Sugimoto T, Tsuchimochi H, McGregor C G, Mutoh H, Shimizu T, Kurachi Y
Department of Internal Medicine, Mayo Clinic, Mayo Foundation, Rochester, MN 55905.
Biochem Biophys Res Commun. 1992 Dec 15;189(2):617-24. doi: 10.1016/0006-291x(92)92245-s.
PAF decreases cardiac contractility and blood pressure. To characterize the cardiac PAF receptor, we screened a human ventricular cDNA library in a low stringency condition, using a PCR product derived from guinea pig lung PAF receptor as a probe. Four clones were obtained and named HV1-4. In Xenopus oocytes injected with cRNA derived from HV3 or 4 but not from HV1 or 2, PAF elicited a Ca(2+)-activated Cl- current. HV3 and HV4 were duplicate clones, encoding a 342 amino-acid polypeptide which was identical to that of the human leukocyte PAF receptor. However, a portion of the 5' untranslated region of HV3 (or 4) was different from that of the leukocyte receptor cDNA. Northern blotting of human ventricles and atria using the HV3 insert showed a single band of approximately 4 kb. These results suggest a tissue-specific translational mechanism responsible for regulation of the expression of the PAF receptor mRNA in these tissues.
血小板活化因子（PAF）可降低心脏收缩力和血压。为了鉴定心脏PAF受体，我们以豚鼠肺PAF受体的PCR产物为探针，在低严谨条件下筛选人心室cDNA文库。获得了四个克隆，命名为HV1 - 4。在注射了源自HV3或4而非HV1或2的cRNA的非洲爪蟾卵母细胞中，PAF引发了一种Ca(2 +)激活的Cl-电流。HV3和HV4是重复克隆，编码一种342个氨基酸的多肽，与人白细胞PAF受体的多肽相同。然而，HV3（或4）的5'非翻译区的一部分与白细胞受体cDNA的不同。使用HV3插入片段对人心室和心房进行Northern印迹分析，显示出一条约4 kb的单带。这些结果提示存在一种组织特异性翻译机制，负责调控这些组织中PAF受体mRNA的表达。
