Transcription factor stoichiometry in cell fate determination.

Transcription factors play very important role in cell fate determination. There are many cell specific transcription factors which when expressed ectopically may lead to cell fate conversion or transdifferentiation. Many of these transcription factors function differently based on their levels and stoichiometry. Many different types of differentiated cells have been generated from other differentiated cell types by expressing different levels and stoichiometry of reprogramming factors. Many methodologies have been developed for efficient cell fate conversion by regulating the levels and stoichiometry of transcription factors in a particular cocktail that have therapeutic values. An approach called phenotypic activation which involves overexpression of putative transcription factors has been developed as a tool to discover new transcription factors and their targets. Transcription factor overexpression may also have toxic effects where nonspecific electrostatic interactions and 'squelching' may lead to inhibition of many genes. Altered levels of transcription factors may have disastrous consequences like cancer. Recent developments like designing of artificial transcription factors, nanotechnology-based transcriptional tools and CRISPR-based transcription modules with capabilities of precise regulation of gene expression patterns hold huge potentials in the field of transcriptional therapeutics.