IDENTIFICATION OF 2 ALTERNATIVELY SPLICED TRANSCRIPTS OF STEP - A SUBFAMILY OF BRAIN-ENRICHED PROTEIN-TYROSINE PHOSPHATASES
IDENTIFICATION OF 2 ALTERNATIVELY SPLICED TRANSCRIPTS OF STEP - A SUBFAMILY OF BRAIN-ENRICHED PROTEIN-TYROSINE PHOSPHATASES
复制标题
DOI：
10.1016/0169-328x(95)00066-2
复制
发表时间：
1995-08-01
期刊：
影响因子：
--
通讯作者：
LOMBROSO, PJ
中科院分区：
文献类型：
--
作者：
SHARMA, E;ZHAO, FS;LOMBROSO, PJ
先前分离并鉴定了一种脑富集型蛋白酪氨酸磷酸酶，称为STEP(46)(纹状体富集型磷酸酶)。用STEP单抗进行的免疫学研究识别了几种STEP免疫反应蛋白，并提示存在额外的STEP相关多肽。本研究分离了STEP基因的两个选择性剪接转录本。其中一个步骤(20)(预测分子质量为20M)被进一步鉴定，并发现缺乏保守的酪氨酸磷酸酶结构域。Northern分析在小鼠大脑中检测到一条2.8kb的Step(20)信息。第二个选择性剪接的转录本，STEP(61)，有一个5‘延伸的开放阅读框，编码一个预测分子质量为61 kDa的蛋白质，并包含一个单一的酪氨酸磷酸酶结构域。在小鼠STEP基因组DNA中确定了负责新的STEP(20)和STEP(61)序列的外显子-内含子组织。我们认为，最初的STEP(46)、STEP(20)和STEP(61)是大脑丰富的蛋白酪氨酸磷酸酶61亚家族的成员，并且STEP亚型可能在中枢神经系统中具有不同的功能。
A brain-enriched protein tyrosine phosphatase termed STEP(46) (striatal enriched phosphatase) was previously isolated and characterized. Immunological studies with a STEP monoclonal antibody recognized several STEP-immunoreactive proteins, and suggested that additional STEP-related polypeptides existed. This study reports the isolation of two alternatively spliced transcripts of the STEP gene. One of these, STEP(20) (with a predicted molecular mass of 20 M)a) was further characterized and found to lack the conserved tyrosine phosphatase domain. Northern analysis detected a 2.8 kb STEP(20) message in mouse brain. The second alternatively spliced transcript, STEP(61), has a 5'-extended open reading frame that encodes a protein with a predicted molecular mass of 61 kDa and contains a single tyrosine phosphatase domain. The exon-intron organization responsible for the novel STEP(20) and STEP(61) sequences was determined in the mouse STEP genomic DNA. We propose that the original STEP(46), along with STEP(20) and STEP(61), are members of a brain-enriched 61, subfamily of protein tyrosine phosphatases, and that STEP isoforms may have distinct functions within the central nervous system.