Katoh K, Takeshita S, Sato M, Ito T, Amann E
Pharma Research Laboratories, Hoechst Japan Limited, Saitama.
DNA Cell Biol. 1992 Dec;11(10):735-43. doi: 10.1089/dna.1992.11.735.
The mouse OSF-1 protein (also known as pleiotrophin, HB-GAM, HBGF-8, or HBNF) gene was isolated from a mouse genomic library and sequenced. OSF-1 is a 15-kD secreted protein specifically expressed in bone and brain, and is believed to play a role in brain development and osteogenesis. The mouse OSF-1 gene consists of at least 5 exons and 4 introns and spans > 32 kb. Computer analysis of approximately 4 kb of 5'-flanking sequence of the OSF-1 gene revealed two candidate promoter regions. One candidate promoter contains a thyroid hormone/retinoic acid-responsive element and the other contains two glucocorticoid-responsive elements. DNA sequence analysis of novel OSF-1 cDNA clones indicates that two promoters can be utilized in MC3T3-E1 osteoblastic cells. The overall organization of the mouse OSF-1 gene is similar and the locations of the three exon-intron junctions within the coding region are identical to the mouse gene encoding the differentiation-related factor midkine (MK). Based on this similarity and on the high degree of nucleotide sequence homology (approximately 55%) of mouse OSF-1 and mouse MK, we conclude that OSF-1 and MK are generated from a common ancestral gene and are members of a family of structurally and probably functionally related proteins.
从小鼠基因组文库中分离并测序了小鼠OSF-1蛋白（也称为多效生长因子、HB-GAM、HBGF-8或HBNF）基因。OSF-1是一种15kD的分泌蛋白，在骨骼和大脑中特异性表达，被认为在大脑发育和骨生成中起作用。小鼠OSF-1基因至少由5个外显子和4个内含子组成，跨度大于32kb。对OSF-1基因约4kb的5'侧翼序列进行计算机分析，发现了两个候选启动子区域。一个候选启动子含有甲状腺激素/视黄酸反应元件，另一个含有两个糖皮质激素反应元件。对新的OSF-1 cDNA克隆进行DNA序列分析表明，两个启动子可在MC3T3-E1成骨细胞中被利用。小鼠OSF-1基因的总体结构相似，编码区三个外显子-内含子连接点的位置与编码分化相关因子中期因子（MK）的小鼠基因相同。基于这种相似性以及小鼠OSF-1和小鼠MK的高度核苷酸序列同源性（约55%），我们得出结论，OSF-1和MK源自一个共同的祖先基因，是结构上可能功能相关的蛋白质家族的成员。
