Balcarek J M, Cowan N J
Nucleic Acids Res. 1985 Aug 12;13(15):5527-43. doi: 10.1093/nar/13.15.5527.
We report the complete sequence of the gene encoding mouse glial fibrillary acidic protein (GFAP), the intermediate filament (IF) protein specific to astrocytes. The 9.8 kb gene includes nine exons separated by introns ranging in size from 0.2 to 2.5 kb. A comparison of the organization of the GFAP gene with that of genes encoding other IF proteins reveals that the structure of IF genes is highly conserved in spite of considerable divergence at the amino acid level. Thus, most of the evolutionary events leading to the placement of introns in IF genes must have occurred prior to the duplication and subsequent divergence of IF genes from a presumptive common ancestral sequence. The conserved gene organization is unrelated to structural features of IF proteins. A curious feature of the GFAP gene is the large number of repeated sequences found in the introns. Six tracts of reiterated di- or trinucleotides are present, plus tandem repeats of two different novel sequences. One repeat is unique to the GFAP gene; the other occurs elsewhere in the mouse genome, although at relatively low frequency.
我们报道了编码小鼠胶质纤维酸性蛋白（GFAP）的基因的完整序列，GFAP是星形胶质细胞特有的中间丝（IF）蛋白。这个9.8kb的基因包含9个外显子，被大小从0.2到2.5kb不等的内含子隔开。将GFAP基因的结构组织与编码其他IF蛋白的基因相比较发现，尽管在氨基酸水平上存在相当大的差异，但IF基因的结构高度保守。因此，导致内含子在IF基因中定位的大多数进化事件肯定发生在IF基因从假定的共同祖先序列复制并随后分化之前。保守的基因结构组织与IF蛋白的结构特征无关。GFAP基因的一个奇特特征是在内含子中发现大量重复序列。存在6个双核苷酸或三核苷酸重复序列片段，以及两种不同新序列的串联重复。一种重复序列是GFAP基因特有的；另一种在小鼠基因组的其他地方也有出现，不过频率相对较低。
