Mesa K, Gebelein B, Cook T, Urrutia R
Gastroenterology Research Unit, Saint Mary's Hospital, Rochester, MN 55905, USA.
Cancer Lett. 1996 Jun 5;103(2):143-9. doi: 10.1016/0304-3835(96)04204-8.
Zinc finger transcription factors are DNA-binding proteins that are known to determine the identity of cells by regulating cell-specific gene expression. In addition, mutations in some members of this family have been found to be associated with several neoplasias, including Wilms' tumor and leukemias. Because the mechanisms that regulate normal, as well as neoplastic, pancreatic cell differentiation are poorly understood, we are searching for pancreas-enriched transcription factors that may determine the identity of pancreatic cells. Towards this end, we have used the polymerase chain reaction and degenerate primers against the highly conserved (Cys2-His2) zinc finger domain to amplify novel transcription factor encoding cDNAs from the well-characterized pancreatic acinar cell line AR42J. Using this approach, we have identified 17 different zinc finger encoding cDNAs (AZF-1 to -17). Sequence analysis shows that all of these clones encode for different zinc finger peptides which share the consensus DNA binding motif with the Drosophila transcription factor krüppel. As a first step in the characterization of these genes, the purified PCR products were used to determine their spatial pattern of expression by northern blot analysis. Using these techniques, we find that numerous zinc finger encoding genes are expressed in AR42J acinar cells as well as in normal adult rat pancreas and suggest that they may play a role as transcription factors in exocrine pancreatic cells.
锌指转录因子是一类DNA结合蛋白，已知其通过调节细胞特异性基因表达来决定细胞的特性。此外，已发现该家族某些成员的突变与几种肿瘤形成有关，包括肾母细胞瘤和白血病。由于调节正常以及肿瘤性胰腺细胞分化的机制尚不清楚，我们正在寻找可能决定胰腺细胞特性的胰腺富集转录因子。为此，我们使用聚合酶链反应和针对高度保守的（Cys2-His2）锌指结构域的简并引物，从特征明确的胰腺腺泡细胞系AR42J中扩增编码新型转录因子的cDNA。使用这种方法，我们鉴定出了17种不同的编码锌指的cDNA（AZF-1至-17）。序列分析表明，所有这些克隆都编码不同的锌指肽，它们与果蝇转录因子克虏伯具有共同的DNA结合基序。作为对这些基因进行表征的第一步，纯化的PCR产物通过Northern印迹分析用于确定它们的空间表达模式。使用这些技术，我们发现许多编码锌指的基因在AR42J腺泡细胞以及正常成年大鼠胰腺中表达，并表明它们可能在外分泌胰腺细胞中作为转录因子发挥作用。
