Mehdy M C, Ratner D, Firtel R A
Cell. 1983 Mar;32(3):763-71. doi: 10.1016/0092-8674(83)90062-4.
We have identified genes that are expressed preferentially in either prestalk or prespore cells in Dictyostelium. The prestalk mRNAs are detectable at 7.5 hr prior to the completion of cell aggregation, while the prespore mRNAs are not detectable until approximately 15 hr of development. Exogenous cAMP in the absence of sustained cell contact is sufficient to induce prestalk-specific gene expression, while multicellularity is required for the induction of prespore-specific genes. A gene expressed equally in both cell types, which has the same developmental kinetics as the prestalk genes, is induced in shaking culture in the absence of either cAMP or stable cell associations. Dissociation of aggregates results in the rapid loss of prespore- and prestalk-specific mRNAs, and these can be induced to reaccumulate with the addition of cAMP. We conclude that there are substantial differences in the timing and requirements for tissue-specific gene expression in Dictyostelium.
我们已经鉴定出在盘基网柄菌的前柄细胞或前孢子细胞中优先表达的基因。在前柄细胞聚集完成前7.5小时就能检测到前柄mRNA，而前孢子mRNA直到发育约15小时后才能检测到。在没有持续细胞接触的情况下，外源性环磷酸腺苷（cAMP）足以诱导前柄特异性基因表达，而诱导前孢子特异性基因则需要多细胞性。在一种在两种细胞类型中均等量表达的基因中，其具有与前柄基因相同的发育动力学，在没有cAMP或稳定细胞关联的摇瓶培养中被诱导表达。聚集体的解离导致前孢子和前柄特异性mRNA迅速丢失，并且添加cAMP后这些mRNA可以被诱导重新积累。我们得出结论，盘基网柄菌中组织特异性基因表达的时间和要求存在显著差异。
