Trans-regulatory element

Trans-regulatory elements are genes which may modify (or regulate) the expression of distant genes. More specifically, trans-regulatory elements are DNA sequences that encode transcription factors.

Trans-regulatory elements work through an intermolecular interaction between two different molecules and so are said to be "acting in trans". For example (1) a transcribed and translated transcription factor protein derived from the trans-regulatory element; and a (2) DNA regulatory element that is adjacent to the regulated gene. This is in contrast to cis-regulatory elements that work through an intramolecular interaction between different parts of the same molecule: (1) a gene; and (2) an adjacent regulatory element for that gene in the same DNA molecule.

Examples of trans-acting factors include the genes for:

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