Bartoli C, Baeza N, Figarella C, Pellegrini I, Figarella-Branger D
Laboratoire de Biopathologie Nerveuse et Musculaire, Institut de Biologie du D'eveloppement de Marseille, Université de la Méditerranée, France.
J Clin Endocrinol Metab. 1998 Nov;83(11):4041-6. doi: 10.1210/jcem.83.11.5217.
Peptide 23, the rat homolog of the human pancreatitis-associated protein (PAP)/hepatocarcinoma-intestine-pancreas (HIP) protein, has been identified in primary culture of rat pituitary cells. Its secretion was shown to be stimulated by GH-releasing factor and inhibited by somatostatin in a similar fashion to GH. This observation led the researchers to speculate that peptide 23 does have a physiological hormonal role. We tested this hypothesis by screening by RT-PCR reactions the expression of the PAP/HIP gene in several human pituitary adenomas, especially GH-producing adenomas. Our results show a weak expression of the PAP/HIP gene in the pituitary gland and in most of the tumors, but independent of their origin. The significant homology of the PAP/HIP gene to the Reg gene family prompted us to study in the same pituitary adenomas the presence of the related Reg genes. Reg expression was never observed in the adenomas tested or in the pituitary gland. In contrast, the RegL transcript was observed in pituitary gland and in some subtypes of adenomas. We then extended our work to normal adults and developing human tissues to compare the expression patterns of the PAP/Reg gene family. We observed the presence of the PAP/HIP transcript in each tissue tested. In contrast, the Reg gene was expressed only in fetal pancreas and in some adult tissues, whereas the RegL gene was expressed not only in fetal pancreas but also in fetal colon and brain as well as some adult tissues. In conclusion, our results show that all of the human fetal and adult tissues examined express at least one of the different transcripts of the PAP/Reg family, suggesting that the regulation of these homologous genes is coordinately controlled.
肽23是人类胰腺炎相关蛋白（PAP）/肝癌-肠-胰腺（HIP）蛋白的大鼠同源物，已在大鼠垂体细胞原代培养物中被鉴定出来。研究表明，其分泌受生长激素释放因子刺激，并受生长抑素抑制，方式与生长激素类似。这一观察结果促使研究人员推测肽23确实具有生理激素作用。我们通过逆转录聚合酶链反应（RT-PCR）筛选了几种人类垂体腺瘤，特别是生长激素分泌型腺瘤中PAP/HIP基因的表达，以验证这一假设。我们的结果显示，PAP/HIP基因在垂体和大多数肿瘤中表达较弱，但与肿瘤起源无关。PAP/HIP基因与Reg基因家族具有显著同源性，这促使我们在同一垂体腺瘤中研究相关Reg基因的存在情况。在所检测的腺瘤或垂体中均未观察到Reg表达。相反，在垂体和某些腺瘤亚型中观察到了RegL转录本。然后，我们将研究扩展到正常成年人和发育中的人体组织，以比较PAP/Reg基因家族的表达模式。我们在所检测的每个组织中都观察到了PAP/HIP转录本的存在。相比之下，Reg基因仅在胎儿胰腺和一些成人组织中表达，而RegL基因不仅在胎儿胰腺中表达，还在胎儿结肠、大脑以及一些成人组织中表达。总之，我们的结果表明，所检测的所有人类胎儿和成人组织都至少表达了PAP/Reg家族不同转录本中的一种，这表明这些同源基因的调控是协同控制的。
