Changing patterns of gene expression in Dictyostelium prestalk cell subtypes recognized by in situ hybridization with genes from microarray analyses
Changing patterns of gene expression in Dictyostelium prestalk cell subtypes recognized by in situ hybridization with genes from microarray analyses
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DOI：
10.1128/ec.2.3.627-637.2003
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发表时间：
2003-06-01
期刊：
影响因子：
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通讯作者：
Loomis, WF
中科院分区：
文献类型：
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作者：
Maeda, M;Sakamoto, H;Loomis, WF
我们使用微阵列携带大多数的基因，在发育调控的网骨藻发现那些优先表达的prestalk细胞。前柄细胞位于蛞蝓的前部，在蛞蝓的形态发生和迁移过程中起着重要作用。使用整装原位杂交，我们能够验证104 prestalk基因。其中三个被发现只在蛞蝓最前面的细胞中表达，即PstA细胞类型。另外10个基因被发现在少数细胞中表达，这些细胞在前部形成一个中心核心，即PstAB细胞类型。其余的prestalk特异性基因在PstO细胞中表达，PstO细胞位于PstA细胞的后面，但位于80%由前孢子细胞组成的蛞蝓的前面。其中一半也在PstA细胞中表达。在发育的后期，这些前茎基因的表达模式发生了显著变化，使我们能够进一步细分它们。有些在高潮期间以高得多的水平表达，而另一些则被抑制。这些结果证明了在网骨藻中细胞类型特异性表达的极其动态的性质，并进一步定义了细胞类型的变化生理学。影响PstO细胞中基因表达的信号之一是六苯酮DIF-1。我们发现，在不能合成DIF-1的突变体中，大约一半的PstO特异性基因的表达受到影响，而其余的似乎是DIF独立的。这些结果表明，PstO细胞的某些方面的分化可以在DIF-1不存在的情况下发生。
We used microarrays carrying most of the genes that are developmentally regulated in Dictyostelium to discover those that are preferentially expressed in prestalk cells. Prestalk cells are localized at the front of slugs and play crucial roles in morphogenesis and slug migration. Using whole-mount in situ hybridization, we were able to verify 104 prestalk genes. Three of these were found to be expressed only in cells at the very front of slugs, the PstA cell type. Another 10 genes were found to be expressed in the small number of cells that form a central core at the anterior, the PstAB cell type. The rest of the prestalk-specific genes are expressed in PstO cells, which are found immediately posterior to PstA cells but anterior to 80% of the slug that consists of prespore cells. Half of these are also expressed in PstA cells. At later stages of development, the patterns of expression of a considerable number of these prestalk genes changes significantly, allowing us to further subdivide them. Some are expressed at much higher levels during culmination, while others are repressed. These results demonstrate the extremely dynamic nature of cell-type-specific expression in Dictyostelium and further define the changing physiology of the cell types. One of the signals that affect gene expression in PstO cells is the hexaphenone DIF-1. We found that expression of about half of the PstO-specific genes were affected in a mutant that is unable to synthesize DIF-1, while the rest appeared to be DIF independent. These results indicate that differentiation of some aspects of PstO cells can occur in the absence of DIF-1.