Dicou E, Lee J, Brachet P
Proc Natl Acad Sci U S A. 1986 Sep;83(18):7084-8. doi: 10.1073/pnas.83.18.7084.
Nerve growth factor (NGF) mRNAs were detected in the thyroid and parathyroid glands by hybridization to a preproNGF and a NGF-beta cDNA probe. The thyroid NGF transcript was identical in size to that found in the mouse submaxillary gland. Mature NGF-beta was not detected in the thyroid tissue either by immunoprecipitation or by immunohistochemical methods. In contrast, an antiserum directed against the predicted precursor protein sequence immunoprecipitated a protein of Mr 30,000-31,000 in thyroid extracts. A protein of identical molecular weight was also detected by this serum in the mouse submaxillary gland extracts. In vitro translation of hybrid-selected NGF RNAs detected two peptides of Mrs 35,000 and 28,000. These peptides closely correspond to the proposed translation products of the preproNGF mRNA sequence, suggesting that two different initiation codons can be utilized, at least in vitro. The proNGF antiserum also cross-reacted with the in vitro synthesized Mr 35,000 peptide. The antigenic determinant recognized by the precursor-specific antibody was localized to the convoluted granular tubules of the mouse submaxillary gland, known to be the site of synthesis of the NGF-beta. We present evidence for the localization of unprocessed proNGF in the parathyroid gland and in some parafollicular cells of the thyroid.
通过与前体神经生长因子（preproNGF）和神经生长因子β（NGF-β）cDNA探针杂交，在甲状腺和甲状旁腺中检测到了神经生长因子（NGF）mRNA。甲状腺中的NGF转录本大小与在小鼠颌下腺中发现的相同。无论是通过免疫沉淀法还是免疫组织化学方法，在甲状腺组织中均未检测到成熟的NGF-β。相反，一种针对预测的前体蛋白序列的抗血清在甲状腺提取物中免疫沉淀出一种分子量为30,000 - 31,000的蛋白。在小鼠颌下腺提取物中，该血清也检测到了相同分子量的蛋白。对杂交筛选的NGF RNA进行体外翻译，检测到了分子量分别为35,000和28,000的两种肽段。这些肽段与preproNGF mRNA序列预测的翻译产物密切对应，表明至少在体外可以利用两个不同的起始密码子。前体神经生长因子（proNGF）抗血清也与体外合成的分子量为35,000的肽段发生交叉反应。前体特异性抗体识别的抗原决定簇定位于小鼠颌下腺的曲管颗粒小管，已知该部位是NGF-β的合成位点。我们提供了未加工的proNGF在甲状旁腺和甲状腺一些滤泡旁细胞中定位的证据。
