Emami S, Regnauld K, Ferrand N, Astesano A, Pessah M, Phan H, Boissard C, Garel J M, Rosselin G
Institut National de la Santé et de la Recherche Médicale, Centre de Recherche Paris Saint-Antoine, France.
Ann N Y Acad Sci. 1998 Dec 11;865:118-31. doi: 10.1111/j.1749-6632.1998.tb11170.x.
We have determined the cellular distribution of different alpha subtypes of G proteins and adenylyl cyclase (AC) isoforms in endocrine, exocrine, and established pancreatic cell lines. VIP, PACAP, and tGLP-1 receptor proteins are expressed to varying extents in A and B cells, whereas the expression of G alpha subunits is cell specific. Thus, G(olf) alpha is detected in normal rodent B cells and immortalized pancreatic B cell lines, whereas Gs alpha is more ubiquitously expressed. The cellular density of AC isoforms labeling (I, II, III, IV, V/VI) is also islet cell-specific and their distribution is age- and species-dependent. The identification of numerous signaling molecule subtypes, together with the discovery of their specific subcellular distribution, will help the functional characterization of their intraregulatory pathways, leading to the extrusion of insulin or glucagon secretory granules, and those leading to differentiation and apoptosis of islet cells.
我们已经确定了G蛋白不同α亚型和腺苷酸环化酶（AC）同工型在内分泌、外分泌和已建立的胰腺细胞系中的细胞分布。血管活性肠肽（VIP）、垂体腺苷酸环化酶激活肽（PACAP）和胰高血糖素样肽-1（tGLP-1）受体蛋白在A细胞和B细胞中表达程度各异，而Gα亚基的表达具有细胞特异性。因此，在正常啮齿动物B细胞和永生化胰腺B细胞系中可检测到G(olf)α，而Gsα的表达更为普遍。AC同工型标记（I、II、III、IV、V/VI）的细胞密度也具有胰岛细胞特异性，其分布取决于年龄和物种。众多信号分子亚型的鉴定，以及它们特定亚细胞分布的发现，将有助于对其细胞内调节途径进行功能表征，这些途径导致胰岛素或胰高血糖素分泌颗粒的排出，以及导致胰岛细胞的分化和凋亡。
