Cloning and Sequence Analysis of Prophenoloxidase from Haemocytes of the Red Swamp Crayfish, Procambarus clarkii

• Published in: Agricultural sciences in China Vol. 8; no. 3; pp. 369 - 379
• Main Authors: LI, Yan-he, ZHENG, Fang-liang, CHEN, Hong-quan, WANG, Han-zhong, WANG, Liu-quan, XU, Di-ping
• Format: Journal Article
• Language: English
• Published: Anhui Agricultural University, Hefei 230036, P.R.China 01.03.2009; The Fishery Institute, Anhui Academy of Agricultural Sciences, Hefei 230031, P.R.China%State Key Laboratory of Virology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, P.R.China%Anhui Agricultural University, Hefei 230036, P.R.China%The Fishery Institute, Anhui Academy of Agricultural Sciences, Hefei 230031, P.R.China%Huibei Key Laboratory of Animal Embryo & Molecular Breeding, Hubei Academy of Agricultural Sciences, Wuhan 430064, P.R.China
• Subjects: 克氏螯虾; 全长cDNA序列; 基因组DNA; 序列分析; 英国石油公司; nucleotide sequence; prophenoloxidase eDNA; intron; Procambarus clarkii; copper-binding sites
• ISSN: 1671-2927
• DOI: 10.1016/S1671-2927(08)60221-7

The full-length cDNA sequence of prophenoloxidase was obtained through RACE technology. The complete cDNA sequence is 3 721-bp long, containing an open reading frame （ORF） of 1 881 bp, a 154-bp 5′-untranslated region, and a 1 686- bp 3′-untranslated region with three potential functional poly（A） signals （AATAAA）. The molecular mass of the deduced amino acid sequence （627 aa） was 72.3 kDa with an estimatedpI of 5.88. It contained putative copper-binding sites （copper A： 131, 135, 167 and copper B： 301,305, 341）, and a tentative complement-like motif （GCGWPDHL）. Eight potential N-linked glycosylation sites were predicted to be present in P. clarkii prophenoloxidase. Similar to those in other arthropod prophenoloxidases reported so far, no signal peptide was detected in the crayfish prophenoloxidase. The phylogenetic trees confirmed that P. clarkii prophenoloxidase was most closely related to that of freshwater crayfish P. leniusculus and more closely related to other crustacean prophenoloxidases from shrimp, prawn, and lobster than to the insect prophenoloxidases. Besides, two putative introns were found in this sequence of genomic DNA.