A proposed mechanism for sorting secretory proteins into granules for release via the regulated secretory pathway in endocrine-neuroendocrine cells involves binding the proteins to a sorting receptor at the trans-Golgi network, followed by budding and granule formation. We have identified such a sorting receptor as membrane-associated carboxypeptidase E (CPE) in pituitary Golgi-enriched and secretory granule membranes. CPE specifically bound regulated secretory pathway proteins, including prohormones, but not constitutively secreted proteins. We show that in the Cpe(fat) mutant mouse lacking CPE, the pituitary prohormone, pro-opiomelanocortin, was missorted to the constitutive pathway and secreted in an unregulated manner. Thus, obliteration of CPE, the sorting receptor, leads to multiple endocrine disorders in these genetically defective mice, including hyperproinsulinemia and infertility.
In this study, we have investigated the intrinsic peroxidase-like activity of citrate-capped AuNPs (perAuxidase) and demonstrated that the nanozyme function can be multiplexed and tuned by integrating oligonucleotides on a nanoparticle surface. Systematic studies revealed that by controlling the reaction parameters, the mutiplexing effect can be delayed or advanced and further used for aptasensor applications.
Metal-mediated base pairs have been extensively utilized in many research fields, including genetic-code extension, novel therapeutics development, and nanodevice design. Compared to other cations, Ag is more flexible in pairing with natural base pairs. Herein, we present a DNA structure containing two C-Ag -C pairs and the first reported G-Ag -G pair in a short 8mer DNA strand. This structure not only provides detailed insight into these Ag -mediated base-pairing patterns in DNA, but also represents the first nonhelical DNA structure driven by heavy-metal ions, thus further contributing to the structural diversity of DNA. This unique complex structure is highly sequence-dependent, thus implying functional potentials as a new DNA aptamer that can bind and recognize silver ions. These results not only advance our understanding of the interactions between Ag and nucleobases, but also provide a unique structural component for the rational design of new DNA nanodevices.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.