Expression profiling reveals meiotic male germ cell mRNAs that are translationally up- and down-regulated
Expression profiling reveals meiotic male germ cell mRNAs that are translationally up- and down-regulated
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DOI：
10.1073/pnas.0510999103
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发表时间：
2006-05-16
影响因子：
11.1
通讯作者：
Hecht, Norman B.
中科院分区：
文献类型：
--
作者：
Iguchi, Naoko;Tobias, John W.;Hecht, Norman B.
配子在很大程度上依赖于转录后控制机制来调节其分化。在卵子中，母体mRNA被储存并在发育过程中被选择性激活。在男性中，转录在精子发生过程中停止，需要对精子组装和功能所需的许多父系mRNA进行转录后调节。到目前为止，大多数已知的睾丸mRNA是在减数分裂后的细胞中转录的。由于蛋白质合成发生在多核糖体上，并且无活性的mRNA被隔离为核糖核蛋白（RNP），因此mRNA在这些组分之间的移动指示翻译上调和下调。在这里，我们使用微阵列来分析mRNA的RNP和多聚核糖体从睾丸提取物的青春期前和成年小鼠的精子发生过程中的翻译状态的特点。与已发表的报告一致，许多延迟减数分裂后的mRNA从RNP转移到多核糖体中，建立了这种方法的有效性。此外，我们还检测到另外742个小鼠睾丸转录物，这些转录物在RNP和多聚核糖体之间显示出巨大的变化。一个包含已知的延迟磷酸甘油酸激酶2（Pgk2）的35个基因的亚组最初在减数分裂期间转录，并在后期细胞中翻译。另一个82个减数分裂表达基因的亚组在精子发生后期被抑制性下调。这种高通量方法定义了雄性生殖细胞分化时基因群体的翻译模式的变化，并确定了减数分裂转录本的上调和下调。
Gametes rely heavily on posttranscriptional control mechanisms to regulate their differentiation. In eggs, maternal mRNAs are stored and selectively activated during development. In the male, transcription ceases during spermiogenesis, necessitating the posttranscriptional regulation of many paternal mRNAs required for spermatozoan assembly and function. To date, most of the testicular mRNAs known to be translationally regulated are initially transcribed in postmeiotic cells. Because protein synthesis occurs on polysomes and translationally inactive mRNAs are sequestered as ribonucleoproteins (RNPs), movement of mRNAs between these fractions is indicative of translational up- and down-regulation. Here, we use microarrays to analyze mRNAs in RNPs and polysomes from testis extracts of prepuberal and adult mice to characterize the translation state of individual mRNAs as spermatogenesis proceeds. Consistent with published reports, many of the translationally delayed postmeiotic mRNAs shift from the RNPs into the polysomes, establishing the validity of this approach. In addition, we detect another 742 mouse testicular transcripts that show dramatic shifts between RNPs and polysomes. One subgroup of 35 genes containing the known, translationally delayed phosphoglycerate kinase 2 (Pgk2) is initially transcribed during meiosis and is translated in later-stage cells. Another subgroup of 82 meiotically expressed genes is translationally down-regulated late in spermatogenesis. This high-throughput approach defines the changing translation patterns of populations of genes as male germ cells differentiate and identifies groups of meiotic transcripts that are translationally up- and down-regulated.