WEE1-like CDK tyrosine kinase mRNA level is regulated temporally and spatially in sea urchin embryos.
WEE1-like CDK tyrosine kinase mRNA level is regulated temporally and spatially in sea urchin embryos.
复制标题
海胆胚胎中 WEE1 样 CDK 酪氨酸激酶 mRNA 水平在时间和空间上受到调节。
DOI：
10.1016/s0925-4773(96)00560-6
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发表时间：
1996
影响因子：
2.6
通讯作者：
Stuebing,EW
中科院分区：
文献类型：
--
作者：
Nemer,M;Stuebing,EW
来自海胆Strongylocentrotus purpuratus的cDNA编码624个氨基酸的多肽（WEE1S.purp），其与Mik 1和Wee 1蛋白酪氨酸激酶具有高度的相似性。这些激酶通过使细胞周期蛋白依赖性激酶（CDK）失活而作为有丝分裂的负调节剂。Wee 1活性在细胞周期中变化，并且仅在需要时产生。WEE1S.purpmRNA的表达模式进行了检查的时间和空间的海胆胚胎。只有微量的WEE1S.purpmRNA存在于卵子中，并通过受精后的第五个细胞周期。在接下来的三个囊胚中期周期中，其浓度短暂上升至每个胚胎2.5 × 104个转录本。它的发展概况在这一早期阶段是相反的报道细胞周期蛋白mRNA，这是在一个高水平的鸡蛋，并通过第五个细胞周期，然后下降后进一步发展。WEE1S.purpmRNA在原肠胚和pluteus阶段成为限制从事DNA复制的细胞，包括内胚层（肠道），口腔外胚层，和手臂的雏形。它不存在于缺乏循环细胞的反口外胚层中。WEE 1 mRNA在红腹白蛉幼虫的臂雏形中的细胞增殖和臂伸长过程中被检测到，但在臂完成后没有被检测到。在海胆Wee 1-like cDNA中推测的调控基序表明其mRNA和蛋白质具有快速更新的能力：WEE1S.purpmRNA 3′ UTR含有13个AUUUA五聚体，其特征是mRNA不稳定性的决定因素;并且预测的WEE1S.purp多肽的N-末端结构域富含含STP的潜在激酶靶位点，以及高价值的“PEST”序列，与蛋白质不稳定性有关。WEE1S.purpmRNA的发育外观可能与细胞周期中的间隙期的引入相一致。它的空间格局在胚胎发生过程中似乎反映了不同的程序，调节细胞周期在分化组织。
A cDNA from the sea urchin Strongylocentrotus purpuratus encodes a 624 amino acid polypeptide (WEE1S.purp) with a high degree of similarity to the Mik1 and Wee1 protein tyrosine kinases. These kinases act as negative regulators of mitosis by inactivating cyclin-dependent kinases (CDK).Wee1 activity varies during the cell-cycle, and is generated only when required. The pattern of WEE1S.purpmRNA expression was examined temporally and spatially in sea urchin embryos. Only a trace amount of WEE1S.purpmRNA is present in the egg and through the fifth cell cycle post-fertilization. During the next three cycles to the mid-blastula stage, its concentration rises transiently to 2.5 × 104transcripts per embryo. Its developmental profile during this early period is the inverse of that reported for cyclin mRNAs, which are at a high level in the egg and through the fifth cell cycle, then decline upon further development.WEE1S.purpmRNA in the gastrula and pluteus stages becomes restricted to cells engaged in DNA replication, including the endoderm (gut), oral ectoderm, and arm rudiments. It is absent from the aboral ectoderm, which lacks cycling cells. In the pluteus larva of the species Lytechinus pictus, WEE1 mRNA was detected in the arm rudiments during cellular proliferation and arm elongation, but not after the completion of the arms. Putative regulatory motifs in the sea urchin Wee1-like cDNA suggest a capacity for rapid turnover of both its mRNA and protein: the WEE1S.purpmRNA 3′ UTR contains 13 AUUUA pentamers, which have been characterized as determinants of mRNA lability; and the N-terminal domain of the predicted WEE1S.purppolypeptide is enriched in STP-containing, potential kinasetarget sites, as well as high-value ‘PEST’ sequences, associated with protein lability. The developmental appearance of WEE1S.purpmRNA may coincide with the introduction of a gap phase in the cell cycle. Its spatial pattern during embryogenesis appears to reflect distinct programs of regulated cell cycling in differentiating tissues.