuroinflammation may contribute to neuronal death in PD; however, the exact role of microglia remains unclear and has been understudied.
View Article and Find Full Text PDFBackground: Fragile X syndrome (FXS) is characterized by physical abnormalities, anxiety, intellectual disability, hyperactivity, autistic behaviors, and seizures. Abnormal neuronal development in FXS is poorly understood. Data on patients with FXS remain scarce, and FXS animal models have failed to yield successful therapies.
View Article and Find Full Text PDFProtein quality control (PQC) degradation systems protect the cell from the toxic accumulation of misfolded proteins. Because any protein can become misfolded, these systems must be able to distinguish abnormal proteins from normal ones, yet be capable of recognizing the wide variety of distinctly shaped misfolded proteins they are likely to encounter. How individual PQC degradation systems accomplish this remains an open question.
View Article and Find Full Text PDFThe cyclin-dependent kinase inhibitor p27(KIP1) is a tumor suppressor gene in mice, and loss of p27 protein is a negative prognostic indicator in human cancers. Unlike other tumor suppressors, the p27 gene is rarely mutated in tumors. Therefore misregulation of p27, rather than loss of the gene, is responsible for tumor-associated decreases in p27 protein levels.
View Article and Find Full Text PDFDecreased expression of the CDK inhibitor p27kip1 in human tumors directly correlates with increased resistance to chemotherapies, increased rates of metastasis, and an overall increased rate of patient mortality. It is thought that decreased p27 expression in tumors is caused by increased proteasomal turnover, in particular activation of the pathway governed by the SCFskp2 E3 ubiquitin protein ligase. We have directly tested the importance of the SCFskp-mediated degradation of p27 in tumorigenesis by analyzing the tumor susceptibility of mice that express a form of p27 that cannot be ubiquitinated and degraded by this pathway (p27T187A).
View Article and Find Full Text PDFBackground: Sister chromatid cohesion is needed for proper alignment and segregation of chromosomes during cell division. Chromatids are linked by the multiprotein cohesin complex, which binds to DNA during G(1) and then establishes cohesion during S phase DNA replication. However, many aspects of the mechanisms that establish and maintain cohesion during mitosis remain unclear.
View Article and Find Full Text PDFPrevious genetic studies indicated intersex (ix) functions only in females and that it acts near the end of the sex determination hierarchy to control somatic sexual differentiation in Drosophila melanogaster. We have cloned ix and characterized its function genetically, molecularly and biochemically. The ix pre-mRNA is not spliced, and ix mRNA is produced in both sexes.
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