Collagen Sequence Research Articles

Retendo (mucopolygen complex) effects on achille tendon healing

IntroductionThe injuries of achilles tendon which is among the most important tendons in the body include many problems. Limited tendon recovery is provided through the surgical procedures available. Re-rupture occurs during and after recovery and the long time it takes to return to work, impossibility of early movement of the affected ankle and not being able to provide a physiological recovery in tendon constitute a problem. Thus, our objective in this study was to demonstrate the recovery effects of Retendon (mucopolygen complex) on achilles tendon. Material-methodAfter taking the consent of the ethics board we applied for animal experiments, the experiment animals in our study were separated into two groups as those which were given Retendo® (Mucopolygen Complex - Mucopolysaccharides, Hydrolyzed Collagen Type I, Vitamin C) and the control group. These two groups were separated into four groups. In a total of eight groups, 40 female Wistar-Albino rats with an average weight of 200–350 gr. were included in the study. ResultsThe study had biomechanical and histological results. While there was no significant difference in vascularization, inflamation and fibroblastic level among the groups in histological terms, collagen formation was detected to be more regular in the experiment group than the control group. A significant efficiency couldn't be acquired in biomechanical terms. DiscussionAlthough Retendo® (mucopolygen complex) is commonly used in muscle and tendon diseases, its effect mechanism is not definitely known. But in the light of the findings we acquired in our study, we detected that Retendo® (mucopolygen complex) applied after achilles tendon ruptures positively effected collagen sequencing during recovery in histological terms but didn't have a significant effect on the mean load achilles tendon can tolerate before rupturing.

Disulfide Crosslinked Hydrogels Made From the Hydra Stinging Cell Protein, Minicollagen-1.

Minicollagens from cnidarian nematocysts are attractive potential building blocks for the creation of strong, lightweight and tough polymeric materials with the potential for dynamic and reconfigurable crosslinking to modulate functionality. In this study, the Hydra magnipapillata minicollagen-1 isoform was recombinantly expressed in bacteria, and a high throughput purification protocol was developed to generate milligram levels of pure protein without column chromatography. The resulting minicollagen-1 preparation demonstrated spectral properties similar to those observed with collagen and polyproline sequences as well as the ability to self-assemble into oriented fibers and bundles. Photo-crosslinking with Ru(II) was used to create robust hydrogels that were analyzed by mechanical testing. Interestingly, the minicollagen-1 hydrogels could be dissolved with reducing agents, indicating that ruthenium-mediated photo-crosslinking was able to induce disulfide metathesis to create the hydrogels. Together, this work is an important first step in creating minicollagen-based materials whose properties can be manipulated through static and reconfigurable post-translational modifications.

Collagen-like sequences encoded by extremophilic and extremotolerant bacteria

Collagens and collagen-like proteins are found in a wide range of organisms. The common feature of these proteins is a triple helix fold, requiring a characteristic pattern of amino acid sequences, composed of Gly-X-Y tripeptide repeats. Collagen-like proteins from bacteria are heterogeneous in terms of length and amino acid composition of their collagenous sequences. However, different bacteria live in different environments, some at extreme temperatures and conditions. This study explores the occurrence of collagen-like sequences in the genomes of different extreme condition-adapted bacteria, and investigates features that could be linked to conditions where they thrive. Our results show that proteins containing collagen-like sequences are encoded by genomes of various extremophiles. Some of these proteins contain conservative domains, characteristic of cell or endospore surface proteins, while most other proteins are unknown. The characteristics of collagenous sequences may depend on both, the phylogenetic relationship and the living conditions of the bacteria.

Species identification of Late Pleistocene bat bones using collagen fingerprinting

AbstractBats form the second most diverse mammalian order (Chiroptera), after rodents, and vary widely in their physiology and ecology. Those species that live in temperate climates are generally insectivorous and nocturnal or crepuscular, sheltering in tree hollows, caves, or buildings during the day. They are potentially valuable ecological indicators, due to their dependence on suitable roosting sites and arthropod food, both of which are commonly affected by human activities. Identification of bats from ancient assemblages that are found in caves could therefore provide useful data for palaeoenvironmental reconstructions and show the effect of habitat loss. Here, we apply the recently developed approach of collagen fingerprinting by soft ionisation mass spectrometry to the identification of ancient bat remains in an archaeological assemblage from Pin Hole Cave (Derbyshire, England). Our results show that a simple set of markers can distinguish all seven genera of bats known to be present in either modern or ancient Britain (Myotis, Nyctalus, Pipistrellus, Barbastella, Plecotus, Eptesicus, and Rhinolophus). Further analysis indicates that species‐level determination is possible in some of these taxa, but it would more readily be achieved using the more advanced methods of collagen sequence analysis by liquid chromatography coupled with tandem mass spectrometry. Within our assemblage yielding ~6,800 ancient bone collagen fingerprints, we identified only ~1% that derived from chiropterans, and these were predominantly derived from Myotis (two apparent Brandt's bat fingerprints but the majority indistinguishable between the whiskered, Daubenton's and Natterer's bats), Barbastella (the western barbastelle being the only member of this genus known within Europe), and Rhinolophus (identified as the lesser horsehoe bat R. hipposideros rather than the rare greater horseshoe bat R. ferrumequinum). We infer that the site was likely used by roosting bats throughout the year, and the accumulation of these remains was probably not the result of predator activity. More importantly, the peptide biomarkers provided here could proove valuable in the more systematic analysis of microfaunal remains across many European archaeological and palaeontological sites, preferably those that are collected with well curated stratigraphical information and chronological frameworks.

A molecular phylogeny of the extinct South American gomphothere through collagen sequence analysis

The extant elephants are only a small fraction of the diverse order of proboscideans that once roamed the planet, whereas the extinct gomphotheres represent the largest and most diverse of these enigmatic groups that survived into the Quaternary. However, their relationship to the living elephantids and the other extinct elephantiformes, such as the mastodons, remains debated. To begin to address this we have used proteomic analysis to sequence the collagen surviving in sub-fossil Notiomastodon bone from the site of Pilauco in Chile. Through the genus-level information retrieved, phylogenetic analyses of the near-complete (85–90%) sequences that were recovered surprisingly revealed a closer relationship between the South American gomphothere (Notiomastodon) and the American mastodon (Mammut) than to the elephantids (Loxodonta, Elephas and Mammuthus), as most commonly proposed; a finding that was consistent across all phylogenetic analyses used, including bayesian, parsimony and máximum likelihood approaches. These results demonstrate the potential information that can be recovered using the ever-increasing applications of proteomics to palaeobiology, particularly for improving our understanding of the evolution of extinct species in a manner consistent with the latest DNA-based approaches.

Imaging diagnosis for intervertebral disc.

Various functional magnetic resonance imaging (MRI) techniques have been investigated in recent years and are being used in clinical practice for the patients with low back pain (LBP). MRI is an important modality for diagnosing intervertebral disc (IVD) degeneration. In recent years, there have been several reported attempts to use MRI T2 mapping and MRI T1ρ mapping to quantify lumbar disc degeneration. MRI T2 mapping involves digitizing water content, proteoglycan content, and collagen sequence breakdown as relaxation times (T2 values) at each site. These digitized values are used to create a map, that is, then used to quantitatively evaluate the metabolite concentrations within IVD tissues. MRI T2 mapping utilizes the T2 relaxation time to quantify moisture content and the collagen sequence breakdown. MRI T1ρ mapping digitizes water molecule dispersion within the cartilaginous matrix to evaluate the degree of cartilaginous degeneration. Magnetic resonance spectroscopy is a less‐invasive diagnostic test that provides biochemical information. Adequate analysis of the IVD has not yet been performed, although there are indications of a relationship between the adipose content of the multifidus muscle in the low back and LBP. The ultra short TE technique has been recently used to investigate lumbar cartilaginous endplates. Unlike diagnosis based on contrast‐enhanced images of the IVD, which depends on the recurrence of pain that is determined subjectively, MRI‐based diagnosis is less‐invasive and based on objective imaging findings. It is therefore expected to play a key role in the diagnostic imaging of IVD conditions in the future.

Molecular underpinnings of integrin binding to collagen-mimetic peptides containing vascular Ehlers–Danlos syndrome–associated substitutions

Collagens carry out critical extracellular matrix (ECM) functions by interacting with numerous cell receptors and ECM components. Single glycine substitutions in collagen III, which predominates in vascular walls, result in vascular Ehlers-Danlos syndrome (vEDS), leading to arterial, uterine, and intestinal rupture and an average life expectancy of <50 years. Collagen interactions with integrin α2β1 are vital for platelet adhesion and activation; however, how these interactions are impacted by vEDS-associated mutations and by specific amino acid substitutions is unclear. Here, we designed collagen-mimetic peptides (CMPs) with previously reported Gly → Xaa (Xaa = Ala, Arg, or Val) vEDS substitutions within a high-affinity integrin α2β1-binding motif, GROGER. We used these peptides to investigate, at atomic-level resolution, how these amino acid substitutions affect the collagen III-integrin α2β1 interaction. Using a multitiered approach combining biological adhesion assays, CD, NMR, and molecular dynamics (MD) simulations, we found that these substitutions differentially impede human mesenchymal stem cell spreading and integrin α2-inserted (α2I) domain binding to the CMPs and were associated with triple-helix destabilization. Although an Ala substitution locally destabilized hydrogen bonding and enhanced mobility, it did not significantly reduce the CMP-integrin interactions. MD simulations suggested that bulkier Gly → Xaa substitutions differentially disrupt the CMP-α2I interaction. The Gly → Arg substitution destabilized CMP-α2I side-chain interactions, and the Gly → Val change broke the essential Mg2+ coordination. The relationship between the loss of functional binding and the type of vEDS substitution provides a foundation for developing potential therapies for managing collagen disorders.

IN SILICO APPROACH OF COLLAGEN FROM TUNA FISH BY-PRODUCT AS ANGIOTENSIN-CONVERTING ENZYME INHIBITOR

Objective: This study explores the sustainable valorization of by-products from tuna fish based on in silico approach.&#x0D; Methods: In silico approaches (BIOPEP database, PeptideRanker database, peptide calculator [PepCalc] database, and toxin prediction [ToxinPred] database) were employed to evaluate the potential of collagens from tuna as a potential source of bioactive peptides. Furthermore, primary structure, biological potential, physicochemical, sensory, and toxicity characteristics of the theoretically released angiotensin-converting enzyme (ACE) inhibitor collagen peptides were predicted.&#x0D; Results: Tuna collagen was selected as a potential precursor of bioactive peptides based on in silico analysis. Most notable among these are ACE inhibitory peptides. First, the potential of tuna collagen for the releasing bioactive peptides was evaluated by determining the frequency of occurrence of fragments with a given activity. Through the BIOPEP database analysis, there are many bioactive peptides in tuna collagen sequences. Then, an in silico proteolysis using selected enzymes (papain and pepsin) to obtained ACE inhibitory peptides was investigated and then analyzed using PeptideRanker and PepCalc. Cytotoxicity analysis using the online toxic prediction tool ToxinPred revealed that all in silico proteolysis-derived ACE inhibitory peptides are non-cytotoxic.&#x0D; Conclusions: Overall, the present study highlights that the tuna collagens could be a promising precursor of bioactive peptides that have an antihypertensive effect (ACE inhibitory activities) for developing functional food or nutraceutical products.

Palaeoproteomics resolves sloth relationships.

The living tree sloths Choloepus and Bradypus are the only remaining members of Folivora, a major xenarthran radiation that occupied a wide range of habitats in many parts of the western hemisphere during the Cenozoic, including both continents and the West Indies. Ancient DNA evidence has played only a minor role in folivoran systematics, as most sloths lived in places not conducive to genomic preservation. Here we utilize collagen sequence information, both separately and in combination with published mitochondrial DNA evidence, to assess the relationships of tree sloths and their extinct relatives. Results from phylogenetic analysis of these datasets differ substantially from morphology-based concepts: Choloepus groups with Mylodontidae, not Megalonychidae; Bradypus and Megalonyx pair together as megatherioids, while monophyletic Antillean sloths may be sister to all other folivorans. Divergence estimates are consistent with fossil evidence for mid-Cenozoic presence of sloths in the West Indies and an early Miocene radiation in South America.

Computational design of heterotrimeric collagen helices

As an important biomedical material, collagen has been widely used in wound sutures, cartilage defect filling, and bone metal implant coating. Seven out of the twenty-eight types of natural collagen are heterotrimers comprising three chains with different primary sequences. It is important to understand the intermolecular forces underlying the hetero-specific assembly of natural collagen to modulate material properties in protein engineering and biomaterials engineering. Till date, the most important pairwise interaction identified in the collagen triple helix is the axial charge pair, which can be formed between appropriately placed lysine and aspartate or glutamate residues. These pairwise amino acid interactions enable the preparation of heterotrimeric helices with high specificity, as well as excellent control over helix structure and stability. Further, detailed studies on these interactions will allow the modification of natural collagen sequences to develop clean-sourced, highly controllable, and compositionally responsive collagen biomaterials. This review will summarize our understanding of this interaction and other charged-pair interactions and describe how they have been successfully used to control collagen triple helix self-assembly and explore new protein design strategies.

Analysis of Neuropathic Pain Using Magnetic Resonance Imaging T2 Mapping of Intervertebral Disc in Chronic Low Back Pain.

Study DesignCross sectional study.PurposeThe study aimed to analyze mechanisms underlying chronic low back pain (CLBP) using magnetic resonance imaging (MRI) T2 mapping of the intervertebral disc (IVD).Overview of LiteratureMRI T2 mapping utilizes the T2 values for quantifying moisture content and collagen sequence breakdown. We previously used MRI T2 mapping for quantifying the extent of IVD degeneration (IVDD) and showed a correlation between the degeneration of the posterior annulus fibrosus (AF) and CLBP.MethodsWe enrolled 40 patients with CLBP (17 males, 23 females; mean age, 50.8±1.6 years; range, 22–60 years). IVDs were categorized as the anterior AF, nucleus pulposus (NP), and posterior AF, and T2 value for each disc was measured. T2 values, assessed using the Japanese neuropathic pain (NeP) screening questionnaire, of the NeP and nociceptive pain (NocP) groups were compared.ResultsT2 values of the NocP and NeP groups were 64.7±5.6 ms and 58.1±2.3 ms for the anterior AF; 67.0±4.6 ms and 59.6±2.1 ms for NP; and 70.7±4.6 ms and 51.0±1.2 ms for the posterior AF, respectively. T2 values for IVDD were significantly lower in the NeP group than those in the NocP group (p<0.01).ConclusionsThe results indicate a correlation between the degeneration of posterior AF and NeP. MRI T2 mapping may be beneficial for detecting NeP caused by IVDD and can help formulate targeted analgesic therapies.

Detection of target collagen peptides with single amino acid mutation using two fluorescent peptide probes.

Collagen with a single amino acid substitution is the main cause of a plethora of heritable disorders such as Osteogenesis Imperfecta and Ehlers-Danlos syndrome. Though significant advances have been achieved in the development of protein assays, it remains very challenging to distinguish a protein with a single amino acid mutation from the wild-type protein. A novel fluorescent self-quenching assay has been constructed to detect target collagen peptides with a single amino acid mutation using two probe peptides. The hybridization of the probe peptide and the natural target collagen peptide results in a complete heterotrimer and strong fluorescence, whereas the mixture of the probe peptide and the mutation collagen sequences leads to a partial homotrimer and pronounced fluorescence self-quenching. The extent of fluorescence quenching is dependent on the identity of the residue replacing Gly following the order of Ala < Ser < Arg, while the Gly-Ala mutation causes the mildest fluorescence loss. The probe peptide-based fluorescence self-quenching assay facilitates specific detection of the target collagen sequence with a single Gly mutation at the nM level. The simultaneous utilization of both probe peptides enables efficient discrimination between different mutation peptides. To our knowledge, our work may be the first report of a robust analytical assay that can identify collagen fragments with single amino acid mutation, which will greatly contribute to deciphering the molecular mechanism of Osteogenesis Imperfecta as well as developing novel diagnostic strategies.

Collagen sequence analysis of fossil camels, Camelops and c.f. Paracamelus, from the Arctic and sub-Arctic of Plio-Pleistocene North America

Proteomic analyses of ancient remains are increasing in number and offer great potential to recover phylogenetic information on extinct animals beyond the reach of ancient DNA, but limitations in proteomic techniques remain unclear. Here we carry out LC-MS/MS sequence analysis of a ~3.5 million year old giant camel specimen from Nunavut along with the younger Pleistocene remains of the Yukon giant camel (c.f. Paracamelus) and the western camel (Camelops hesternus) for comparison with complete sequences to both extant camels (Bactrian and Dromedary) and the alpaca. Although not complete (~75–80% sequence coverage), no amino acid sequence differences were confidently observed between the giant camels and the extant Dromedary, indicative of a closer relationship than that of the extant Bactrian lineage. However, multiple amino acid changes were observed for the western camel (Camelops) collagen sequence, placing it as a sister group to these members of the Camelini tribe consistent recent ancient DNA analyses. Although this supports a role for the sequencing of ancient collagen in the understanding of vertebrate evolution, these analyses highlight the limitations in phylogenetic reconstructions based on partial sequence data retrieved from proteomic analyses, particularly, the impact of omitting even only a single peptide on the resulting tree topology. The presence of other non-collagenous proteins, such as biglycan and PEDF, indicates a further resource for phylogenetic information, but none more promising than the degraded camel albumin seemingly observed in the Pliocene specimen. SignificanceAs proteomics is becoming more frequently used in the study of ancient proteins, an emerging field known as ‘palaeoproteomics’ (or ‘paleoproteomics’), understanding the limitations of the technique is essential.Here, through the study of the oldest undisputed collagen sequences obtained from proteomics, we confirm that some peptides following diagenetic modifications of tryptic sites are no longer matched with standard searches, but can be matched with Error Tolerant searches.We also demonstrate the ability to retrieve phylogenetic information consistent with that of ancient DNA methods, but that with the omission of only one or more key peptides, the inferred evolutionary relationships change. This is a significant finding for the field of palaeoproteomics implying a need for better understanding the particular composition of the partial sequences retrieved from proteomic analyses.

Using a collagen heterotrimer to screen for cation-π interactions to stabilize triple helices

As one of non-covalent forces to stabilize protein, cation-π interactions in collagen have been received much attention. Three chains of collagen form its characteristic secondary structure, triple helices. Based on a collagen heterotrimer, abc, a library containing 15 mutant peptides was built to characterize the stabilizing effects of 24 pairwise cation-π interactions. The six stabilizing pairs, axial FK, YK, WK, RF, and RW, and lateral RF, have been identified, among which only axial RF frequently occurs in natural collagen sequences. This suggests that cation-π interactions might not be optimized in natural collagen.

Dissecting MMP P10′ and P11′ subsite sequence preferences, utilizing a positional scanning, combinatorial triple-helical peptide library

Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that remodel the extracellular matrix environment and mitigate outside-in signaling. Loss of regulation of MMP activity plays a role in numerous pathological states. In particular, aberrant collagenolysis affects tumor invasion and metastasis, osteoarthritis, and cardiovascular and neurodegenerative diseases. To evaluate the collagen sequence preferences of MMPs, a positional scanning synthetic combinatorial library was synthesized herein and was used to investigate the P10' and P11' substrate subsites. The scaffold for the library was a triple-helical peptide mimic of the MMP cleavage site in types I-III collagen. A FRET-based enzyme activity assay was used to evaluate the sequence preferences of eight MMPs. Deconvolution of the library data revealed distinct motifs for several MMPs and discrimination among closely related MMPs. On the basis of the screening results, several individual peptides were designed and evaluated. A triple-helical substrate incorporating Asp-Lys in the P10'-P11' subsites offered selectivity between MMP-14 and MMP-15, whereas Asp-Lys or Trp-Lys in these subsites discriminated between MMP-2 and MMP-9. Future screening of additional subsite positions will enable the design of selective triple-helical MMP probes that could be used for monitoring in vivo enzyme activity and enzyme-facilitated drug delivery. Furthermore, selective substrates could serve as the basis for the design of specific triple-helical peptide inhibitors targeting only those MMPs that play a detrimental role in a disease of interest.

Friday, September 28, 2018 1:00 PM–2:30 PM abstracts: a new look at imaging: 203. Analysis of chronic low back pain with magnetic resonance imaging T2 mapping of lumbar intervertebral disc

Friday, September 28, 2018 1:00 PM–2:30 PM abstracts: a new look at imaging: 203. Analysis of chronic low back pain with magnetic resonance imaging T2 mapping of lumbar intervertebral disc

Determination of the ingredients of horse, ox, sheep, pig, camel and deer skin in colla corii asini by ultra performance liquid chromatography-tandem mass spectrometry

A method was established for detecting the ingredients of horse, ox, sheep, pig, camel and deer skin in colla corii asini using ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS).Theoretical marker peptides were selected by comparing the collagen sequences in the skins of donkeys, horses, oxen, sheep, pigs, camels, and deer.Marker peptides were identified by protease cutting techniques and high resolution mass spectrometry and then analyzed by UPLC-MS/MS.The separation was performed on a UPLC system with a BEH C18 column via the gradient elution of acetonitrile containing 0.1%(v/v) acetic acid and water containing 0.1%(v/v) acetic acid.The marker peptides were identified in the modes of electrospray positive ionization (ESI+) and multiple reaction monitoring (MRM).The marker peptides for the horse, ox, sheep, pig and camel skin were detected in 15 samples.The method is simple, highly reproducible, and suitable for the identification of mixed skin ingredients in colla corii asini.It has been successfully used to detect the authenticity of colla corii asini.

Unique Conformation in a Natural Interruption Sequence of Type XIX Collagen Revealed by Its High-Resolution Crystal Structure.

Naturally occurring interruptions in nonfibrillar collagen play key roles in molecular flexibility, collagen degradation, and ligand binding. The structural feature of the interruption sequences and the molecular basis for their functions have not been well studied. Here, we focused on a G5G type natural interruption sequence G-POALO-G from human type XIX collagen, a homotrimer collagen, as this sequence possesses distinct properties compared with those of a pathological similar Gly mutation sequence in collagen mimic peptides. We determined the crystal structures of the host-guest peptide (GPO)3-GPOALO-(GPO)4 to 1.03 Å resolution in two crystal forms. In these structures, the interruption zone brings localized disruptions to the triple helix and introduces a light 6-8° bend with the same directional preference to the whole molecule, which may correspond structurally to the first physiological kink site in type XIX collagen. Furthermore, at the G5G interruption site, the presence of Ala and Leu residues, both with free N-H groups, allows the formation of more direct and water-mediated interchain hydrogen bonds than in the related Gly → Ala structure. These could partly explain the difference in thermal stability between the different interruptions. In addition, our structures provide a detailed view of the dynamic property of such an interrupted zone with respect to hydrogen bonding topology, torsion angles, and helical parameters. Our results, for the first time, also identified the binding of zinc to the end of the triple helix. These findings will shed light on how the interruption sequence influences the conformation of the collagen molecule and provide a structural basis for further functional studies.

Single-Molecule Assay for Proteolytic Susceptibility: Force-Induced Destabilization of Collagen's Triple Helix

Force plays a key role in regulating dynamics of biomolecular structure and interactions, yet techniques are lacking to manipulate and continuously read out this response with high throughput. We present an enzymatic assay for force-dependent accessibility of structure that makes use of a wireless Mini-Radio Centrifuge Force Microscope (MR.CFM) to provide a real-time readout of kinetics. The microscope is designed for ease of use, fits in a standard centrifuge bucket, and offers high-throughput, video-rate readout of individual proteolytic cleavage events. Proteolysis measurements on thousands of tethered collagen molecules were used to determine how the triple helix responds to force. As the primary load- and tension-bearing protein in vertebrates, the physical properties of collagen are of significant biomedical interest. How collagen's triple helix responds to applied force is controversial, with different studies inferring incompatible outcomes: overwinding, unwinding, shearing, or maintaining its zero-force structure. Because proteolytic cleavage requires a locally unwound triple helix, our experiments reveal how local collagen structure changes in response to applied force. Our first results show a load-enhanced trypsin sensitivity, indicating destabilization of the triple helix. The generality of this result will be discussed in the context of collagen's sequence heterogeneity.

Detection of substrate binding of a collagen-specific molecular chaperone HSP47 in solution using fluorescence correlation spectroscopy

Heat shock protein 47 kDa (HSP47), an ER-resident and collagen-specific molecular chaperone, recognizes collagenous hydrophobic amino acid sequences (Gly-Pro-Hyp) and assists in secretion of correctly folded collagen. Elevated collagen production is correlated with HSP47 expression in various diseases, including fibrosis and keloid. HSP47 knockdown ameliorates liver fibrosis by inhibiting collagen secretion, and inhibition of the interaction of HSP47 with procollagen also prevents collagen secretion. Therefore, a high-throughput system for screening of drugs capable of inhibiting the interaction between HSP47 and collagen would aid the development of novel therapies for fibrotic diseases. In this study, we established a straightforward method for rapidly and quantitatively measuring the interaction between HSP47 and collagen in solution using fluorescence correlation spectroscopy (FCS). The diffusion rate of HSP47 labeled with Alexa Fluor 488 (HSP47-AF), a green fluorescent dye, decreased upon addition of type I or III collagen, whereas that of dye-labeled protein disulfide isomerase (PDI) or bovine serum albumin (BSA) did not, indicating that specific binding of HSP47 to collagen could be detected using FCS. Using this method, we calculated the dissociation constant of the interaction between HSP47 and collagen. The binding ratio between HSP47-AF and collagen did not change in the presence of sodium chloride, confirming that the interaction was hydrophobic in nature. In addition, we observed dissociation of collagen from HSP47 at low pH and re-association after recovery to neutral pH. These observations indicate that this system is appropriate for detecting the interaction between HSP47 and collagen, and could be applied to high-throughput screening for drugs capable of suppressing and/or curing fibrosis.