Cloning and expression of a Chk1 gene in Daphnia pulex during different modes of reproduction
Cloning and expression of a Chk1 gene in Daphnia pulex during different modes of reproduction
复制标题
不同繁殖模式下溞 Chk1 基因的克隆和表达
DOI：
10.1007/s13258-015-0310-5
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发表时间：
2015-09-01
期刊：
影响因子：
2.1
通讯作者：
Zhao, Yunlong
中科院分区：
文献类型：
--
作者：
Guo, Xiaoge;Xu, Shanliang;Zhao, Yunlong
摘要
利用RACE技术从蚤状蚤（Daphnia pulex）中克隆了Chk1基因（DpChk1）的全长cDNA。该cDNA全长1767 bp，开放阅读框为1497 bp，编码498个氨基酸。DpChk 1蛋白序列与豌豆曲霉、豌豆根瘤菌rotundata，圆叶杜父鱼D. melanogaster、黑腹拟步行虫A. echinatior，B. terrestris、河pulchellus和M.分别为octagentalis。基因表达分析表明Chk1在D.不同繁殖方式下的蚤状幼体DpChk1在有性生殖的雌性和雄性中的表达显著高于孤雌生殖的水蚤。整体原位杂交结果表明，DpChk 1在两种繁殖方式下均有表达。孤雌生殖雌虫触角和胸肢中有杂交信号，有性生殖雌虫相应部位的表达水平相对较强，而孤雌生殖雌虫和上海马的性腺中未检测到DpChk 1。总之，这些不同的生殖阶段和性别特异性表达模式的时间和空间调控。我们推测DpChk 1可能参与了D.蚤。
Abstract
The full-length cDNA of a Chk1 gene (DpChk1) was cloned from Daphnia pulex using RACE method. This cDNA is 1767 bp in length, consisting of a 1497 bp open reading frame encoding 498 amino acid protein. The deduced DpChk1 protein sequence contains phosphorylation sites, three conserved Ser-Gln and Thr-Gln motifs and shares 51–55 % similarity with A.pisum, M. rotundata,D. melanogaster, A. echinatior, B. terrestris, R. pulchellus and M. occidentalis, respectively. Gene expression analysis showed that Chk1 is differentially expressed in D. pulex during different reproductive modes. DpChk1 expression in sexually-reproducing females and males is significantly higher than in parthenogenetic Daphnia. Whole-mount in situ hybridization revealed that DpChk1 was expressed during two kinds of reproductive modes. In parthenogenetic females, hybridization signals were found in the antennae and thoracic limb, whereas expression levels in the corresponding sites of sexually-reproducing females were relatively strong, DpChk1 could not be detected in the gonads of ephippial and parthenogenetic females. Taken together, these different reproductive stages and sex specific expression patterns are regulated temporally and spatially. We speculate that DpChk1 may be involved in conversion between different stages of reproduction and in sexual differentiation in D. pulex.