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Human, rat, and mouse C-reactive protein (CRP) possess distinct expression patterns, but have similar conformations and conserved in vivo functions. We have previously demonstrated that this level-function mismatch is delicately tuned by the hidden activities of unfolded CRP. The cholesterol-binding sequence (CBS; a.a. 35-47) is a major functional motif exposed on monomeric CRP, which is the unfolded and activated conformation of CRP. We replaced the CBS of rat CRP with that of either mouse or human CRP, yielding two grafting mutants with unaffected pentameric assembly. However, these mutants exhibited altered cellular foldability and conformational activation efficiency that matched those of the CRP that provided the grafted CBS. These results indicate that CBS is a critical regulatory motif, whose variation maintains the pentameric assembly of CRP but derives distinct cellular foldabilities and conformational activation efficiencies, therefore helping to ensure that CRPs with various expression patterns exhibit overall conserved functions.

C-reactive protein (CRP) can exist in both pentameric (pCRP) and monomeric conformation (mCRP). Though serum pCRP is an established marker of inflammation, the diagnostic significance of mCRP remains unknown largely due to the lack of a reliable assay. The power and specificity of antibody-based assays are limited by the antibody reagents used and by the degree of cross-reactivity that may exist in detecting each antigen, as mCRP is known to be formed from the pentameric and both conformations usually coexist in clinical samples. Here, we describe an assay that measures both CRP conformations in simple samples in a single assay. This assay depends on the rationale that the intra-molecular disulfide bonds in pCRP resist reduction, while those in mCRP can be readily reduced. The distinct sensitivity of pCRP and mCRP to reduction can be easily detected and separated by electrophoresis. This assay may provide a means to study clinical correlation between pCRP and mCRP in clinical samples in the future and to evaluate their respective significance as disease markers.

Amyloid‐β peptides (Aβs) are generated in a membrane‐embedded state by sequential processing of amyloid precursor protein (APP). Although shedding of membrane‐embedded Aβ is essential for its secretion and neurotoxicity, the mechanism behind shedding regulation is not fully elucidated. Thus, we devised a Langmuir film balance‐based assay to uncover this mechanism. We found that Aβ shedding was enhanced under acidic pH conditions and in lipid compositions resembling raft microdomains, which are directly related to the microenvironment of Aβ generation. Furthermore, Aβ shedding efficiency was determined by the length of the C‐terminal membrane‐spanning region, whereas pH responsiveness appears to depend on the N‐terminal ectodomain. These findings indicate that Aβ shedding may be directly coupled to its generation and represents an unrecognized control mechanism regulating the fate of membrane‐embedded products of APP processing.

C-reactive protein (CRP) is an acute phase reactant secreted by hepatocytes as a pentamer. The structure formation of pentameric CRP has been demonstrated to proceed in a stepwise manner in live cells. Here, we further dissect the sequence determinants that underlie the key steps in cellular folding and assembly of CRP. The initial folding of CRP subunits depends on a leading sequence with a conserved dipeptide that licenses the formation of the hydrophobic core. This drives the bonding of the intra-subunit disulfide requiring a favorable niche largely conferred by a single residue within the C-terminal helix. A conserved salt bridge then mediates the assembly of folded subunits into pentamer. The pentameric assembly harbors a pronounced plasticity in inter-subunit interactions, which may form the basis for a reversible activation of CRP in inflammation. These results provide insights into how sequence constraints are evolved to dictate structure and function of CRP.

Prostate cancer is one of the leading causes of cancer death for male. In the present study, we applied an integrated bioinformatics approach to provide a novel perspective and identified some hub genes of prostate cancer. Microarray data of fifty-nine prostate cancer were downloaded from Gene Expression Omnibus. Gene Ontology and pathway analysis were applied for differentially expressed genes between high and low grade prostate cancer. Weighted gene coexpression network analysis was applied to construct gene network and classify genes into different modules. The most related module to high grade prostate cancer was identified and hub genes in the module were revealed. Ingenuity pathway analysis was applied to check the chosen module’s relationship to high grade prostate cancer. Hub gene’s expression profile was verified with clinical samples and a dataset from The Cancer Genome Atlas project. 3193 differentially expressed genes were filtered and gene ontology and pathway analysis revealed some cancer- and sex hormone-related results. Weighted gene coexpression network was constructed and genes were classified into six modules. The red module was selected and ingenuity pathway analysis confirmed its relationship with high grade prostate cancer. Hub genes were identified and their expression profile was also confirmed. The present study applied integrate bioinformatics approaches to generate a holistic view of high grade prostate cancer and identified hub genes could serve as prognosis markers and potential treatment targets.

Recent studies have reported the association between endothelial nitric oxide synthase (eNOS) gene G894T polymorphism and pregnancy-induced hypertension (PIH). However, the results have been inconsistent. We conducted a comprehensive meta-analysis to explore this association. A total of 36 case-control studies involving 4028 PIH cases and 7672 controls were ultimately included. In the overall analysis, no association was identified between eNOS gene G894T polymorphism and PIH risk in any of the genetic models. In the subgroup analysis, the results showed that T-allele carriers had a higher risk of PIH than those with the G allele in Asians (G vs. T: odds ratio (OR)=0.76, 95% confidence interval (CI)=0.63-0.91, P=0.002; GT+TT vs. GG: OR=1.32, 95% CI=1.09-1.59, P=0.004; TT vs. GT+GG: OR=1.96, 95% CI=1.26-3.06, P=0.003; TT vs. GG: OR=1.99, 95% CI=1.27-3.11, P=0.003; GT vs. GG: OR=1.23, 95% CI=1.05-1.43, P=0.009). For Latin American and African populations, the association between G894T polymorphism and susceptibility to PIH was only observed in the dominant model. However, no association was observed in Europeans and Americans. Therefore, eNOS gene G894T polymorphism was related to PIH risk, especially for Asians.

Prostate cancer (PCa) is one of the most commonly diagnosed urological malignancies. However, there are limited therapies for PCa patients who develop biochemical recurrence after androgen deprivation therapy (ADT). In the present study, we investigated the therapeutic efficacy and mechanism of α-Viniferin (KCV), an oligostilbene of trimeric resveratrol, against human PCa cells and found that it markedly inhibited the proliferation of LNCaP, DU145, and PC-3 cancer cells in a time- and dose-dependent manner, and had a strong cytotoxicity in non-androgen-dependent PCa cells. In addition, KCV inhibited AR downstream expression in LNCaP cells, and inhibited activation of GR signaling pathway in DU145 and PC-3. Further investigation indicated that KCV could induce cancer cell apoptosis through AMPK-mediated activation of autophagy, and inhibited GR expression in castration-resistant prostate cancer(CRPC). These findings suggest that KCV may prove to be a novel and effective therapeutic agent for the treatment of CRPC.

The conformational conversion of pentameric C-reactive protein (pCRP) to monomeric CRP (mCRP) has been shown to play important roles in the action of CRP in inflammation regulation. In vivo studies revealed the origin of mCRP and provided insights into how pCRP dissociation affected its functions. However, the interplay and exact bioactivities of CRP isoforms still remain uncertain due to the rapid conformational conversion and complex milieu in vivo. Herein, we have used surface-immobilization of pCRP to generate a preservable intermediate with dual antigenicity expression of both pCRP and mCRP. The intermediate has been further shown to exhibit modified bioactivities, such as a high affinity with solution-phase pCRP and an enhanced capacity of complement interaction. These results thus not only provide the conformational conversion details of CRP, but also propose a simple way in vitro to study how the functions of CRP are tuned by distinct isoforms.