Molecular characterization, immune responsive expression and functional analysis of QM, a putative tumor suppressor gene from the Pacific white shrimp, Litopenaeus vannamei.
The QM, firstly identified as a putative tumor suppressor gene from human, has been confirmed to possess varieties of functions in a range of organisms. In the present study, the cDNA that encodes a 220-amino-acid QM protein with calculated molecular mass of 25.5 kDa and isoelectric point of 10.07 was characterized from the Pacific white shrimp Litopenaeus vannamei. Analysis of the deduced amino acid sequence of LvQM revealed that it contained a series of conserved functional motifs. Quantitative real-time PCR (qRT-PCR) results showed that the transcript of LvQM was extensively distributed in the tissues under investigation and most highly expressed in gill. After challenged with Vibrio anguillarum, the LvQM transcripts were significantly increased (P < 0.05) both in hepatopancreas and hemocytes in the early experimental phase. When LvQM was knocked down by RNA interference (RNAi), the transcript of prophenoloxidase (proPO) and the phenoloxidase activity (PO) in shrimp hemolymph were dramatically decreased, while the mortality was significantly increased. Furthermore, the recombinant LvQM protein (rLvQM) was successfully expressed in Escherichia coli BL21 (DE3)-pLysS. Injecting the purified rLvQM mixed with V. anguillarum markedly increased the clearance rate of bacteria and PO activity in the shrimp hemolymph. Hence, we conclude that LvQM was involved in the host defense of L. vannamei, probably as a positive regulator to phenoloxidase activity.
College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 Shaanxi, China.
Yongjie
Y
Liu
College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 Shaanxi, China.
Zhaoying
Z
Qian
College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 Shaanxi, China.
Rongfeng
R
Qu
College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 Shaanxi, China.
Xianzong
X
Wang
College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 Shaanxi, China.
Shulin
S
He
College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 Shaanxi, China.
Fujun
F
Hou
College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 Shaanxi, China.
Qiao
Q
Liu
College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 Shaanxi, China.
Xiao
X
Mi
College of Animal Science and Technology, Northwest A&F University, Yangling, 712100 Shaanxi, China. Electronic address: liuxiaolin@nwsuaf.edu.cn.
Xiaolin
X
Liu
D000818:Animals; D003001:Cloning, Molecular; D019295:Computational Biology; D017931:DNA Primers / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics; D004926:Escherichia coli; D005786:Gene Expression Regulation / Q000276:immunology*; D005880:Gills / Q000378:metabolism*; D006434:Hemocytes / Q000378:metabolism; D043143:Hepatopancreas / Q000378:metabolism; D014442:Monophenol Monooxygenase / Q000378:metabolism*; D033561:Penaeidae / Q000235:genetics* / Q000276:immunology; D034622:RNA Interference; D060888:Real-Time Polymerase Chain Reaction; D000080882:Ribosomal Protein L10; D012269:Ribosomal Proteins / Q000235:genetics* / Q000276:immunology; D014733:Vibrio / Q000276:immunology*
D017931:DNA Primers; D018076:DNA, Complementary; C000630686:RPL10 protein, human; D012269:Ribosomal Proteins; D014442:Monophenol Monooxygenase
Bacterial clearance; Litopenaeus vannamei; Phenoloxidase activity; QM; RNA interference