Zhang J, Yu L, Fu Q, Gao J, Xie Y, Chen J, Zhang P, Liu Q, Zhao S
State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Science, Fudan University, No. 220 Handan Road, Shanghai 200433, P.R. China.
Gene. 2001 Feb 21;264(2):273-9. doi: 10.1016/s0378-1119(00)00597-7.
Two mouse cDNAs encoding the non-muscle-specific or brain isoform (type B, Pgam1) and the muscle-specific isoform (type M, Pgam2) of phosphoglycerate mutase (PGAM) were isolated and characterized. Pgam1 contains a 765 bp open reading frame (ORF) coding for a 254-residue protein while Pgam2 contains a 762 bp ORF coding for a 253-residue protein. The deduced proteins of mouse Pgam1 and Pgam2 are highly similar to those of human and rat (> or = 93% similarity). Northern blot analysis showed that the expression patterns of Pgam1 and Pgam2 were distinct. Pgam1 was expressed as a 2.1-kb transcript highly in brain and kidney and moderately in liver, thyroid, stomach and heart, whereas Pgam2 was expressed as a 1.0-kb transcript highly in muscle, testis and moderately in heart and lung, but was not detectable in the other six tissues examined. Transfecting the cDNA fragments containing the entire ORFs of these two cDNAs into COS7 cells for transient expression, respectively, the enzyme activities of mouse Pgam1 and Pgam2 were detected to be 2.2-2.5 times of those of COS7 cells and COS7 cells transfected with vector, proving the validity of mouse Pgam1 and Pgam2 cDNAs we report here. Pgam1 and Pgam2 were assigned to 116.16 cR from D19Mit52 and 29.57 cR from D11Mit129, respectively, by radiation hybrid method. The partial genomic sequence of Pgam2 was determined, which showed that mouse Pgam2 consisted at least three exons and two introns. In addition, a pseudogene of Pgam1, Pgam1-ps1, was identified from mouse genomic sequence.
分离并鉴定了两个编码磷酸甘油酸变位酶（PGAM）非肌肉特异性或脑同工型（B型，Pgam1）和肌肉特异性同工型（M型，Pgam2）的小鼠cDNA。Pgam1包含一个765 bp的开放阅读框（ORF），编码一个254个氨基酸的蛋白质，而Pgam2包含一个762 bp的ORF，编码一个253个氨基酸的蛋白质。小鼠Pgam1和Pgam2推导的蛋白质与人及大鼠的蛋白质高度相似（相似性≥93%）。Northern印迹分析表明，Pgam1和Pgam2的表达模式不同。Pgam1以2.1 kb的转录本形式在脑和肾中高表达，在肝、甲状腺、胃和心脏中中度表达，而Pgam2以1.0 kb的转录本形式在肌肉、睾丸中高表达，在心脏和肺中中度表达，但在所检测的其他六种组织中未检测到。分别将包含这两个cDNA完整ORF的cDNA片段转染到COS7细胞中进行瞬时表达，检测到小鼠Pgam1和Pgam2的酶活性分别是COS7细胞和转染载体的COS7细胞的2.2 - 2.5倍，证明了我们在此报道的小鼠Pgam1和Pgam2 cDNA的有效性。通过辐射杂交法，Pgam1和Pgam2分别被定位到距D19Mit52 116.16 cR和距D11Mit129 29.57 cR处。测定了Pgam2的部分基因组序列，结果表明小鼠Pgam2至少由三个外显子和两个内含子组成。此外，从小鼠基因组序列中鉴定出了Pgam1的一个假基因Pgam1-ps1。
