Help:Translational units/Glossary

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Head Domain

The Head domain consists of the ribosome binding sites and a start codon followed immediately by zero or more triplets specifiying an N-terminal tag, such as a protein export tag or lipoprotein binding tag. Examples of head domains include

  • RBS plus start codon
  • RBS, start codon and codons 2-3
  • RBS, start codon and signal sequence
  • RBS, start codon and affinity tag

Internal Domains

Protein domains consist of a series of codon triplets coding for an amino acid sequence without a start codon or stop codon. Multiple Domains can be fused together. Examples of internal domains include

  • DNA binding domains
  • Dimerization domains
  • Kinase domains

Special Internal Domains are short domains with specific function may be separately categorized, but obey the same composition rules as normal domains. Examples of special internal domains include

  • Linkers
  • Cleavage sites
  • Inteins

Tail Domain

The C-terminus of a coding region consists of zero or more triplet codons, followed by a pair of TAA stop codons. In the simplest case, the stop codons terrminate the protein with an Stop. More complex Tails may include degradation tags appropriate to the organism (i.e., with different degradation rates). Examples of Tail domain include

  • Stop codon
  • A degradation tag followed by a stop codon
  • An affinity tag followed by a stop codon