For most peptides this planar form is about 1000 times more stable than the alternative, unless the second residue is proline, in which case it is only about 4 times more stable.  
Dominant mutations described by this prefix often involve genes that encode diffusible factors, such as the wild-type lacI+ gene.  Monocistronic mRNAs are produced from polycistronic primary transcripts in trypanosomes by this type of splicing, which combines a short leader exon and any of several independent coding exons.  For most peptides this planar form is about 1000 times more stable than the alternative, unless the second residue is proline, in which case it is only about 4 times more stable.  As a result, in most native proteins the C O and N H groups point in opposite directions, as indicated by, FTP, what configurational prefix contrasted with cis?
Dominant mutations described by this prefix often involve genes that encode diffusible factors, such as the wild-type lacI+ gene.  
Trans