Cloning and characterization of an abundant subtype of the human calcitonin receptor.
Cloning and characterization of an abundant subtype of the human calcitonin receptor.
复制标题
人类降钙素受体丰富亚型的克隆和表征。
DOI：
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发表时间：
1994
影响因子：
3.6
通讯作者：
Deborah L. Thompson
中科院分区：
文献类型：
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作者：
R. Kuestner;R. Elrod;F. Grant;F. Hagen;J. Kuijper;S. L. Matthewes;P. O'hara;P. Sheppard;S. Stroop;Deborah L. Thompson
我们已经从T47 D细胞中克隆并鉴定了人降钙素受体的第二种形式。它类似于Gorn等人[J. Clin. Invest. 90：1726-1735（1992）]，不同之处在于其在推定的第一胞内环中缺乏16个氨基酸的插入物。插入物阴性受体似乎是最丰富的形式，并且其在所有表达组织中以相对恒定的水平出现。相比之下，插入物阳性受体在大多数组织中以低水平存在，但其表达水平似乎变化更大。插入阴性cDNA在幼仓鼠肾细胞中稳定表达。与内源性T47 D受体一样，重组受体对鲑鱼和猪降钙素具有同样高的亲和力，但对人降钙素的亲和力低3-4倍。高浓度的降钙素基因相关肽、大鼠胰淀素、胰泌素或血管活性肠肽不会与降钙素显著竞争结合重组受体。降钙素刺激T47 D和转染的幼仓鼠肾细胞中的cAMP应答。鲑鱼降钙素比人降钙素对T47 D细胞更有效，但两者对转染子的效力几乎相等。此外，转染子中cAMP应答的ED 50比T47 D细胞低10-100倍。降钙素刺激磷酸肌醇周转和提高内部钙水平的转染。这种反应需要非生理水平的降钙素，并与受体的数量直接相关。最后，通过使用人/啮齿动物体细胞杂交面板和原位杂交，我们将人降钙素受体基因定位于7号染色体。
We have cloned and characterized a second form of the human calcitonin receptor from T47D cells. It resembles the clone described by Gorn et al. [J. Clin. Invest. 90:1726-1735 (1992)] except that it lacks a 16-amino acid insert in the putative first intracellular loop. The insert-negative receptor appears to be the most abundant form, and it occurs at a relatively constant level in all expressing tissues. In contrast, the insert-positive receptor is found at low levels in most tissues but its expression levels appear to be much more variable. The insert-negative cDNA was stably expressed in baby hamster kidney cells. Like the endogenous T47D receptor, the recombinant receptor has an equally high affinity for salmon and porcine calcitonin but a 3-4-fold lower affinity for human calcitonin. High concentrations of calcitonin gene-related peptide, rat amylin, secretin, or vasoactive intestinal peptide do not significantly compete with calcitonin for binding to the recombinant receptor. Calcitonin stimulates a cAMP response in both T47D and transfected baby hamster kidney cells. Salmon calcitonin is more potent than human calcitonin for T47D cells, but the two are nearly equipotent for the transfectants. Furthermore, the ED50 for the cAMP response in the transfectants is 10-100-fold lower than in T47D cells. Calcitonin stimulates inositol phosphate turnover and elevates internal calcium levels in the transfectants. This response requires non-physiological levels of calcitonin and is directly correlated with the number of receptors. Lastly, by using a human/rodent somatic cell hybrid panel and in situ hybridization, we localized the human calcitonin receptor gene to chromosome 7.