Chordin Research Articles

The secreted protein FonCHRD is essential for vegetative growth, asexual reproduction, and pathogenicity in watermelon Fusarium wilt fungus

Fungal pathogens often secrete numerous effectors to interfere with and/or suppress plant immunity to promote their infection. Watermelon Fusarium wilt, caused by the soil-borne fungus Fusarium oxysporum f. sp. niveum (Fon), is one of the devastating diseases that severely affect the watermelon industry. Here, we report the function of a candidate effector protein, FonCHRD, in Fon. FonCHRD harbors a chordin (CHRD) domain of unknown function and has a signal peptide with secretion activity. FonCHRD shows a relatively high expression level in Fon marcoconidia and is inducible by watermelon root tissues. Phenotypic analysis of the targeted deletion mutant revealed that FonCHRD plays roles in vegetative growth, asexual reproduction, and conidial morphology of Fon, while it is not involved in spore germination as well as cell wall, oxidative and salt stress responses. Deletion of FonCHRD impaired the ability to colonize and spread within host plants, significantly reducing its virulence on watermelon. FonCHRD is distributed across multiple compartments of plant cells but can target to the apoplast space in plants. FonCHRD inhibits the INF1- and Bcl2-associated X protein-triggered cell death and defense gene expression in transiently expressed Nicotiana benthamiana leaves. These findings suggest that FonCHRD is essential for Fon pathogenicity by modulating invasive growth and spreading abilities as well as by suppressing plant immune responses.

Chord axial compressive behavior of hybrid FRP-concrete-steel double-skin tubular member T-joints

Hybrid fiber reinforced polymer (FRP)-concrete-steel double-skin tubular members (DSTMs) are a promising form of structural members with superior mechanical performance and durability, which have great potential for application in ocean structures. Such hybrid DSTMs consist of three components: an inner steel tube, an outer FRP tube, and concrete filled between the two tubes. Despite a significant number of studies demonstrating the excellent performance of hybrid DSTMs, no studies have been concerned with the joints of these members. The lack of a reliable design method for DSTM joints is certainly a huge obstacle to their wide application in practice. Against the above background, a research project has been proposed to understand the static behavior of circular DSTM T-joints through a combined experimental, modeling, and theoretical study. This paper presents the results of an experimental program on the axial compressive behavior of the chord in DSTM T-joints. The effects of various important factors, such as FRP tube thickness, steel tube thickness, brace-to-chord diameter ratio, void ratio, and concrete strength, on the performance of the DSTM T-joints were examined in detail. The test results demonstrated that the DSTM T-joints exhibited a ductile behavior provided that the joint region was appropriately strengthened and the presence of a brace did not significantly affect the compressive behavior of the chord in the joints with a brace-to-chord diameter ratio of 0.5. Finally, a simple method was proposed to predict the axial load-axial strain behavior of the DSTM T-joints.

The developmental gene Chordin is amplified and expressed in human cancers

ABSTRACT Chordin (CHRD) is a secreted protein important in early development, yet a role for CHRD in human disease has not been identified. In this study we investigated CHRD in cancer and normal adult tissues using the wealth of genome-wide data available in public databases. We found that Chordin is amplified in the DNA of specific cancers such as lung squamous cell and others, although copy number variation did not strictly correlate with higher mRNA expression. In some cancers, such as renal and stomach carcinomas, increased CHRD expression significantly correlated with poor survival. In normal adult human tissues, CHRD mRNA was highest in hepatocytes. Crossveinless-2/BMPER, a component of the Chordin morphogenetic pathway expressed at the opposite side in embryos, was expressed in liver stellate cells. This raises the intriguing possibility that a BMP gradient might be established in the extracellular matrix of the space of Disse that surrounds portal sinusoid capillaries.

Thymosin β4 Identified by Transcriptomic Analysis from HF Anagen to Telogen Promotes Proliferation of SHF-DPCs in Albas Cashmere Goat.

Increasing cashmere yield is one of the important goals of cashmere goat breeding. To achieve this goal, we screened the key genes that can improve cashmere performance. In this study, we used the RNA raw datasets of the skin and dermal papilla cells of secondary hair follicle (SHF-DPCs) samples of hair follicle (HF) anagen and telogen of Albas cashmere goats and identified a set of significant differentially expressed genes (DEGs). To explore potential associations between gene sets and SHF growth features and to identify candidate genes, we detected functional enrichment and constructed protein-protein interaction (PPI) networks. Through comprehensive analysis, we selected Thymosin β4 (Tβ4), Rho GTPase activating protein 6 (ARHGAP6), ADAM metallopeptidase with thrombospondin type 1 motif 15, (ADAMTS15), Chordin (CHRD), and SPARC (Osteonectin), cwcv and kazal-like domains proteoglycan 1 (SPOCK1) as candidate genes. Gene set enrichment analysis (GSEA) for these genes revealed Tβ4 and ARHGAP6 have a close association with the growth and development of SHF-DPCs. However, the expression of Tβ4 in the anagen was higher than that in the telogen, so we finally chose Tβ4 as the ultimate research object. Overexpressing Tβ4 promoted and silencing Tβ4 inhibited the proliferation of SHF-DPCs. These findings suggest that Tβ4 can promote the growth and development of SHF-DPCs and indicate that this molecule may be a valuable target for increasing cashmere production.

The BMP2 variant L51P restores the osteogenic differentiation of human mesenchymal stromal cells in the presence of intervertebral disc cells.

Spinal fusion is hampered by the presence of remaining intervertebral disc (IVD) tissue and leads to spinal non-union. While the exact mechanism remains unknown, we hypothesise that factors preventing disc ossification, such as antagonists of the bone morphogenetic proteins (BMP), could be responsible for this process. The objective of this study was to investigate spinal non-union using an in vitro human model with a focus on the BMP signalling components and to identify factors contributing to the incomplete and delayed ossification. Human bone marrow-derived mesenchymal stromal cells (MSC) were cocultured with IVD cells in the presence of L51P, a BMP2 variant with osteoinductive potential. The ossification of MSC was evaluated by quantitative reverse transcription polymerase chain reaction (qPCR), alkaline phosphatase (ALP) activity and alizarin red staining. Endogenous expression of major BMP antagonists, namely Gremlin (GREM1), Noggin (NOG) and Chordin (CHRD) was detected in IVD-derived cells, with abundance in nucleus pulposus cells. Osteogenesis of MSC was hindered by IVD cells as shown by reduced alizarin red staining, ALP activity and qPCR. L51P, added to the cocultures, restored mineralisation, blocking the activity of the BMP antagonists secreted by IVD cells. It is possible that the BMP antagonists secreted by IVD cells are responsible for spinal non-unions. The inhibition of BMP antagonists with L51P may result in an efficient and more physiological osteoinduction rather than delivery of exogenous osteogenic factors. Therefore, L51P might represent an attractive therapeutic candidate for bone healing.

Osteogenic differentiation of bone marrow stromal cells is hindered by the presence of intervertebral disc cells.

BackgroundClinical observations indicate that the presence of nucleus pulposus (NP) tissue during spinal fusion hinders the rate of disc ossification. While the underlying mechanism remains unknown, this observation could be due to incomplete removal of NP cells (NPCs) that secrete factors preventing disc calcification, such as bone morphogenetic protein (BMP) antagonists including noggin and members of the DAN (differential screening selected gene aberrative in neuroblastoma) family.MethodsMonolayer human bone marrow-derived mesenchymal stem cells (MSCs) were cocultured withNPCs and annulus fibrosus cells (AFCs) embedded in alginate for 21 days. At the end of coculture, MSCs were stained for mineral deposition by alizarin red, and relative expression of bone-related genes [Runt-related transcription factor 2, (RUNX2), Osteopontin (OPN), and Alkaline phosphatase (ALP)] and ALP activity were analyzed. Relative expression of three BMP antagonists, chordin (CHRD), gremlin (GREM1), and noggin (NOG), was determined in primary human NPCs and AFCs. These cells were also stained for Gremlin and Noggin by immunocytochemistry.ResultsAlizarin red staining showed that MSC osteogenesis in monolayer cultures was inhibited by coculture with NPCs or AFCs. ALP activity and RT-PCR analyses confirmed these results and demonstrated inhibition of osteogenesis of MSC in the presence of disc cells. NOG was significantly up-regulated in MSCs after coculture. Relative gene expression of intervertebral disc (IVD) cells showed higher expression of GREM1 in NPCs than in AFCs.ConclusionsWe show that primary IVD cells inhibit osteogenesis of MSCs. BMP inhibitors NOG, GREM1 and CHRD were expressed in IVD cells. GREM1 appears to be differentially expressed in NPCs and AFCs. Our results have implications for the design and development of treatments for non-union in spinal fusion.

Chordin is underexpressed in ovarian tumors and reduces tumor cell motility

Ovarian cancers mostly derive from the monolayer epithelium that covers the ovary. There are currently very few molecular clues to the etiology of this cancer. Bone morphogenetic proteins (BMPs) are required for follicular development and female fertility and are expressed in the ovarian surface epithelium (OSE). We previously reported the expression of human chordin (CHRD), a BMP extracellular regulator, in the ovary. Here we show that CHRD is underexpressed in epithelium ovary cancer and epithelial cancer cell lines as compared with normal tissues and OSE, respectively. Besides, we detected BMP expression in all ovarian cell lines analyzed. To determine the functional relevance of the absence of CHRD mRNA in tumors and cancer cell lines, we studied the effects of CHRD on two cancer cell lines, BG1 and PEO14. Migratory and invasive properties were greatly reduced, whereas cell adhesion to the support was enhanced. In addition, we detected chordin (Chrd) expression in OSE of rat ovaries in a pattern similar to that of BMP4. Altogether, these results suggest that CHRD could participate in regulating BMP activity in normal OSE physiology, and that its mis-expression in OSE may facilitate cancer incidence and/or progression.

The pro-BMP activity of Twisted gastrulation is independent of BMP binding.

The determination of the vertebrate dorsoventral body axis is regulated in the extracellular space by a system of interacting secreted molecules consisting of BMP, Chordin, Tolloid and Twisted Gastrulation (Tsg). Tsg is a BMP-binding protein that forms ternary complexes with BMP and Chordin. We investigated the function of Tsg in embryonic patterning by generating point mutations in its two conserved cysteine-rich domains. Surprisingly, Tsg proteins with mutations in the N-terminal domain were unable to bind BMP, yet ventralized the embryo very effectively, indicating strong pro-BMP activity. This hyperventralizing Tsg activity required an intact C-terminal domain and could block the anti-BMP activity of isolated BMP-binding modules of Chordin (CRs) in embryonic assays. This activity was specific for CR-containing proteins as it did not affect the dorsalizing effects of Noggin or dominant-negative BMP receptor. The ventralizing effects of the xTsg mutants were stronger than the effect of Chordin loss-of-function in Xenopus or zebrafish. The results suggest that xTsg interacts with additional CR-containing proteins that regulate dorsoventral development in embryos.

CHRD, a novel domain in the BMP inhibitor chordin, is also found in microbial proteins

CHRD (after SWISSPROT abbreviation for chordin) is a novel domain identified in chordin, an inhibitor of bone morphogenetic proteins. Database searches have revealed several microbial homologues to this domain. It is anticipated to have an immunoglobulin-like β-barrel structure based on limited similarity to superoxide dismutases but, as yet, no clear functional prediction can be made.

鋼管トラス節点弦材管の局部破壊に関する実験的研究 : その 2・圧縮支管と弦材管の交角および両支管の間隙変化の影響

鋼管トラス節点弦材管の局部破壊に関する実験的研究 : その 2・圧縮支管と弦材管の交角および両支管の間隙変化の影響