Duel of the fates: the role of transcriptional circuits and noise in CD4+ cells

► In CD4+ T cells changes in cellular fate are precise yet contain stochastic elements. ► Cell-to-cell variation in abundance of molecules represents 'noise.' ► Sources of noise include transcription, network topology and signaling environments. ► Transcriptional noise may include leaky expression of lowly expressed transcripts. ► Epigenetic marks (e.g. bivalent histone marks) may correlate with gene noise profiles.