Zhi-Qiang Du

Inner Mongolia University of Science and Technology, Pao-t’ou, Inner Mongolia, China

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Publications (7)18.8 Total impact

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    ABSTRACT: Peroxinectin (PX) with cell adhesion and peroxidase activities is important in invertebrate immune responses. We identified a novel PX homolog from Scylla paramamosain (designated as Sp-PX) through transcriptome sequencing. The full-length of cDNA sequence was 3,165 bp. And there was a peroxidase domain in the deduced protein sequence. A cell-adhesive sequence (KGD motif) was also found in the N-terminus. The predicted molecular mass of the mature protein is 83.9 kDa, with an estimated pI of 6.21. At the amino acid level, Sp-PX shared much higher similarities with other crustaceans PX proteins. And Sp-PX also exhibited some similarities with other peroxidase family members. According to real-time polymerase chain reaction, Sp-PX was mainly distributed in the hemocytes. The gene expression levels in the hemocytes of the normal and white spot syndrome virus (WSSV)-challenged crabs were compared via high-throughput RNA sequencing technology, and the results showed that Sp-PX was upregulated at 48 h post-WSSV challenge. Subsequently, how Sp-PX responds to WSSV stimulus was explored through time-course experiments. The Sp-PX transcripts dramatically increased and reached the highest level at 12 h post-injection, whereas Sp-PX transcripts were recovered at 96 h post-challenge. Meanwhile, it was found that the WSSV copies proliferated significantly after a period of latent viral infection for 48 h. In addition,Sp-PX transcripts were also upregulated after Vibrio harveyi or Staphylococcus aureus challenge. Overall, Sp-PX not only participates in antibacterial immunity but also plays a crucial role in the antiviral immune responses of mud crab at the early stage of WSSV infection.
    Molecular Biology Reports 10/2013; · 2.51 Impact Factor
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    ABSTRACT: BAX inhibitor-1 (BI-1) was originally described as an anti-apoptotic protein in both animal and plant cells. BI-1 overexpression suppresses ER stress-induced apoptosis in animal cells. Inhibition of BI-1 activity could induce the cell death in mammals and plants. However, the function of BI-1 in crustacean immunity was unclear. In this paper, the full-length cDNA of a BI-1 protein in red swamp crayfish, Procambarus clarkii (PcBI-1) was cloned and its expression profiles in normal and infected crayfish were analyzed. The results showed that PcBI-1 was expressed in hemocytes, heart, hepatopancreas, gills, stomach, and intestines of the crayfish and was upregulated after challenged with Vibrio anguillarum and with white spot syndrome virus (WSSV). To determine the function of PcBI-1 in the innate immunity of the crayfish, the RNA interference against PcBI-1 was performed and the results indicated the hemocyte programmed cell death rate was increased significantly and WSSV replication was declined after PcBI-1 knocked down. Altogether, PcBI-1 plays an anti-apoptotic role, wherein high PcBI-1 expression suppresses programmed cell death, which is beneficial for WSSW replication in crayfish.
    Fish &amp Shellfish Immunology 04/2013; · 2.96 Impact Factor
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    ABSTRACT: Anti-lipopolysaccharide factors (ALFs) are a group of effector molecules that are classified as antimicrobial peptides (AMPs). They are found in limulids and crustaceans and show a broad range of antimicrobial activity. In the current study, an ALF gene from Macrobrachium rosenbergii (MrALF) was identified. Its full length was 690 bp and it encoded a 124 amino acid protein. A signal peptide and a conserved LPS-binding domain with two conserved cysteine residues that comprise a cluster of positive charged residues within a disulfide loop were predicted in MrALF. The M. rosenbergii ALF clusters with the Macrobrachium olfersii ALF and further clusters with most crustacean ALFs, suggesting that they should originate from one common ancestor. Positive selections should have sharpen the evolution of M. rosenbergii and M. olfersii ALF genes. Reverse transcriptase polymerase chain reaction analysis showed that MrALF was expressed in all detected tissues. In the epidermis, MrALF was obviously upregulated 24 h after the LPS challenge. In the stomach and gills, MrALF was upregulated upon LPS challenge. The results show that MrALF might have important roles in the immune defense against invading bacteria. The positive selections that occur in the ALFs of crustaceans might have resulted from a Red Queen's race with its pathogens. We found evidence of positive selection acting to drive functional divergence during the evolution crustacean ALF genes, especially in the M. rosenbergii ALF gene. The evolutionary changes might correspond to the challenges induced by pathogens that infect crustaceans.
    Molecular Biology Reports 02/2012; 39(7):7673-80. · 2.51 Impact Factor
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    ABSTRACT: In vertebrates, the globular "head" of complement component C1q receptor (gC1qR) is a versatile, multiligand binding protein. However, research on its function in invertebrates is limited. In the present study, a full-length cDNA sequence of a novel gC1qR homolog, FcgC1qR, from the Chinese white shrimp Fenneropenaeus chinensis was cloned. Semi-quantitative polymerase chain reaction (PCR) detected FcgC1qR in all examined tissues, with the highest level detected in the intestine. Western blot assay further revealed that the FcgC1qR protein was distributed in all tested tissues except the cell-free hemolymph of normal Chinese white shrimp. In the expression pattern study, quantitative real-time PCR demonstrated that the transcripts of FcgC1qR were up-regulated when challenged with bacteria (Vibrio anguillarum or Staphylococcus aureus) and white spot syndrome virus. Subsequently, FcgC1qR was over-expressed in Escherichia coli, and the polyclonal antibody was prepared with the purified recombinant protein. Microorganism binding was examined using Western blot assay, and revealed that FcgC1qR could bind to Bacillus cereus, Bacillus thuringiensis, S. aureus, V. anguillarum, Vibrioharveyi, and Candida albicans. FcgC1qR was also proven able to bind to S. aureus in a concentration-dependent manner, and this binding activity was partly inhibited by the polyclonal antibody. These results suggest that FcgC1qR may be involved in defending against bacterial infections in the Chinese white shrimp.
    Developmental and comparative immunology 08/2011; 36(2):400-7. · 3.29 Impact Factor
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    ABSTRACT: Single WAP domain-containing proteins (SWDs) are small proteins possessing a whey acidic protein (WAP) domain at the C-terminal region. In this study, a complementary deoxyribonucleic acid (cDNA) of SWD-containing protein was isolated from the hemocytes of red swamp crayfish, Procambarus clarkii called Pc-SWD. The full-length cDNA sequence is 998 bp. The deduced amino acid sequence consists of 74 residues with a signal peptide of 20 residues. The mature peptide has a single WAP domain which contains eight conserved cysteine residues forming a "four-disulphide core" (4-DSC). The predicted molecular mass of the mature protein is 5.97 kDa, with an estimated pI of 7.71. Tissue distribution analysis by reverse-transcribed polymerase chain reaction (RT-PCR) revealed that Pc-SWD transcripts were primarily found in the hemocytes, heart, hepatopancreas, gills, and intestine. The results of time course analysis demonstrated that expression of Pc-SWD was decreased at 6 h followed by a significant upregulation from 48 h to 72 h in hemocytes after white spot syndrome virus (WSSV) injection. A similar expression pattern was found in the hepatopancreas after WSSV injection. In addition, Pc-SWD expression was visibly upregulated in the gills from 6 h to 72 h after WSSV injection. The results of Western bolt revealed that Pc-SWD was constitutively expressed in the heart, hepatopancreas, gills, and intestine of unchallenged crayfish. A weak band was detected in the hemocytes and hemolymph of unchallenged P. clarkii. The Pc-SWD expression was upregulated in the hemocytes and gills after challenging with WSSV; however, no obvious change occurred in the heart and intestine. rPc-SWD could bind to both Gram-negative and -positive bacteria strongly. Moreover, rPc-SWD exhibited specific proteinase inhibitory activity against the secretory proteinase(s) from B. subtilis and P. aeruginosa. All these findings suggest that Pc-SWD possibly functions as an immunity effector in defense against the invasion of crayfish pathogens.
    Fish &amp Shellfish Immunology 10/2009; 28(1):134-42. · 2.96 Impact Factor
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    ABSTRACT: Acyl-CoA-binding protein (ACBP) and fatty acid-binding protein (FABP) are involved in lipid metabolism. ACBP plays a key role in multiple cellular tasks including modulation of fatty acid biosynthesis, enzyme regulation, vesicular trafficking, and gene regulation. In our study, a 536 bp cDNA of ACBP (FcACBP) was cloned and identified as a widely distributed gene in the Chinese white shrimp, Fenneropenaeus chinensis. Its expression in intestine was upregulated in response to white spot syndrome virus (WSSV) or Vibrio anguillarum infection. The expression patterns were confirmed by Western blot analysis. FABPs, members of the lipid-binding protein superfamily, play an important role in lipid metabolism and also participate in vertebrate innate immunity. A cDNA of FABP (FcFABP) cloned from the hepatopancreas of the shrimp was 715 bp in size and encoded a 14 kDa protein. FcFABP appeared to be a basic fatty acid binding protein with a predicted isoelectric point of 9.16. It showed sequence similarity to both vertebrate and invertebrate FABPs. Phylogenetic analysis showed that FcFABP, together with LvFABP, were clustered into one group. FcFABP was detected mainly in the hepatopancreas and expression level increased after a challenge with WSSV. FcFABP was down-regulated by V. anguillarum challenge. The protein also had bacterial binding activity. These two lipid metabolism related proteins may play important roles in shrimp innate immunity.
    Fish &amp Shellfish Immunology 09/2009; 27(6):739-47. · 2.96 Impact Factor
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    ABSTRACT: The whey major component, whey acidic protein (WAP), has one or more WAP domains characterized by a four-disulfide core (4-DSC) structure. These kinds of proteins are involved in multiple functions, including proteinase inhibitor activity, antimicrobial activity, ATPase inhibitor activity, and regulatory function in cell proliferation. Recent research indicates that WAP domain-containing proteins play an important role in the innate immunity of crustaceans. In this study, a novel double WAP domain (DWD)-containing protein named Fc-DWD was found for the first time in Chinese white shrimp, Fenneropenaeus chinensis. The open reading frame of Fc-DWD encodes a protein of 117 amino acids, including a signal peptide of 16 amino acids and two WAP domains. The predicted molecular mass of the mature protein is 12.78kDa with an estimated pI of 8.49. The first WAP domain, named WAP 1, composed of 49 amino acids locates in the amino-terminal of Fc-DWD, and the second WAP domain, named WAP 2, composed of 45 amino acids locates in the carboxy-terminal. Fc-DWD mRNA was upregulated in hemocytes, hepatopancreas, gills, and stomach of bacteria- and virus-challenged shrimp. Results of the binding assay showed that rFc-DWD could bind to both Gram-negative bacteria and Gram-positive bacteria. rWAP 1 could only bind to Gram-positive bacteria, but rWAP 2 could bind to both Gram-negative and positive bacteria. Moreover, rFc-DWD exhibited proteinase inhibitory activity against the secretory proteinase(s) from Bacillussubtilis and Pseudomonas aeruginosa. All of these findings suggest that Fc-DWD may play an important role in enabling the host defense to execute its proteinase inhibitory activity against pathogens.
    Comparative biochemistry and physiology. Part B, Biochemistry & molecular biology 07/2009; 154(2):203-10. · 1.61 Impact Factor

Publication Stats

38 Citations
18.80 Total Impact Points

Institutions

  • 2012–2013
    • Inner Mongolia University of Science and Technology
      Pao-t’ou, Inner Mongolia, China
  • 2009–2013
    • Shandong University
      • School of Life Science
      Chi-nan-shih, Shandong Sheng, China