Shattuck-Brandt R L, Wood L D, Richmond A
Department of Cell Biology, Vanderbilt University School of Medicine, Nashville, TN, 37212-2637, USA.
DNA Seq. 1997;7(6):379-86. doi: 10.3109/10425179709034060.
Three linked genes for the CXC-chemokine melanoma growth stimulatory activity/growth related protein (MGSA/GRO) have been previously characterized and mapped to chromosome 4q12-q13. We have isolated and characterized a pseudogene, MGSA/GRO delta, which is 83% similar to the MGSA/GRO alpha gene in the region spanning the 5' UTR, first and second exons, and the first intron. The 5' upstream sequence for the MGSA/GRO delta gene, which is also very similar to the MGSA/GRO alpha, beta, gamma genes, contains a conserved NF-kappa B motif, a TATA box, and a transcription initiation site. However, the sequence becomes markedly divergent after the second exon and hybridization studies indicate that sequences similar to the third and forth exons of other MGSA/GRO genes are not present in this gene. Additional sequence differences include alteration of the MGSA/GRO delta translation initiation codon and a one base insertion resulting in an apparent frame shift and early termination within exon 2. Multiple mutations such as these are characteristic of pseudogenes.
先前已对CXC趋化因子黑素瘤生长刺激活性/生长相关蛋白（MGSA/GRO）的三个连锁基因进行了表征，并将其定位到4号染色体q12-q13区域。我们分离并鉴定了一个假基因MGSA/GROδ，在跨越5'非翻译区、第一和第二外显子以及第一内含子的区域中，它与MGSA/GROα基因有83%的相似性。MGSA/GROδ基因的5'上游序列，也与MGSA/GROα、β、γ基因非常相似，包含一个保守的NF-κB基序、一个TATA盒和一个转录起始位点。然而，在第二外显子之后序列明显不同，杂交研究表明该基因中不存在与其他MGSA/GRO基因的第三和第四外显子相似的序列。其他序列差异包括MGSA/GROδ翻译起始密码子的改变以及一个碱基的插入，导致外显子2内出现明显的移码和提前终止。这样的多个突变是假基因的特征。
