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Spatial and temporal pattern of cellular myc oncogene expression in developing human placenta: implications for embryonic cell proliferation.

S Pfeifer-Ohlsson·A S Goustin·J Rydnert·T Wahlström·L Bjersing·D Stehelin·R Ohlsson
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Abstract

We have analyzed staged human placentas by Northern, dot blot, and in situ hybridization to human c-myc probes. Placental RNA exhibits a stage-specific appearance of a 2.4 kb transcript of the c-myc gene. The frequency of this transcript varies 20 to 30 fold over the course of placental development, showing a peak at 4-5 weeks after conception, where the myc transcripts comprise about 0.05% by weight of the total placental mRNA. A clear decline in placental c-myc transcription is seen before the end of the first trimester of pregnancy. In situ hybridization to 125I-labeled myc probes demonstrates an unequal spatial distribution of myc transcripts in placental with particularly high expression in the cytotrophoblastic shell of early placenta. Labeling of placental explants with 3H-thymidine, the localization of myc transcripts to cytotrophoblasts, and the temporal pattern of myc expression all support a strong correlation between myc transcript abundance and cytotrophoblast proliferation. We argue for a role for the c-myc gene in the proliferation of normal cells in this tissue.

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Cell DivisionFemaleGene Expression RegulationHumansNucleic Acid HybridizationOncogenesPlacentaPregnancyRNA, MessengerTissue DistributionTranscription, GeneticTrophoblastsJournal ArticleResearch Support, Non-U.S. Gov't

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S Pfeifer-Ohlsson, A S Goustin, J Rydnert, T Wahlström, L Bjersing, D Stehelin, R Ohlsson. 1984. Spatial and temporal pattern of cellular myc oncogene expression in developing human placenta: implications for embryonic cell proliferation.. https://doi.org/10.1016/0092-8674(84)90513-0

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