A mechanism that couples DNA transposition to cell differentiation (hypothesis).

A hypothesis underlying the significance of cytoplasmic events in the process of DNA transposition is proposed. To appear at a new chromosomal site, the transposon sequence is assumed to be first transcribed and then, in a form of the RNA copy, transported to the cytoplasm. A translation-dependent selection of RNA transcripts for reverse transcription is then made and the resulting single-stranded DNA copies return to the nucleus. The free copy may integrate within a new, transcriptionally inactive region of the chromosomal DNA. As a net result, cell differentiation advances in a manner coupled to the message utilization. The hypothesis finds support in many observations, particularly those made for plant cells.