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A-kinase anchoring protein 12 (AKAP12) is known to function as a scaffold protein and as a putative tumor suppressor. However, little is known about the biological role of AKAP12 in hepatic cells. In this study, we performed micro-array analysis to identify the downstream pathway of AKAP12A, and found that AKAP12A overexpression up-regulates the expressions of several cholesterol-associated genes including HMG-CoA reductase and LDL receptor, which have been reported to be controlled by sterol regulatory element binding protein-2 (SREBP-2). It was found that AKAP12A activates SREBP-2 in hepatic cells, as demonstrated by the presence of its cleavage product, whereas the activation of sterol regulatory element binding protein-1 was not remarkably changed. Moreover, AKAP12A-induced SREBP-2 activation was found to depend on SREBP cleavage-activating protein (SCAP), as inhibition of SCAP by RNAi or sterols blocked SREBP-2 activation in response to AKAP12A overexpression. Interestingly, the hydrophobic amine U18666A caused dramatic movement of AKAP12A from the plasma membrane to cytosol and lysosomal membranes. Moreover, cholesterol depletion from the plasma membrane (using methyl-beta-cyclodextrin) caused a shift of AKAP12A from the plasma membrane to the cytoplasm. Cholesterol binding assay revealed that the N-terminal region of AKAP12A binds directly to cholesterol in vitro. Furthermore, AKAP12A overexpression enhanced [3H]-cholesterol efflux to extracellular acceptors, suggesting that AKAP12A may activate SREBP-2 by increasing cholesterol efflux. In conclusion, the present study suggests that AKAP12A is a novel regulator of cellular cholesterol metabolism. ; This work was supported in part by grants from the Ministry of Science & Technology of Korea through theNational Research Laboratory Program for Cancer Epigenetics, by the Korea Research Foundation Grant funded by the Korean Government (MOEHRD, Basic Research Promotion Fund) (#KRF-2004- 217-C00011), and by BK21 Project for Medicine, Dentistry, and Pharmacy.

The focus of this book is on the role of protein metabolism and homeostasis in aging. An overview is provided of the current knowledge in the area, including protein synthesis, accuracy and repair, post-translational modifications, degradation and turnover, and how they define and influence aging. The chapters mainly focus on well-characterized factors and pathways, but new areas are also presented, where associations with aging are just being elucidated by current experimental data.

Seaweeds are a typical food of East-Asian cuisine, to which are alleged several beneficial health effects have been attributed. Their availability and their nutritional and chemical composition have favored the increase in its consumption worldwide, as well as a focus of research due to their bioactive properties. In this regard, seaweed proteins are nutritionally valuable and comprise several specific enzymes, glycoproteins, cell wall-attached proteins, red algae phycobiliproteins, lectins, peptides, or mycosporine-like amino acids. This great extent of molecules has been reported to exert significant antioxidant, antimicrobial, anti-inflammatory, antihypertensive, antidiabetic, or antitumoral properties. Hence, knowledge on algae proteins and derived compounds have gained special interest for the potential nutraceutical, cosmetic or pharmaceutical industries based on these bioactivities. Although several molecular mechanisms of action on how these proteins and peptides exert biological activities have been described, many gaps in knowledge still need to be filled. Updating the current knowledge related to seaweed proteins and peptides is of interest to further asses their potential health benefits. This review addresses the characteristics of seaweed protein and protein-derived molecules, their natural occurrence, their studied bioactive properties, and their described potential mechanisms of action. ; The research leading to these results was supported by MICINN supporting the Ramón y Cajal grant for M.A. Prieto (RYC-2017-22891), to Xunta de Galicia for the pre-doctoral grant of P. Garcia-Oliveira (ED481A-2019/295), the program Grupos de Referencia Competitiva (GRUPO AA1-GRC 2018) that supports the work of J. Echave, to the Bio Based Industries Joint Undertaking (JU) under grant agreement No 888003 UP4HEALTH Project (H2020-BBI-JTI-2019) that supports the work of P. Otero. The JU receives support from the European Union's Horizon 2020 research and innovation program and the Bio Based Industries Consortium. ...

Three fundamental processes running in plant organisms under influence of environment (light, gravity) and key importance were considered. In the light case these are phytоchrome regulation and phototropism considering process is gravitropism. Phytochrome is responsible for regulatory reaction at the inhibition of which the plants cannot be normally developed. The plants do not need phototropism and gravitropism. They were elaborated by evolution as protective reactions to optimize the plant vitality. All these processes are realized according to one and the same logical scheme: stimulus reception, signaling processes in plant cell (transduction) and proper biological effect. According to this scheme the three reactions were considered. As the result the data adout the reception stages are principally different because receptor nature. Signaling processes proceed with participation of many low molecular and high molecular mediators to participate and biophysical, biochemical and genetic reactions. One fact attracts attention that the same mediators are involved to signaling ending by principally different final biological effect.This allows to suggest the existance in plant cell no separate chains for each stimulus but regulatory network formed by lateral and horizontal transduction chains.

Seaweeds are industrially exploited for obtaining pigments, polysaccharides, or phenolic compounds with application in diverse fields. Nevertheless, their rich composition in fiber, minerals, and proteins, has pointed them as a useful source of these components. Seaweed proteins are nutritionally valuable and include several specific enzymes, glycoproteins, cell wall-attached proteins, phycobiliproteins, lectins, or peptides. Extraction of seaweed proteins requires the application of disruptive methods due to the heterogeneous cell wall composition of each macroalgae group. Hence, non-protein molecules like phenolics or polysaccharides may also be co-extracted, affecting the extraction yield. Therefore, depending on the macroalgae and target protein characteristics, the sample pretreatment, extraction and purification techniques must be carefully chosen. Traditional methods like solid–liquid or enzyme-assisted extraction (SLE or EAE) have proven successful. However, alternative techniques as ultrasound- or microwave-assisted extraction (UAE or MAE) can be more efficient. To obtain protein hydrolysates, these proteins are subjected to hydrolyzation reactions, whether with proteases or physical or chemical treatments that disrupt the proteins native folding. These hydrolysates and derived peptides are accounted for bioactive properties, like antioxidant, anti-inflammatory, antimicrobial, or antihypertensive activities, which can be applied to different sectors. In this work, current methods and challenges for protein extraction and purification from seaweeds are addressed, focusing on their potential industrial applications in the food, cosmetic, and pharmaceutical industries. ; The authors are grateful to the program Grupos de Referencia Competitiva (GRUPO AA1-GRC 2018) that supports the work of J. Echave, to the Bio Based Industries Joint Undertaking (JU) under grant agreement No. 888003 UP4HEALTH Project (H2020-BBI-JTI-2019) that supports the work of P. Garcia-Perez. The JU receives support from the European Union's Horizon 2020 research and innovation program and the Bio Based Industries Consortium. The project SYSTEMIC Knowledge Hub on Nutrition and Food Security has received funding from national research funding parties in Belgium (FWO), France (INRA), Germany (BLE), Italy (MIPAAF), Latvia (IZM), Norway (RCN), Portugal (FCT), and Spain (AEI) in a joint action of JPI HDHL, JPI-OCEANS, and FACCE-JPI, launched in 2019 under the ERA-NET ERA-HDHL (No. 696295). ; info:eu-repo/semantics/publishedVersion