How much complexity is being concealed by doing research on gene regulation and function in a limited range of biological contexts? Experiments have to start somewhere, and confirmation of results in a couple of additional systems can lead to the assumption that observations are 'generalizable'. But several articles in this issue remind us that biology is rarely simple, and studies in multiple contexts often reveal a fuller picture.
The proteins that recognize the core elements of gene promoters were long thought to be passive, structural components shared by all genes that are transcribed by RNA polymerase II. In a Review on p549, Goodrich and Tjian explain how this view came from experiments in a limited range of cell systems. By contrast, recent analysis in specific cell types at different developmental stages has revealed these proteins to be dynamic participants in transcriptional regulation. The value of looking at many cell types and developmental stages is also highlighted by recent work that has revealed hundreds of new examples of genomic imprinting (In Brief, p528).
This is a preview of subscription content, access via your institution
