TCDB is operated by the Saier Lab Bioinformatics Group
TCIDNameDomainKingdom/PhylumProtein(s)
8.A.51.1.1









The dipeptidyl aminopeptidase-like protein 6, β-subunit, Dpp6, DPPX-S or DPLP (865 aas) of the Kv4.2 K+ channel (TC# 1.A.1.2.5; Dougherty et al. 2009). DPPX-S destabilizes resting and intermediate states in the voltage-dependent activation pathway, which promotes the outward gating charge movement (Dougherty and Covarrubias 2006). It is an auxiliary subunit of A-type voltage-gated K+ channels, and this single transmembrane protein impacts neuronal and synaptic development (Lin et al. 2020).

Eukaryota
Metazoa, Chordata
  Dpp6 of Homo sapiens
8.A.51.1.2









The inactive dipeptidyl peptidase or prolyl oligopeptidase, DPP10 (DPPY, DPRP-3, DPL2, DPPIV  or DPR3) is of 798 aas with 1 N-terminal TMS. It preferentially binds to Kv4 channel proteins to increase current density and alter channel gating (Ren et al. 2005; Zagha et al. 2005). DPP10 also forms complexes with itself and with DPPX in the absence of Kv4 channels. DPP10 mRNA is abundantly expressed in nodose and dorsal root ganglia, suggesting that DPP10 participates in controlling airway reactivity and mechanosensation. The region from the N-terminus to the end of the TMS mediates its association with the channel, whereas the S1-S2 portion of the channel is sufficient for complex formation. This N-terminal portion of DPP10 also confers all the gating effects produced by the peptidase homologue (Ren et al. 2005). DPP10 has an N-terminal DPPIV_N domain and a C-terminal abhydrolase domain. It is an inactivating modulator of Kv4 channels and the Kv1.4 channel (Kuo et al. 2017). DPP10 and KChIP2b (Q9NS61; TC# 8.a.82.2.4) both modulate Kv4.3 inactivation, but their primary effects are on different inactivation states (Kuo et al. 2017).

Eukaryota
Metazoa, Chordata
DPP10 of Homo sapiens
8.A.51.1.3









Dipeptide peptidase, DPP8 of 1452 aas and possibly 3 or 4 TMSs.

Eukaryota
Metazoa, Nematoda
DPP8 of Trichinella patagoniensis
8.A.51.1.4









Peptidase S9B dipeptidylpeptidase IV domain protein of 691 aas

Bacteria
Planctomycetota
Peptidase S9B of Rhodopirellula sp. SWK7
8.A.51.1.5









Dipeptide peptidase 4, DPP4, of 766 aas and 1 or 2 TMSs, one at the N-terminus, and possibly a second near the C-terminus. It has been consdered to be a potential drug target for combating SARS CoV2 (Raghav et al. 2021). There is no upregulation regarding host factors potentially promoting SARS-CoV-2 virus entry into host cells when the SGLT2-blocker empagliflozin, telmisartan and the DPP4-inhibitor blocker, linagliptin, are used (Xiong et al. 2022).

Eukaryota
Metazoa, Chordata
DPP4 of Homo sapiens
8.A.51.1.6









Prolyl endopeptidase, FAP or FAPα; also called melanoma membrane-bound gelatinase and dipeptidyl peptidase  of 760 aas and 2 TMSs, N- and C-terminal.  It plays oncogenic and immunological roles in human cancers (Mai et al. 2023). FAP is a biomarker in colorectal cancer (Kalaei et al. 2023). FAP is a serine protease that has specific endopeptidase activity. It is implicated in diverse cancer-related signaling pathways, contributing to cancer progression, invasion, migration, metastasis, immunosuppression, and resistance to treatment (Cheng et al. 2022).

Eukaryota
Metazoa, Chordata
FAP of Homo sapiens