Cis-regulatory element

As a cis- element or cis- acting element (from Latin cis, cis ') is in biology a particular section in the genetic information called, which plays a role in the regulation of a gene located on the same DNA molecule as this ( molecular considered on this side ). This regulatory sequence section must not be RNA or protein and can be encoded in the read direction, before or after the coding sequence of the respective gene, or within ( in an intron ).

Cis- elements upstream of a gene often represent necessary binding motifs for (specific ) transcription factors that intervene here as a trans -acting elements (from the Latin trans, beyond ') molecular seen by others in the regulation of transcription of this gene. Lead cis elements about an inhibition of transcription, they are termed silencers. Cis - elements that lead to an enhancement of transcription are called enhancers. The whole promoter in the cis-/trans-Aktivitäten finally determines the degree to which the RNA polymerase is carried out transcription.

For example, in tumors inducing Ti plasmid of Agrobacterium cis- elements in the form of repetitive sequences to find ( repeat motif of 25 bases ), which in the annular plasmid as a left or right border ( left border (LB ) and right border ( RB) ), the T-DNA flank. They are regarded as essential cis-elements for the transfer of T-DNA during the transfer into the plant cell.