Quarto N, Finger F P, Rifkin D B
Department of Cell Biology, New York University, New York.
J Cell Physiol. 1991 May;147(2):311-8. doi: 10.1002/jcp.1041470217.
Basic fibroblast growth factor (bFGF) is a member of the heparin-binding growth factor (HBGF) family that includes at least seven species. These proteins are potent regulators of a number of cellular processes, including cell division and angiogenesis. Multiple forms of bFGF exist differing only in the length of their NH2-terminal extensions. These species of bFGF also have unique subcellular distributions. The smallest form (18 kD) occurs predominantly in the cytosol, while the higher molecular weight forms (22, 22.5, 24 kD) are associated with the nucleus and ribosomes. Here we report that the nuclear localization of the higher molecular weight forms of bFGF derives specifically from the amino acid sequences within the NH2-terminal extension. This has been demonstrated by constructing a chimeric protein containing the NH2-terminal extension of the highest molecular weight form of bFGF fused to beta-galactosidase (beta-gal). After transfection in a transient expression system, the chimeric protein accumulated in the nuclei of transfected cells, while the wild-type beta-gal was found predominantly in the cytoplasm.
碱性成纤维细胞生长因子（bFGF）是肝素结合生长因子（HBGF）家族的成员之一，该家族至少包括七种蛋白质。这些蛋白质是许多细胞过程的有效调节因子，包括细胞分裂和血管生成。bFGF存在多种形式，仅在其NH2末端延伸的长度上有所不同。这些bFGF种类也具有独特的亚细胞分布。最小的形式（18 kD）主要存在于细胞质中，而较高分子量的形式（22、22.5、24 kD）与细胞核和核糖体相关。在此我们报告，bFGF较高分子量形式的核定位 specifically 源自NH2末端延伸内的氨基酸序列。通过构建一种嵌合蛋白已证明了这一点，该嵌合蛋白包含与β-半乳糖苷酶（β-gal）融合的bFGF最高分子量形式的NH2末端延伸。在瞬时表达系统中进行转染后，嵌合蛋白在转染细胞的细胞核中积累，而野生型β-gal主要存在于细胞质中。 （注：原文中“specifically”翻译为“具体地”不太符合语境，这里根据上下文意译为“专门地”更通顺些，你可根据实际需求调整）
