Fig. 1
From: Insulins for the long term management of diabetes mellitus in dogs: a review
A The sequence of the canine pre-proinsulin (predicted from ensembl.org; transcript: ENSCAFT00000016041.5). B Cleavage of the signal and c-peptides results in the formation of the mature insulin peptide. C The sequence of human insulin is identical to canine insulin except for a single amino acid difference at position B30 (threonine (T) replacing alanine (A)). The black lines represent the position of the disulphide bonds. Note: The figure does not accurately represent the tertiary structure of insulin which is complex and variable