The primary structure of a protein, the sequence of its amino acids, is determined by the sequence of nucleotides in DNA through the processes of transcription and translation. The 'Central Dogma' is the framework for understanding the transfer of sequence information from DNA to protein. In the eukaryotic model, transcription of DNA produces the primary transcript which is processed further by alternative splicing to produce the final mRNA. Translation of the mRNA on ribosomes produces the polypeptide chain which may or may not require further post-translational modification to give rise to the mature protein. Structural proteins frequently exhibit regularities in their amino acid sequence, but this tends not to be the case with globular proteins.