title: Molecular cloning and phylogenetic analysis on alpha2-macroglobulin (alpha2-M) of white shrimp Litopenaeus vannamei.
abstract: The full-length sequence of alpha2-macroglobulin (alpha2-M) was cloned from the hemocytes of white shrimp Litopenaeus vannamei by reverse transcription polymerase chain reaction (RT-PCR), cloning and sequencing of overlapping PCR, and the rapid amplification of cDNA ends method. The alpha2-M cDNA consists of 4682bp with an open reading frame of 4479bp, a 52-bp 5'-untranslated region, and a 132-bp 3'-untranslated region. The predicted molecular mass of the mature protein (1475 amino acids) is 167.1kDa, with an estimated pI of 5.70. The L. vannamei alpha2-M sequence contains putative functional domains including a bait region, a GCGEQNM (985-991) thiol ester domain, and a receptor-binding domain. Sequence comparison and phylogenetic analyses show that alpha2-M deduced amino acid sequence of L. vannamei has a high level of similarity to that of tiger shrimp Penaeus monodon and kuruma shrimp Marsupenaeus japonicus. The alpha2-M transcript was mainly expressed in hemocytes, and was significantly higher in premoult stage than in intermoult and postmoult stages.
authors: Department of Aquaculture, College of Life Sciences, National Taiwan Ocean University, Keelung, Taiwan 202, ROC.
authors: Yong-Chin
authors: YC
authors: Lin
authors: Baskaralingam
authors: B
authors: Vaseeharan
authors: Jiann-Chu
authors: JC
authors: Chen
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D018076:DNA, Complementary; D006434:Hemocytes / Q000378:metabolism; D008969:Molecular Sequence Data; D033561:Penaeidae / Q000145:classification / Q000235:genetics* / Q000254:growth & development; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D000511:alpha-Macroglobulins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D018076:DNA, Complementary; D000511:alpha-Macroglobulins