Proteinase activated-receptors-associated signaling in the control of gastric cancer

Gastric cancer(GC)is the fourth most common cancer in the world and the second cause of cancer-related death.Gastric carcinogenesis is a multifactorial process,in which environmental and genetic factors interact to activate multiple intracellular signals thus leading to uncontrolled growth and survival of GC cells.One such a pathway is regulated by proteinase activated-receptors(PARs),seven transmembrane-spanning domain G protein-coupled receptors,which comprise four receptors(i.e.,PAR-1,PAR-2,PAR-3,and PAR-4)activated by various proteases.Both PAR-1 and PAR-2 are over-expressed on GC cells and their activation triggers and/or amplifies intracellular pathways,which sustain gastric carcinogenesis.There is also evidence that expression of either PAR-1 or PAR-2 correlates with depth of wall invasion and metastatic dissemination and inversely with the overall survival of patients.Consistently,data emerging from experimental models of GC suggest that both these receptors can be important targets for therapeutic interventions in GC patients.In contrast,PAR-4levels are down-regulated in GC and correlate inversely with the aggressiveness of GC,thus suggesting a negative role of this receptor in the control of GC.In this article we review the available data on the expression and role of PARs in GC and discuss whether manipulation of PAR-driven signals may be useful for interfering with GC cell behavior.

Polymorphisms of clip domain serine proteinase and serine proteinase homolog in the swimming crab Portunus trituberculatus andtheir associationwith Vibrio alginolyticus

Clip domain serine proteases （cSPs） and their homologs （SPHs） play an important role in various biological processes that are essential components of extracellular signaling cascades, especially in the innate immune responses of invertebrates. Here, polymorphisms of PtcSP and PtSPH from the swimming crab Portunus tritubereulatus were investigated to explore their association with resistance/ susceptibility to Vibrio alginolyticus. Polymorphic loci were identified using Clustal X, and characterized with SPSS 16.0 software, and then the significance of genotype and allele frequencies between resistant and susceptible stocks was determined by a Zz test. A total of 109 and 77 single nucleotide polymorphisms （SNPs） were identified in the genomic fragments of PtcSP and PtSPH, respectively. Notably, nearly half of PtSPH polymorphisms were found in the non-coding exon 1. Fourteen SNPs investigated were significantly associated with susceptibility/resistance to I1. alginolyticus （P〈0.05）. Among them, eight SNPs were observed in introns, and one synonymous, four non-synonymous SNPs and one ins-del were found in coding exons. In addition, five simple sequence repeats （SSRs） were detected in intron 3 of PtcSP. Although there was no statistically significant difference of allele frequencies, the SSRs showed different polymorphic alleles on the basis of the repeat number between resistant and susceptible stocks. After fiarther validation, polymorphisms investigated here might be applied to select potential molecular markers ofP. trituberculatus with resistance to I1. alginolyticus.

Effects of Feed-grade Proteinase on the Production Performance of Piglets

In this study, feed-grade proteinase was added into conventional diets of three-line crossbred （Duroc x Landrace x Large White） piglets, to investigate the effects of feed-grade proteinase on anti-diarrhea capacity, daily weight gain, feed intake and feed conversion ratio of piglets. The results showed that adding feed-grade proteinase in diets enhanced anti-diarrhea capacity of piglets and improved signifi- cantly production performance and breeding efficiency of piglets. This study provided the reference for rational utilization of feed-grade proteinase in actual production.

番木瓜proteinase omega基因启动子的克隆及功能初步研究

采用PCR技术从番木瓜基因组中克隆了proteinase omega基因的部分序列及其5′侧翼序列。序列分析表明,克隆到的基因序列与GenBank中的序列同源性为96%,长1039bp的5′端侧翼序列在GenBank数据库中没有同源片段。预测5′端侧翼序列有两处基础启动子区域,转录起始位点(TSS)分别为是A,T。在基础启动子区域都存在TATA-box,上游发现多处CAAT-box,G-box,I-box等顺式作用元件和AT富含区。构建了植物表达载体并用基因枪轰击番木瓜的叶组织,GUS基因瞬间表达结果表明,该长1039bp的5′端侧翼序列具有驱动GUS基因在乳管中表达的功能。该启动子的发现对进一步研究启动子的功能和开发番木瓜作为生物反应器具有重要意义。

A Proteinase from Mung Bean Sprouts That Inactivaties Soybean Trypsin Inhibitor

By 30% - 60% (NH4)(2)SO4 fractional precipitation, anion-exchange chromatography on DEAE-Sepharose CL-6B, gel filtration on Sephacryl S-200 and anion-exchange chromatography on Waters AP-1 column (Protein(PM)-Pak DEAE 15HR), a proteinase which can inactivate soybean trypsin inhibitor (STI) was purified from mung bean ( Vigna rabiata (L.) Wilezek) sprouts. Its molecular weight was estimated to be 29.8 kD by SDS-PAGE, and its K-m and V-max for STI were 769.2 N-alpha -benzoyl-L-arginine ethyl ester BAEE/mL and 115.3 BAEE . mL(-1) . min(-1) respectively. This proteinase was stable at temperatures lower than 50 degreesC and pH 6.5 - 8.5, and 90.91% STI activity of defatted soybean powder was inactivated by this preparation, with proteolytic activity 5 000 BAEE/mL at 50 degreesC and pH 8.0 in 4 h.

Potato Y Potyvirus Helper Component Proteinase Enhances Long-distance Movement of Potato X Potexvirus

To mutagenize two conserved CCCT and PTK motifs in the central domain of Chinese strain of potato Y potyvirus (PVY-C) helper component proteinase (HC-Pro), four mutants of HC-Pro gene were obtained by PCR and site-directed mutagenesis, and then were inserted into the constitutive expression vector pBin438. Leaves from tobacco (Nicotiana tabacum L. cv. K326) were transformed with these four plant expression plasmids by Agrobacterium-mediated transformation, respectively. Southern and Western blotting analyses showed that these four mutants were integrated into tobacco genomic DNA and could express the corresponding proteins in most of die transgenic plants. The challenge of transgenic plants with potato X potexvirus (PVX) revealed that the expression products of PVY-C HC-Pro mutants in transgenic plants greatly abolished functions of HC-Pro in enhancing the accumulation and pathogenicity of PVX, indicating that CCCT and PTK motifs of HC-Pro were required for PVX/PVY synergism. Meanwhile, the results demonstrated that PVY-C HC-Pro had a function in accelerating the long-distance movement of PVX in these transgenic plants for the first time.

Effects of proteinase A on cultivation and viability characteristics of industrial Saccharomyces cerevisiae WZ65

Proteinase A （PrA）, encoded by PEP4 gene, is a key enzyme in the vacuoles of Saccharomyces cerevisiae. We characterized the effects of PrA on cell growth and glucose metabolism in the industrial S. cerevisiae WZ65. It was observed that the lag phase of cell growth of partial PEP4 gene deletion mutant （36 h） and PrA-negative mutant （48 h） was significantly extended, compared with the wild type strain （24 h） （P〈0.05）, but PrA had no effect on glucose metabolism either under shaking or steady state cultivations. The logistic model was chosen to evaluate the effect of PrA on S. cerevisiae cell growth, and PrA was found to promote cell growth against insufficient oxygen condition in steady state cultivation, but had no effect in shaking cultivation. The effects of glucose starvation on cell growth of partial PEP4 gene deletion strain and PrA-negative mutant were also evaluated. The results show that PrA partial deficiency increased the adaption ofS. cerevisiae to unfavorable nutrient environment, but had no effect on glucose metabolism under the stress of low glucose. During heat shock test, at 60 ℃ the reduced cell viability rate （RCVR） was 10% for the wild type S. cerevisiae and 90% for both mutant strains （P〈0.01）, suggesting that PrA was a negative factor for S. cerevisiae cells to survive under heat shock. As temperatures rose from 60 ℃ to 70℃, the wild type S. cerevisiae had significantly lower relative glucose consumption rate （RGCR） （61.0% and 80.0%） than the partial mutant （78.0% and 98.5%） and the complete mutant （80.0% and 98.0%） （P〈0.05）, suggesting that, in coping with heat shock, cells of the PrA mutants increased their glucose consumption to survive. The present study may provide meaningful information for brewing industry; however, the role of PrA in industrial S. cerevisiae physiology is complex and needs to be further investigated.

Purification and Characterization of a Cathepsin B-Like Proteinase from Eggs of Antheraea Pernyi

A cathepsin B-like proteinase was purified from eggs of Antheraea pernyi by 5 steps of purification. The molecular mass of the proteinase are estimated to be 47 kDa by using SDS-polyacrylamide gel electro-phoresis. The activity of the purified proteinase were strongly inhibited by E-64 and Leupeptin. The optimum pH is 3.5 as determined by using the bovine hemo-globin as substrate. The activity and quantity of the proteinase during embryo development were studied. The results suggested that the proteolytic activities during embryo development at least partially came from this proteinase.

Heat shock induction of a 65 kDa ATP-binding proteinase in rat C6 glioma cells

The 45, 55, 65 and 100 kDa ATP-binding proteinases (ATP-BPases) of the heat-shocked (44 ℃ for 30 min, recovery for 12h) rat C6 glioma cells were purified by DEAE-ionexchange and ATP-affinity chromatography. Their molecular masses, isoelectric points (pI), pH-optima and other properties were analyzed by native proteinase gels.It was shown that the 65 kDa ATP-BPase is specifically induced by heat shock and not detectable in control cells.Its N-terminal 1-9 amino acid sequence was determined by Edman degradation, but no homologies to other proteins in the protein data bases were found. 30 and 31 kDa proteinases can be cleaved from the 45, 55 and 65 kDa proteinases to which they are linked. A possible relationship of the heat-induced 65 kDa ATP-BPase with the ATP-dependent proteinases (ATP-DPases) in prokaryotes and eukaryotes is discussed.

The RACE amplifying and sequence analyzing of secreted aspartic proteinase gene SA76 of Trichoderma harzianum

Total RNA was isolated from mycelium of T. harzianum by Total RNA extraction kit, and two clear bands of rRNA （28S and 18S） were observed in agarose electrophoresis. By joining the 3＇end sequence with the known SA76 EST from cDNA library of T. harzianum, a full-length cDNA sequence of 2019bp was obtained, whose open reading frame contained 1593bp, a stop codon TAA, a 5＇untranslated region （5＇UTR） of 266bp, a 3＇untranslated region （3＇UTR） of 201bp, and poly （A） 29 encoded a protein of 530 amino acids, had a signal peptide. T. harzianum shared 53% identity of secreted aspartic proteinase gene with G. zeae, 37% with N. crassa and 36% with C. globosum. The full-length cDNA sequence of secreted aspartic proteinase gene from T. harzianum was cloned for the first time by using BD SMART RACE technique, which provides a foundation to obtain and validate functional genes of T. harzianum.

Role of saliva proteinase 3 in dental caries

Salivary analysis can be used to assess the severity of caries. Of the known salivary proteins, a paucity of information exists concerning the role of proteinase 3（PR3）, a serine protease of the chymotrypsin family, in dental caries. Whole, unstimulated saliva was collected from children with varying degrees of active caries and tested using a Human Protease Array Kit and an enzyme-linked immunosorbent assay.A significantly decreased concentration of salivary PR3 was noted with increasing severity of dental caries（P,0.01）; a positive correlation（r50.87; P,0.01; Pearson’s correlation analysis） was also observed between salivary p H and PR3 concentration. In an antibacterial test,a PR3 concentration of 250 ng？m L21 or higher significantly inhibited Streptococcus mutans UA159 growth after 12 h of incubation（P,0.05）. These studies indicate that PR3 is a salivary factor associated with the severity of dental caries, as suggested by the negative relationship between salivary PR3 concentration and the severity of caries as well as the susceptibility of S. mutans to PR3.

Successive digestion of tilapia collagen by serine proteinase and proline specific endopeptidase to produce novel angiotensin l-converting enzyme inhibitory peptides

Serine proteinase,purified from the hepatopancreas of Pacific white shrimp(Litopenaeus vannamei), was used to hydrolyze acid solubilized collagen(ASC)isolated from Nile tilapia(Oreochromis sp.)skin to produce angiotensin I-converting enzyme(ACE)inhibitory peptides(ACEIPs).A series of column chromatography assays were used to separate the ACEIPs.A peptide,NPARTCR,was isolated as it exhibited high ACE inhibition potential.Further digestion of this peptide by a proline specific endopeptidase(PSEP),produced a pentapeptide ARTCR with ACE inhibitory activity(IC_(50))of 77.0 pmol/L.Both NPARTCR and ARTCR inhibited ACE in a non-competitive manner.An in vivo study in rats demonstrated that ARTCR has ACE inhibitory activity via lowering systolic blood pressure in spontaneously hypertensive rats(SHRs).These results suggest that processing by-products from shrimp and tilapia are ideal raw materials for the production of serine proteinase and collagen,respectively.Serine proteinase and collagen are both ideal raw materials that can be used to derive ACE inhibitory active peptides against hypertension.

GhWRKY75 positively regulates GhPR6-5b via binding to a W-box TTGAC(C/T)to orchestrate cotton resistance to Verticillium dahliae

Verticillium dahliae is an important fungal pathogen affecting cotton yield and quality.Therefore,the mining of V.dahlia-resistance genes is urgently needed.Proteases and protease inhibitors play crucial roles in plant defense responses.However,the functions and regulatory mechanisms of the protease inhibitor PR6 gene family remain largely unknown.This study provides a comprehensive analysis of the PR6 gene family in the cotton genome.We performed genome-wide identification and functional characterization of the cotton GhPR6 gene family,which belongs to the potato protease inhibitor I family of inhibitors.Thirty-nine PR6s were identified in Gossypium arboreum,G.raimondii,G.barbadense,and G.hirsutum,and they were clustered into four groups.Based on the analysis of pathogen-induced and Ghlmm transcriptome data,Gh PR6-5b was identified as the key gene for V.dahliae resistance.Virus-induced gene silencing experiments revealed that cotton was more sensitive to V.dahliae V991after PR6-5b silencing.The present study established that GhWRKY75 plays an important role in resistance to Verticillium wilt in cotton by positively regulating GhPR6-5b expression by directly binding to the W-box TTGAC(T/C).Our findings established that GhWRKY75 is a potential candidate for improving cotton resistance to V.dahliae,and provide primary information for further investigations and the development of specific strategies to bolster the defense mechanisms of cotton against V.dahliae.

NMR studies of the interaction between Bacillis subtilis neutral proteinase and inorganic metal compounds

The interaction between Bacillis subtilis neutral proteinase (B.S.NP) and inorganic metal compounds (CoCI2, NiCI2) was investigated by 1H NMR spectroscopy. It has been shown that the Zn(Ⅱ) ion in the active center of the native enzyme may directly interact with external CoCI2 and NiCI2, producing Co(Ⅱ)- and Ni(Ⅱ)-substituted derivatives, and their 1H NMR spectra were obtained for the first time. From the 1H NMR spectra, the coordinated structure of the active center in the native enzyme was described.

Correlation of Inhibitor Proteinase in Varieties and Lines of Cotton(Gossypium hirsutum L.) to Different Geographic Population of Verticillium dathliae Klebahn

Breeding for wilt resistance and its theoretical basis are primarily responsible for increases in cotton yield and fiber quality. Breeding for immunity is the most efficient method in our struggle with infectious diseases.

Molecular Cloning of a Thiol Proteinase Inhibitor Gene and Its Expression in E.coli

A cDNA library was constructed with 1.5×10~6 pfu from rice immature seeds,fromwhich a cDNA clone for rice thiol proteinase inhibitor,oryzacystatin(OC),was isolated byscreening with synthesized oligodeoxynucleotide probe,which contained a 309bp open read-ing frame,84bp 5′-end noncoding region and a poly(A)signal AATAAA at the 3′-end fol-lowed by 31Nt poly(A).Then the coding region of OC was amplified and inserted into thedownstream of λP_RP_L promoter for thermal-inducible expression in E.coli.Shifting the cul-ture temperature from 30℃ to 42℃ led to a high level expression of OC,which exhibited adistinct band of 12.0 kDa and accounted for at least 10% of the total soluble proteins fromSDS-PAGE.The papain-inhibitory activity of the expressed OC was further confirmed.

On the Activities of Pancreatic Proteases and Alpha-1 Proteinase Inhibitor in Meat-Type Chicken

The study was aimed at the evaluation of the effects of breed, age, different digestion stimulators, and dietary crude protein (CP) level on the activities of proteolytic enzymes in pancreatic tissue and duodenal chymus (in vivo), serum trypsin and α1-proteinase inhibitor (A1PI) concentrations in meat-type chicks. The study of age dynamics of trypsin and A1PI concentrations was performed on the chicks of hybrid cross “Smena-8”and two parental lines (Plymouth Rock and Cornish) fed standard commercial corn-wheat-SBM diets. Twenty birds per breed were euthanized at 1, 7, 14, 21, 28 and 35 days of age to obtain blood samples and pancreatic homogenate. Experiments on the effects of different digestion promotors (probiotic, acidifier, phytobiotic, enzymatic preparation) and different CP levels (finisher diet, CP 20%, vs. ground corn, CP 8.5%) were performed on 12 hybrid chicks with fistulated duodenum from 14 to 50 days of age. The following conclusions were made: 1) At 1 day of age high proteolytic activity in pancreatic tissue and maximal serum concentrations of trypsin and A1PI were found in both hybrid and parental lines. Since 7 to 35 days of age A1PI concentration was nearly constant, serum trypsin concentration decreased while proteolytic activity in pancreatic tissue exhibited undulate increase;2) Proteolytic activity in pancreatic tissue was higher in hybrids compared to the parental lines from 7 to 35 days of age (p 0.05);3) Supplementation of diet with exogenous enzymes stimulated the digestion due to the increase in protease activity in duodenal chymus by 9.1% compared to unsupplemented control (p 0.05);4) Proteolytic activity in duodenal chymus significantly responded to the substitution of ground corn for the complete diet by 2-fold decrease while serum trypsin concentration responded by 2.5-fold increase (p 0.001). This fact can indicate that physiological functions of digestive proteases are not confined to the digestive processes.

Expression of Candida Albicans Secreted Aspartyl Proteinase in Acute Vaginal Candidiasis

In order to analyze the in vivo expression of Candida albicans secreted aspartyl pro- teinases (SAP) in human vaginal infection, the vaginal secretion from 29 human subjects was col- lected by vaginal swab, and the expression of SAP1–SAP6 was detected by reverse-transcriptase po- lymerase chain reaction using specific primer sets. It was found that Sap2 and Sap5 were the most common genes expressed during infection; Sap3 and Sap4 were detected in all subjects and all 6 SAP genes were simultaneously expressed in some patients with vaginal candidiasis. It was suggested that the SAP family is expressed by Candida albicans during infection in human and that Candida albi- cans infection is associated with the differential expression of individual SAP genes which may be involved in the pathogenesis of vaginal candidiasis.

Cloning and Sequence Analysis of a Cysteine Proteinase Inhibitor Gene from Seedless Litchi

[Objective] This study aimed to clone and analyze the cysteine proteinase inhibitor gene from seedless litchi. [Method] According to the EST se- quence of cysteine proteinase inhibitor in constructed SSH snhtraetive library of seedless litchi abortion, nucleotide sequence of the cysteine proteinase inhibitor gene was obtained by using RACE technology and analyzed by using bioinformatics software. [ Result ] A cysteine protease inhibitor gene was obtained with the sequence of 635 bp containing a 321 bp open reading frame. It was predicted that the erlcoded protein contained 106 amino acids with conserved domain of cysteine proteinase inhibitor and had relatively high homology with the cysteine proteinase inhibitor gene of several species, [ Conclusion] This study laid the foundation for further ex- ploring the physiological functions of this cysteine proteinase inhibitor gene in plants.

Studies on Introduction of Arrowhead Proteinase Inhibitor Gene into N． tobacco Protoplasts

The Arrowhead Proteinase Inhibitor(API)gene was introduced into the protoplasts or mesophyll cells of N.tobacco by PEG-mediated.The transformed protoplasts undergoing dirrerentiation of callus and regeneration of plantlet have been growing into transgenic plants. Restriction endonuclease analysis of products amplificated by PCR indicates the existence of the API gene in the transformed plantlet.The extract of the leaves from the transformed plants shows trypsin inhibitory activity,which indicates the expression of the introduced API gene and the transformed plants can accumulate the inhibitor. However, the variation of the inhlbitory activity of the transformed plants reveals the importance of the integration site of the API gene in the genome.