Table 1.
Cathepsins in the endo/lysosomal compartment.
| Cathepsin | Enzyme Commission Number | Catalytic Type | Function | Pathology | OMIM ID | Reference |
|---|---|---|---|---|---|---|
| Cathepsin A | 3.4.16.5 | serine | dual function: a. protective:β-galactosidase and neuraminidase b. degradative: bioactive peptides like bradykinin, angiotensin, oxytocin, endothelin 1 |
hypertension Galactosialidosis | 256540 | [63] |
| Cathepsin B | 3.4.22.1 | cysteine | degrades amyloid-β; activation of pro-hormones and pro-enzymes; trypsin activation; promotes viral entry into cells |
Alzheimer’s; gaucher disease acute pancreatitis |
[21,68] | |
| Cathepsin C | 3.4.14.1 | cysteine | inflammatory responses and activation of serine proteases including neutrophil elastase and cathepsin G | Papillon–Lefèvre syndrome Periodontitis |
245000 | [65] |
| Cathepsin D | 3.4.23.5 | aspartic | embryo and neuronal development brain antigen processing of α-Synuclein; tau, amyloid β, apoE; degradation of hormones, proenzymes and growth factors |
Alzheimer’s disease; CLN 10 Parkinson’s; Huntington’s |
610127 | [20,61,64] |
| Cathepsin E | 3.4.23.34 | aspartic | carboxypeptidase A and IgE processing | atopic dermatitis | [71] | |
| Cathepsin F | 3.4.22.41 | cysteine | li chain processing and MHC-II class responses | CLN 13 | 615362 | [63] |
| Cathepsin G | 3.4.21.20 | serine | auto antigen processing | auto-immune diseases | [72] | |
| Cathepsin H | 3.4.22.16 | cysteine | prohormone processing | type 1 diabetes | [9] | |
| Cathepsin K | 3.4.22.38 | cysteine | TLR signaling; processing of β-endorphin in brain | periodontitis; pycnodysostosis | 265800 | [73,74] |
| Cathepsin L | 3.4.22.15 | cysteine | antigen and li chain processing; prohormone processing; degradation of α-Synuclein, tau; promotes viral entry into cells |
Parkinson’s disease; frontotemporal dementia |
[19,49] | |
| Cathepsin S | 3.4.22.27 | cysteine | antigen processing and presentation; li chain processing |
auto-immune diseases | [50] | |
| Cathepsin X | 3.4.18.1 | cysteine | T-cell migration and invasion | - | [75] | |
| Cathepsin O | 3.4.22.42 | cysteine | - | - | ||
| Cathepsin V | 3.4.22.43 | cysteine | natural killer cell and CD8+ cytotoxic cell production | thymic pathology | [76] | |
| Cathepsin W | 3.4.22.- | cysteine | component of endoplasmic reticulum proteolytic machinery | - | [77] | |
| Cathepsin Z | 3.4.18.1 | cysteine | intracellular protein turnover | - | [78] |
- implies that no function or pathology is yet discovered for the respective cathepsins. CLN stands for ceroid lipofuscinosis, neuronal; OMIM stands for online mendelian inheritance in man.