Huang K, Sommers C L, Grinberg A, Kozak C A, Love P E
Laboratory of Mammalian Genes and Development, NICHD, NIH, Bethesda, Maryland 20892, USA.
Oncogene. 1996 Oct 3;13(7):1567-73.
A novel nonreceptor protein tyrosine phosphatase (PTP), PTP-K1, was identified using a consensus polymerase chain reaction-based approach. The full length cDNA encompasses an open reading frame of 1362 base pairs, predicting a protein of 453 amino acid residues with a molecular mass of 54 kDa. The PTP domain is located in the N-terminal portion of the molecule and shares approximately 50% amino acid identify with two other nonreceptor PTPs: PEP and PTP-PEST. PTP-K1 is preferentially expressed in mouse bone marrow with transcripts of 1.7 kb, 1.9 kb and 3.5 kb. The 1.7 kb transcript was also detected in kidney, lung and ovary. The PTP domain of PTP-K1 was expressed as a fusion protein in bacteria and had intrinsic PTP catalytic activity. Indirect immunofluorescence microscopy in COS-7 cells showed that PTP-K1 was localized to the cytoplasm. Ptp-k1 was mapped to mouse chromosome 1, and was closely linked to the interleukin-1 receptor gene. The high level expression of PTP-K1 mRNA in bone marrow suggests that PTP-K1 may be involved in signal transduction in growth and differentiation of hematopoietic cells.
采用基于聚合酶链反应共有序列的方法鉴定出一种新型非受体蛋白酪氨酸磷酸酶（PTP），即PTP-K1。全长cDNA包含一个1362个碱基对的开放阅读框，预测其编码的蛋白质由453个氨基酸残基组成，分子量为54 kDa。PTP结构域位于分子的N端部分，与另外两种非受体PTP（PEP和PTP-PEST）的氨基酸序列一致性约为50%。PTP-K1在小鼠骨髓中优先表达，有1.7 kb、1.9 kb和3.5 kb的转录本。在肾脏、肺和卵巢中也检测到了1.7 kb的转录本。PTP-K1的PTP结构域在细菌中表达为融合蛋白，并具有内在的PTP催化活性。在COS-7细胞中进行的间接免疫荧光显微镜观察显示，PTP-K1定位于细胞质。Ptp-k1被定位到小鼠1号染色体上，并且与白细胞介素-1受体基因紧密连锁。PTP-K1 mRNA在骨髓中的高水平表达表明，PTP-K1可能参与造血细胞生长和分化中的信号转导。
