关键词: 连接黏附分子A, 基因克隆, 呼肠孤病毒, 树鼩

Abstract: Objective    To explore the mechanism of junctional adhesion molecule A (JAM-A) as a reovirus receptor to invade the primary lung cells of tree shrew. Methods    Total RNA was extracted from normal tree shrew tissues. JAM-A gene sequences were obtained by reverse transcription-PCR and rapid-amplification of cDNA ends. Translation of amino acids encoded by JAM-A gene were analyzed by using Unipro UGENE software. The phylogenetic tree was constructed by MEGA 6.0 software using the maximum likelihood method. Using real-time fluorescent quantitative-PCR to detect the relative expression level of JAM-A in 25 tissues and blood of tree shrew. The specific antibody blocking treatment of the receptor was performed on the primary tree shrew alveolar epithelial cells, and the fluorescence intensity of the virus antigen after reovirus infection was determined. Results    The full-length cDNA sequences of JAM-A gene with 2 962 bp were obtained. Amino acid alignment and phylogenetic tree analysis showed that the genetic relationship of JAM-A gene in tree shrew was more closer to human than that of rodent. JAM-A molecule was widely expressed in the peripheral tissues of tree shrews, with the more higher expression levels in the respiratory and digestive tract. The integrated absorbance of the immunofluorescence of the virus antigen after the specific antibody was applied to the cells was significantly decreased (P<0.000 1). Conclusion   The whole sequence of JAM-A gene was retrieved and analyzed for the first time, and the JAM-A molecule was verified to be the main receptor for reovirus to invade tree shrew, suggesting that tree shrew may be used as a new animal model of reovirus.

Key words: Junctional adhesion molecule A, Gene cloning, Reovirus, Tree shrew