Dipeptidyl peptidase 9 is an enzyme that in humans is encoded by the DPP9gene.
This gene encodes a protein that is a member of the S9B family in clan SC of the serine proteases. The protein has been shown to have post-proline dipeptidyl aminopeptidase activity, cleaving Xaa-Pro dipeptides from the N-termini of proteins. Although the activity of this protein is similar to that of dipeptidyl peptidase 4 (DPP4), it does not appear to be membrane bound. In general, dipeptidyl peptidases appear to be involved in the regulation of the activity of their substrates and have been linked to a variety of diseases including type 2 diabetes, obesity and cancer. Several transcript variants of this gene have been described but not fully characterized.
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