Single molecule adventures in the life of a single cell

Traditionally, we believe that genes are regulated via trans acting factors like transcription factors interacting with local cis regulatory elements encoded in the DNA itself. The potential for long-range regulation, however, raises the potential for far more complex modes of transcriptional control. Through the use of new single molecule RNA imaging techniques to examine gene expression in individual cells, we explored non-local regulation of transcription. Examples include chromosome-wide transcriptional changes induced by chromosomal translocation and transcriptional regulation by long non-coding RNA. We also discuss some results global regulation of transcription for cellular homeostasis. Our results reveal how the cell solves a number of problems related to DNA content and force a reinterpretation of single cell gene expression measurements.