Identification of Hydroxyproline-Containing Proteins and Hydroxylation of Proline Residues in Rice

Glycosylated Polyhydroxyproline Is a Potent Antifreeze Molecule

Molecules that inhibit the growth of ice crystals are highly desirable for applications in building materials, foods, and agriculture. Antifreezes are particularly essential in biomedicine for tissue banking, yet molecules currently in use have known toxic effects. Antifreeze glycoproteins have evolved naturally in polar fish species living in subzero climates, but practical issues with collection and purification have limited their commercial use. Here, we present a synthetic strategy using polymerization of amino acid N-carboxyanhydrides to produce polypeptide mimics of these potent natural antifreeze proteins. We investigated a set of mimics with varied structural properties and identified a glycopolypeptide with potent ice recrystallization inhibition properties. We optimized for molecular weight, characterized their conformations, and verified their cytocompatibility in a human cell line. Overall, we present a material that will have broad applications as a biocompatible antifreeze.

Applications of the Yariv reagent in polysaccharide analysis and plant physiology from theory to practice

Arabinogalactan (AG), a biologically active substance found abundantly in plants, is of significant interest in plant physiology due to its unique physicochemical properties. Yariv reagent, widely utilized in AG-II related applications, forms insoluble precipitates when bound to AG-II. This paper provides a comprehensive overview of the synthesis methods, physicochemical properties, and various dissociation methods of the Yariv reagent to enhance its utility in AG-II studies. Furthermore, the review explores the binding mechanisms and applications of the Yariv reagent, highlighting the advancements in studying the Yariv-AG complex in plant physiology. The aim of this review is to inspire new research ideas and foster novel applications of the Yariv reagent from synthesis to implementation.

Challenges Coexist with Opportunities: Spatial Heterogeneity Expression of PD-L1 in Cancer Therapy

Cancer immunotherapy using anti-programmed death-ligand 1 (PD-L1) antibodies has been used in various clinical applications and achieved certain results. However, such limitations as autoimmunity, tumor hyperprogression, and overall low patient response rate impede its further clinical application. Mounting evidence has revealed that PD-L1 is not only present in tumor cell membrane but also in cytoplasm, exosome, or even nucleus. Among these, the dynamic and spatial heterogeneous expression of PD-L1 in tumors is mainly responsible for the unsatisfactory efficacy of PD-L1 antibodies. Hence, numerous studies focus on inhibiting or degrading PD-L1 to improve immune response, while a comprehensive understanding of the molecular mechanisms underlying spatial heterogeneity of PD-L1 can fundamentally transform the current status of PD-L1 antibodies in clinical development. Herein, the concept of spatial heterogeneous expression of PD-L1 is creatively introduced, encompassing the structure and biological functions of various kinds of PD-L1 (including mPD-L1, cPD-L1, nPD-L1, and exoPD-L1). Then an in-depth analysis of the regulatory mechanisms and potential therapeutic targets of PD-L1 is provided, seeking to offer a solid basis for future investigation. Moreover, the current status of agents is summarized, especially small molecular modulators development directed at these new targets, offering a novel perspective on potential PD-L1 therapeutics strategies.