Analysis of the primary sequence and microtubule-binding region of the Drosophila 205K MAP.
Analysis of the primary sequence and microtubule-binding region of the Drosophila 205K MAP.
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DOI：
10.1083/jcb.111.6.2563
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发表时间：
1990-12
期刊：
影响因子：
--
通讯作者：
Goldstein LS
中科院分区：
文献类型：
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作者：
Irminger-Finger I;Laymon RA;Goldstein LS
我们对果蝇205K微管相关蛋白（MAP）的cDNA克隆进行了测序，该蛋白可能是哺乳动物MAP4的物种特异性同源物。从最长的开放阅读框中推断出的肽序列揭示了一个亲水蛋白，它具有与哺乳动物MAP2相似的碱性和酸性区域。使用截断形式的205K MAP，可以定义一个232个氨基酸的区域，这是微管结合所必需的。该区域的氨基酸序列与MAP2或tau的结合基序无相似性。我们还分析了几个胚胎cDNA克隆，这些克隆显示存在差异剪接的mrna。最后，我们确定了几个潜在的蛋白激酶靶序列。其中一个位于微管结合位点的远端，符合有丝分裂特异性蛋白激酶cdc2磷酸化蛋白的磷酸化一致序列。我们的数据表明，与其他MAP不同，205K MAP使用了一个微管结合基序，这也提出了205K MAP的活性可能受到选择性剪接和磷酸化的调节。
We have sequenced cDNA clones encoding the Drosophila 205K microtubule- associated protein (MAP), a protein that may be the species specific homologue of mammalian MAP4. The peptide sequence deduced from the longest open-reading frame reveals a hydrophilic protein, which has basic and acidic regions that are similar in organization to mammalian MAP2. Using truncated forms of the 205K MAP, a 232-amino acid region could be defined that is necessary for microtubule binding. The amino acid sequence of this region shares no similarity with the binding motif of MAP2 or tau. We also analyzed several embryonic cDNA clones, which show the existence of differentially spliced mRNAs. Finally, we identified several potential protein kinase target sequences. One of these is distal to the microtubule-binding site and fits the phosphorylation consensus sequence of proteins phosphorylated by the mitosis specific protein kinase cdc2. Our data suggest that the 205K MAP uses a microtubule-binding motif unlike that found in other MAPs, and also raise the possibility that the activities of the 205K MAP may be regulated by alternative splicing and phosphorylation.