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Acta Biomaterialia Aug 2018Cell-free (CF) protein synthesis has emerged as a powerful technique platform for efficient protein production in vitro. Liposomes have been widely studied as... (Review)
Review
UNLABELLED
Cell-free (CF) protein synthesis has emerged as a powerful technique platform for efficient protein production in vitro. Liposomes have been widely studied as therapeutic carriers due to their biocompatibility, biodegradability, low toxicity, flexible surface manipulation, easy preparation, and higher cargo encapsulation capability. However, rapid immune clearance, insufficient targeting capacity, and poor cytoplasmic delivery efficiency substantially restrict their clinical application. The incorporation of functional membrane proteins (MPs) or peptides allows the transfer of biological properties to liposomes and imparts them with improved circulation, increased targeting, and efficient intracellular delivery. Liposome-chaperoned CF synthesis enables production of proteoliposomes in one-step reaction, which not only substantially simplifies the production procedure but also keeps protein functionality intact. Building off these observations, proteoliposomes with integrated MPs represent an excellent candidate for therapeutic delivery. In this review, we describe recent advances in CF synthesis with emphasis on detailing key factors for improving CF expression efficiency. Furthermore, we provide insights into strategies for rational design of proteoliposomal nanodelivery systems via CF synthesis.
STATEMENT OF SIGNIFICANCE
Liposome-chaperoned CF synthesis has emerged as a powerful approach for the design of recombinant proteoliposomes in one-step reaction. The incorporation of bioactive MPs or peptides into liposomes via CF synthesis can facilitate the development of proteoliposomal nanodelivery systems with improved circulation, increased targeting, and enhanced cellular delivery capacity. Moreover, by adapting lessons learned from natural delivery vehicles, novel bio-inspired proteoliposomes with enhanced delivery properties could be produced in CF systems. In this review, we first give an overview of CF synthesis with focus on enhancing protein expression in liposome-chaperoned CF systems. Furthermore, we intend to provide insight into harnessing CF-synthesized proteoliposomes for efficient therapeutic delivery.
Topics: Cell-Free System; Drug Delivery Systems; Molecular Chaperones; Protein Biosynthesis; Proteolipids
PubMed: 29625253
DOI: 10.1016/j.actbio.2018.03.043 -
Molekuliarnaia Biologiia 2021The mechanisms involved in the origin and development of malignant and neurodegenerative diseases are an important area of modern biomedicine. A crucial task is to...
The mechanisms involved in the origin and development of malignant and neurodegenerative diseases are an important area of modern biomedicine. A crucial task is to identify new molecular markers that are associated with rearrangements of intracellular signaling and can be used for prognosis and the development of effective treatment approaches. The proteolipid plasmolipin (PLLP) is a possible marker. PLLP is a main component of the myelin sheath and plays an important role in the development and normal function of the nervous system. PLLP is involved in intracellular transport, lipid raft formation, and Notch signaling. PLLP is presumably involved in various disorders, such as cancer, schizophrenia, Alzheimer's disease, and type 2 diabetes mellitus. PLLP and its homologs were identified as possible virus entry receptors. The review summarizes the data on the PLLP structure, normal functions, and role in diseases.
Topics: Diabetes Mellitus, Type 2; Humans; Myelin Sheath; Myelin and Lymphocyte-Associated Proteolipid Proteins; Nerve Tissue Proteins; Proteolipids
PubMed: 34837695
DOI: 10.31857/S0026898421060112 -
BMC Biology Feb 2024Membranes are protein and lipid structures that surround cells and other biological compartments. We present a conceptual model wherein all membranes are organized into...
Membranes are protein and lipid structures that surround cells and other biological compartments. We present a conceptual model wherein all membranes are organized into structural and functional zones. The assembly of zones such as receptor clusters, protein-coated pits, lamellipodia, cell junctions, and membrane fusion sites is explained to occur through a protein-lipid code. This challenges the theory that lipids sort proteins after forming stable membrane subregions independently of proteins.
Topics: Proteolipids; Membranes; Carrier Proteins; Cell Membrane
PubMed: 38414038
DOI: 10.1186/s12915-024-01849-6 -
Biochimica Et Biophysica Acta Nov 1998Pulmonary surfactant contains less than 1 wt% of the very non-polar surfactant protein C (SP-C). In most animal species the major form of SP-C is a 35-residue peptide... (Review)
Review
Pulmonary surfactant contains less than 1 wt% of the very non-polar surfactant protein C (SP-C). In most animal species the major form of SP-C is a 35-residue peptide chain which contains two thioester-linked palmitoyl groups, giving a total molecular mass of 4.2 kDa. Several minor variants of SP-C exist, formed from N-terminal truncation, lysine palmitoylation, methionine oxidation and C-terminal esterification. The primary structure is evolutionarily conserved and SP-C appears to be the only constituent which is unique to pulmonary surfactant, indicating important and specific functions. The three-dimensional structure in an aqueous mixed organic solvent determined by NMR spectroscopy revealed one continuous 37 A long alpha-helix encompassing residues 9-34 as the only regular structural element. The central 23 A of the helix contains exclusively aliphatic residues with branched side-chains, mainly valines, and exposes an all-hydrophobic regular surface. The size of the entire helix perfectly matches the thickness of a fluid dipalmitoylphosphatidylcholine membrane, and the all-hydrophobic part of the helix matches the acyl-chain part of such a bilayer. This supports a transmembrane orientation of SP-C in pulmonary surfactant bilayers. In a phospholipid monolayer, the SP-C helix is tilted, thereby maximizing the interactions with the lipid acyl-chains also in this environment. The palmitoylcysteines of SP-C, which are located in the flexibly disordered N-terminal octapeptide segment, appear to be important both for integrity of the alpha-helical structure and for functional properties. Since the conformation of the N-terminal part in a phospholipid environment is not known, the mechanisms whereby the SP-C thioester-linked palmitoyl chains affect structure and function remain to be determined.
Topics: Amino Acid Sequence; Molecular Sequence Data; Phospholipids; Protein Conformation; Protein Isoforms; Proteolipids; Pulmonary Surfactants; Structure-Activity Relationship
PubMed: 9813304
DOI: 10.1016/s0925-4439(98)00065-9 -
Pediatric Pathology & Molecular Medicine 2001Traditional thinking about surfactant proteins has centered around their effects on the biophysical properties of surfactant phospholipids. Accumulated data now suggests... (Review)
Review
Traditional thinking about surfactant proteins has centered around their effects on the biophysical properties of surfactant phospholipids. Accumulated data now suggests that the four major surfactant proteins (SPs) are a biochemically and functionally diverse group of mammalian peptides that have function beyond modification of alveolar surface tension. Alveolar SP-C (SP-C3.7, Mr 21,000) is 35 amino acid peptide isolated from lung surfactant that is synthesized and processed from a 191-197 amino acid precursor (proSP-C21). Although its solubility in organic solvents and avidity for lipid membranes impart properties important for its biophysical activity, SP-C represents a structurally and functionally challenging protein for the alveolar type II cell that must synthesize and traffic the peptide through the regulated secretory pathway. Despite technical and analytical difficulties imposed by its unique structure, our current understanding of SP-C biosynthesis has evolved over the past 10 years. Recent data now require us to consider proSP-C21 as a hybrid molecule incorporating structural and functional features both of bitopic integral membrane proteins as well us more classically recognized propeptide hormones. Our article highlights major developments related to characterization of molecular and cellular mechanisms underlying expression, post-translational processing, and targeting of proSP-C21 that result in production of secreted SP-C3.7.
Topics: Amino Acid Sequence; Animals; Biophysical Phenomena; Biophysics; Humans; Lung; Models, Biological; Molecular Sequence Data; Protein Processing, Post-Translational; Protein Structure, Secondary; Proteolipids; Pulmonary Surfactants; Sequence Homology, Amino Acid; Surface Tension
PubMed: 11699575
DOI: No ID Found -
Immunology Letters Mar 2008Toll-like receptor (TLR) signalling is initiated by the recruitment of one or more adaptor proteins to the activated receptor complex. At present, four of these proteins... (Review)
Review
Toll-like receptor (TLR) signalling is initiated by the recruitment of one or more adaptor proteins to the activated receptor complex. At present, four of these proteins are identified, namely MyD88, Mal, Trif and Tram and their selective usage by different TLRs in part accounts for TLR-specific transcriptional responses. Recent findings described unique biochemical properties for each of these TIR-domain containing adaptors and revealed that these adapters are subjected to post-translational modification. We used mammalian protein-protein interaction trap (MAPPIT), a two-hybrid technique that functions in a mammalian cell context, to study the molecular interactions downstream of TLR activation. We demonstrate pathway walking from TLR4 to IRAK-1 and identified Mal as a bridging adaptor, linking MyD88 to the activated TLR4.
Topics: Adaptor Proteins, Signal Transducing; Animals; Humans; Membrane Transport Proteins; Myelin Proteins; Myelin and Lymphocyte-Associated Proteolipid Proteins; Myeloid Differentiation Factor 88; Proteolipids; Signal Transduction; Toll-Like Receptors; Two-Hybrid System Techniques
PubMed: 18221795
DOI: 10.1016/j.imlet.2007.11.026 -
Biochimica Et Biophysica Acta.... Apr 2024The proteolipid code determines how cytosolic proteins find and remodel membrane surfaces. Here, we investigate how this process works with sorting nexins Snx1 and Snx3.... (Review)
Review
The proteolipid code determines how cytosolic proteins find and remodel membrane surfaces. Here, we investigate how this process works with sorting nexins Snx1 and Snx3. Both proteins form sorting machines by recognizing membrane zones enriched in phosphatidylinositol 3-phosphate (PI3P), phosphatidylserine (PS) and cholesterol. This co-localized combination forms a unique "lipid codon" or lipidon that we propose is responsible for endosomal targeting, as revealed by structures and interactions of their PX domain-based readers. We outline a membrane recognition and remodeling mechanism for Snx1 and Snx3 involving this code element alongside transmembrane pH gradients, dipole moment-guided docking and specific protein-protein interactions. This generates an initial membrane-protein assembly (memtein) that then recruits retromer and additional PX proteins to recruit cell surface receptors for sorting to the trans-Golgi network (TGN), lysosome and plasma membranes. Post-translational modification (PTM) networks appear to regulate how the sorting machines form and operate at each level. The commonalities and differences between these sorting nexins show how the proteolipid code orchestrates parallel flows of molecular information from ribosome emergence to organelle genesis, and illuminates a universally applicable model of the membrane.
Topics: Carrier Proteins; Vesicular Transport Proteins; Sorting Nexins; Protein Transport; Proteolipids
PubMed: 38408696
DOI: 10.1016/j.bbamem.2024.184305 -
Molecular Genetics and Metabolism Aug 1998Pulmonary surfactant, a complex mixture of phospholipids and specific associated proteins, reduces the surface tension at the air-liquid interface of the distal... (Review)
Review
Pulmonary surfactant, a complex mixture of phospholipids and specific associated proteins, reduces the surface tension at the air-liquid interface of the distal conducting airways and gas exchanging alveoli of the lung. Lipids, primarily neutral and phospholipids, compose approximately 90% of the surfactant complex. The remaining 10% of surfactant is composed of at least three surfactant-specific proteins, designated surfactant protein A (SP-A), SP-B, and SP-C. These proteins contribute to the formation, stabilization, and function of organized surfactant structures. This article briefly reviews the normal composition and function of pulmonary surfactant and specifically reviews the structure, function, and regulation of surfactant protein B (SP-B). The recent identification of neonates with refractory respiratory failure due to a genetic absence of SP-B and the study of transgenic mice in which SP-B gene expression has been ablated highlight the importance of the protein to surfactant function, synthesis, and metabolism and to the maintenance of lung function. Gene reconstitution experiments in vitro and in SP-B-deficient transgenic mice suggest specific functions for the amino and carboxyl terminal domains of the protein. SP-B deficiency is a potential target for gene therapy in human patients.
Topics: Amino Acid Sequence; Animals; Gene Expression Regulation; Humans; Mice; Mice, Transgenic; Molecular Sequence Data; Protein Processing, Post-Translational; Proteolipids; Pulmonary Surfactants; Structure-Activity Relationship
PubMed: 9758711
DOI: 10.1006/mgme.1998.2722 -
Neurochemical Research Aug 1994
Review
Topics: Animals; Humans; Lipid Bilayers; Membrane Proteins; Myelin and Lymphocyte-Associated Proteolipid Proteins; Nerve Tissue Proteins; Phylogeny; Proteolipids; Structure-Activity Relationship
PubMed: 7800123
DOI: 10.1007/BF00968705 -
The American Review of Respiratory... Oct 1990
Topics: Animals; Proteolipids; Pulmonary Surfactant-Associated Proteins; Pulmonary Surfactants
PubMed: 2221577
DOI: 10.1164/ajrccm/142.4.749