Expression, purification and characterization of soluble recombinant periostin protein produced by Escherichia coli

Development of a one-shot dual aptamer-based fluorescence nanosensor for rapid, sensitive, and label-free detection of periostin

Periostin is associated with several diseases, including cancers. Therefore, monitoring blood periostin levels is a powerful tool for diagnosing various diseases and identifying their severity. However, conventional detection methods pose several challenges, including high costs. To address these issues, we developed a novel one-shot dual aptamer-based fluorescence nanosensor for detecting periostin. The proposed nanosensor facilitates rapid, label-free, and sensitive detection of periostin using gold nanoprobes constructed by rhodamine-b isothiocyanate, PL2trunc aptamer, and gold nanoparticles and silver nanoprobes fabricated by the PL5trunc aptamer and silver nanoparticles. The two nanoprobes form a core-satellite structure by interacting with periostin, and the nanosensor detects periostin through the fluorescence regenerated by the increased proximity between them. The nanosensor successfully detected periostin with remarkable detection limits of 106.68 pM in buffer and 463.3 pM in serum-spiked conditions within 30 min without additional washing or signal amplification processes. Considering serum periostin levels in various diseases, the proposed nanosensor provides a suitable method for identifying patients with various diseases and determining disease severity. Moreover, the platform can be helpful as a practical method for on-site medical diagnosis because it can be adapted to detect other biomarkers simply by replacing the aptamer with other detection probes.

Periostin and its interacting proteins in the construction of extracellular architectures

Periostin is a matricellular protein that is composed of a multi-domain structure with an amino-terminal EMI domain, a tandem repeat of four FAS 1 domains, and a carboxyl-terminal domain. These distinct domains have been demonstrated to bind to many proteins including extracellular matrix proteins (Collagen type I and V, fibronectin, tenascin, and laminin), matricellular proteins (CCN3 and βig-h3), and enzymes that catalyze covalent crosslinking between extracellular matrix proteins (lysyl oxidase and BMP-1). Adjacent binding sites on periostin have been suggested to put the interacting proteins in close proximity, promoting intermolecular interactions between each protein, and leading to their assembly into extracellular architectures. These extracellular architectures determine the mechanochemical properties of connective tissues, in which periostin plays an important role in physiological homeostasis and disease progression. In this review, we introduce the proteins that interact with periostin, and discuss how the multi-domain structure of periostin functions as a scaffold for the assembly of interacting proteins, and how it underlies construction of highly sophisticated extracellular architectures.

Periostin function in communication with extracellular matrices

Periostin is a secretory protein with a multi-domain structure, comprising an amino-terminal cysteine-rich EMI domain, four internal FAS 1 domains, and a carboxyl-terminal hydrophilic domain. These adjacent domains bind to extracellular matrix proteins (type I collagen, fibronectin, tenascin-C, and laminin γ2), and BMP-1 that catalyzes crosslinking of type I collagen, and proteoglycans, which play a role in cell adhesion. The binding sites on periostin have been demonstrated to contribute to the mechanical strength of connective tissues, enhancing intermolecular interactions in close proximity and their assembly into extracellular matrix architectures, where periostin plays further essential roles in physiological maintenance and pathological progression. Furthermore, periostin also binds to Notch 1 and CCN3, which have functions in maintenance of stemness, thus opening up a new field of periostin action.

Periostin Deficiency Causes Severe and Lethal Lung Injury in Mice With Bleomycin Administration

Pulmonary capillary leakage followed by influx of blood fluid into the air space of lung alveoli is a crucial step in the progression of acute lung injury (ALI). This influx is due to increased permeability of the alveolar-capillary barrier. The extracellular matrix (ECM) between the capillary and the epithelium would be expected to be involved in prevention of the influx; however, the role of the ECM remains to be addressed. Here, we show that the ECM architecture organized by periostin, a matricellular protein, plays a pivotal role in the survival of bleomycin-exposed mice. Periostin was localized in the alveolar walls. Although periostin-null mice displayed no significant difference in lung histology and air-blood permeability, they exhibited early lethality in a model of bleomycin-induced lung injury, compared with their wild-type counterparts. This early lethality may have been due to increased pulmonary leakage of blood fluid into the air space in the bleomycin-exposed periostin-null mice. These results suggest that periostin in the ECM architecture prevents pulmonary leakage of blood fluid, thus increasing the survival rate in mice with ALI. Thus, this study provides an evidence for the protective role of the ECM architecture in the lung alveoli.

Periostin promotes secretion of fibronectin from the endoplasmic reticulum

Extracellular matrix (ECM) proteins are synthesized in the endoplasmic reticulum (ER), transported to the extracellular milieu through the secretory pathway, and assembled into an extracellular architecture. A previous study of ours showed that periostin, a secretory protein, interacts with fibronectin and is involved in ECM remodeling. Here we show that periostin played a role in fibronectin secretion from the ER. Co-immunoprecipitation and in situ proximity ligation assays revealed an interaction between periostin and fibronectin in the ER. Although accumulation of fibronectin was detected in the ER of fibroblastic C3H10T1/2 cells, forced expression of periostin in those cells decreased the accumulation of fibronectin in the ER, suggesting that periostin promoted the secretion of fibronectin. A substitution mutant of tryptophan at the position 65 to alanine in the EMI domain of periostin, which caused periostin to lose its ability to interact with fibronectin, did not decrease the accumulation. Furthermore, targeted disruption of periostin in mice caused the non-fibrillar and ectopic deposition of fibronectin in the periodontal ligament. Thus, these results demonstrate a subcellular role of periostin in promotion of fibronectin secretion from the ER.

Periostin in fibrillogenesis for tissue regeneration: periostin actions inside and outside the cell

More than 10 years have passed since the naming of periostin derived from its expression sites in the periosteum and periodontal ligament. Following this finding, we have accumulated more data on the expression patterns of periostin, and, finally, with the generation of periostin-deficient mice, have revealed functions of periostin in the regeneration of tissues in bone, tooth, heart, and skin, and its action in cancer invasion. Since periostin is a matricellular protein, the first investigation of periostin function showed its enhancement of cell migration by acting outside the cell. On the other hand, recent observations have demonstrated that periostin functions in fibrillogenesis in association with extracellular matrix molecules inside the cell.

Interaction between periostin and BMP-1 promotes proteolytic activation of lysyl oxidase

Intra- and intermolecular covalent cross-linking between collagen fibrils, catalyzed by lysyl oxidase (LOX), determines the mechanical properties of connective tissues; however, mechanisms that regulate the collagen cross-linking according to tissue specificity are not well understood. Here we show that periostin, a secretory protein in the dense connective tissues, promotes the activation of LOX. Previous studies showed that periostin null mice exhibit reduced collagen cross-linking in their femurs, periosteum, infarcted myocardium, and tendons. Presently, we showed that active LOX protein, formed by cleavage of its propeptide by bone morphogenetic protein-1 (BMP-1), was decreased in calvarial osteoblast cells derived from periostin null mice. Overexpression of periostin promoted the proteolytic cleavage of the propeptide, which increased the amount of active LOX protein. The results of co-immunoprecipitation and solid phase binding assays revealed that periostin interacted with BMP-1. Furthermore, this interaction probably resulted in enhanced deposition of BMP-1 on the extracellular matrix, suggesting that this enhanced deposition would lead to cleavage of the propeptide of LOX. Thus, we demonstrated that periostin supported BMP-1-mediated proteolytic activation of LOX on the extracellular matrix, which promoted collagen cross-linking.

Incorporation of tenascin-C into the extracellular matrix by periostin underlies an extracellular meshwork architecture

Extracellular matrix (ECM) underlies a complicated multicellular architecture that is subjected to significant forces from mechanical environment. Although various components of the ECM have been enumerated, mechanisms that evolve the sophisticated ECM architecture remain to be addressed. Here we show that periostin, a matricellular protein, promotes incorporation of tenascin-C into the ECM and organizes a meshwork architecture of the ECM. We found that both periostin null mice and tenascin-C null mice exhibited a similar phenotype, confined tibial periostitis, which possibly corresponds to medial tibial stress syndrome in human sports injuries. Periostin possessed adjacent domains that bind to tenascin-C and the other ECM protein: fibronectin and type I collagen, respectively. These adjacent domains functioned as a bridge between tenascin-C and the ECM, which increased deposition of tenascin-C on the ECM. The deposition of hexabrachions of tenascin-C may stabilize bifurcations of the ECM fibrils, which is integrated into the extracellular meshwork architecture. This study suggests a role for periostin in adaptation of the ECM architecture in the mechanical environment.