Microbial infection leads to proteolytic activation of Drosophila spätzle, which binds to the toll receptor and induces the synthesis of immune proteins. To test whether or not this mechanism exists in lepidopteran insects, we cloned the cDNA of Bombyx mori spätzle-1 and overexpressed the full-length and truncated BmSpz1 cDNA in Escherichia coli. The insoluble fusion proteins were affinity-purified under denaturing condition. After the silkworm larvae were injected with renatured BmSpz1, mRNA levels of antimicrobial peptide genes greatly increased. Similar transcriptional up-regulation was also found in Manduca sexta. Injection of pro-BmSpz1 had no such effect. When pro-BmSpz1 and Micrococcus luteus were incubated with the plasma from M. sexta larvae, we detected proteolytic processing of pro-BmSpz1. These results suggest that active spätzle is required for the induced production of antimicrobial peptides in B. mori and M. sexta.
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http://dx.doi.org/10.1016/j.dci.2007.01.001 | DOI Listing |
J Neuroinflammation
January 2025
Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI, USA.
The thrombolytic protease tissue plasminogen activator (tPA) is expressed in the CNS, where it regulates diverse functions including neuronal plasticity, neuroinflammation, and blood-brain-barrier integrity. However, its role in different brain regions such as the substantia nigra (SN) is largely unexplored. In this study, we characterize tPA expression, activity, and localization in the SN using a combination of retrograde tracing and β-galactosidase tPA reporter mice.
View Article and Find Full Text PDFBiometals
January 2025
Instituto de Química, Universidade de São Paulo, Av. Lineu Prestes 748, São Paulo, 05508-000, Brazil.
Zinc is an essential metal to living organisms, including corals and their symbiotic microalgae (Symbiodiniaceae). Both Zn(II) deprivation and overload are capable of leading to dysfunctional metabolism, coral bleaching, and even organism death. The present work investigated the effects of chemically defined Zn species (free Zn, ZnO nanoparticles, and the complexes Zn-histidinate and Zn-EDTA) over the growth of the dinoflagellates Symbiodinium microadriaticum, Breviolum minutum, and Effrenium voratum, and on the trypsin-like proteolytic activity of the hydrocoral Millepora alcicornis.
View Article and Find Full Text PDFHuman amylin, called also islet amyloid polypeptide (hIAPP), is the principal constituent of amyloid deposits in the pancreatic islets. Together with hyperglycemia, hIAPP-derived oligomers and aggregates are important culprits in type 2 diabetes mellitus (T2DM). Preventing aggregation, and in particular inhibiting the formation and/or stimulating degradation of toxic amylin oligomers formed early in the process, may reduce the negative effects of T2DM.
View Article and Find Full Text PDFEur J Med Chem
January 2025
Institute of Translational Medicine, Shanghai University, Shanghai, 200444, China; Shanghai Integration and Innovation Center of Marine Medical Engineering, China. Electronic address:
The identification of novel molecular candidates capable of treating osteoarthritis (OA) has significant clinical implications. Monocyte locomotion inhibitory factor peptide (MLIF) is a pentapeptide derived from Entamoeba histolytica. It has been found possesses selective anti-inflammatory effects both in vitro and in vivo.
View Article and Find Full Text PDFJ Chem Inf Model
January 2025
State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200030, P.R. China.
The rise of resistance to antiretroviral drugs due to mutations in human immunodeficiency virus-1 (HIV-1) protease is a major obstacle to effective treatment. These mutations alter the drug-binding pocket of the protease and reduce the drug efficacy by disrupting interactions with inhibitors. Traditional methods, such as biochemical assays and structural biology, are crucial for studying enzyme function but are time-consuming and labor-intensive.
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