Vaughan T J, James P S, Pascall J C, Brown K D
Department of Cellular Physiology, A.F.R.C. Institute of Animal Physiology and Genetics Research, Babraham, Cambridge, U.K.
Biochem J. 1993 Dec 15;296 ( Pt 3)(Pt 3):837-42. doi: 10.1042/bj2960837.
Transforming growth factor alpha (TGF alpha) was originally identified as a product of tumour tissues and transformed cells in culture. Although it is now clear that expression of this factor is not restricted to neoplastic cells, there remains relatively little information about the sites of expression of TGF alpha in normal tissues. Therefore, an amplified DNA fragment encoding the pig TGF alpha precursor was cloned by reverse transcription-PCR (RT-PCR) using RNA isolated from normal skin tissue as the template. Nucleotide sequence analysis predicts a 160-residue transmembrane polypeptide that differs from the rat, mouse and human TGF alpha precursors at 14, 15 and six sites respectively. The distribution of TGF alpha mRNA in a wide variety of pig tissues was analysed by RT-PCR, using oligonucleotide primers based on the pig TGF alpha cDNA sequence. TGF alpha transcripts were detected in RNA isolated from 17 of the 22 tissues analysed, including four previously unreported sites. Using an antibody raised against a synthetic TGF alpha peptide, we have immunolocalized TGF alpha protein to cells within the red pulp of the spleen and to the distal convoluted tubules of the kidney.
转化生长因子α（TGFα）最初被鉴定为肿瘤组织和培养中的转化细胞的产物。尽管现在清楚该因子的表达并不局限于肿瘤细胞，但关于TGFα在正常组织中的表达位点的信息仍然相对较少。因此，以从正常皮肤组织分离的RNA为模板，通过逆转录PCR（RT-PCR）克隆了编码猪TGFα前体的扩增DNA片段。核苷酸序列分析预测了一种160个残基的跨膜多肽，它在14、15和6个位点分别与大鼠、小鼠和人类TGFα前体不同。使用基于猪TGFα cDNA序列的寡核苷酸引物，通过RT-PCR分析了TGFα mRNA在多种猪组织中的分布。在所分析的22种组织中的17种组织分离的RNA中检测到了TGFα转录本，包括4个先前未报道的位点。使用针对合成TGFα肽产生的抗体，我们已将TGFα蛋白免疫定位到脾脏红髓内的细胞和肾脏的远曲小管。
