Table 3.
GMVs are enriched for many proteins involved in glomerular biology.
| Glomerular Protein | Uniprot Swiss Prot ID |
Gene Name |
Coverage in Fraction C (%) |
Peptid e Count |
Localization | Previously seen in ELVs |
Comments | Referenc e |
|---|---|---|---|---|---|---|---|---|
| Podocalyxin | PODXL_HUMAN B7ZKQ8 |
Podocalyxin-like | 25 | 12 | Podocyte | NHLBI | Abundant protein in GMVs. Creates negative charge on secondary podocyte foot processes. | 28, 29 |
| Lysosomal associated membrane protein 2 LAMP2 | LAMP2_HUMAN P13473 |
LAMP2 | 14 | 5 | - | H, NHLBI | Proposed autoantigen role in pauciimmune glomerulonephritis and Henoch-Schönlein purpura. | 94, 95 |
| Src substrate cortactin | SRC8_HUMAN Q14247 |
CTTN | 44 | 22 | Podocyte | Mediates interaction between podocalyxin and actin filaments. Interacts with PODXL. | 96 | |
| Rab 23 | SRC8_HUMAN Q9ULC3 |
RAB23 | 47 | 9 | Podocyte | Hogan | Expressed in the glomerulus. | 97 |
| ENPP6 | ENPP6_HUMAN Q6UWR7 |
ENPP6 | 53 | 17 | - | H, NHLBI | Known secreted protein; mechanism hitherto unknown. Candidate biomarker of rat diabetic nephropathy. | 4,98 |
| Ezrin | EZRI_HUMAN P15311 |
EZR | 73 | 62 | Podocyte | Yes | Glomerular epithelial cell marker in glomerulogenesis. | 99 |
| Complement C4B | CO4B_HUMAN P0C0L5 |
C4B | 4 | 6 | Glomerular capillary endothelial cells | W | Susceptibility to SLE. Complement C4 is made in vivo in glomerular capillary endothelium cells | 61,62 |
| Agrin | AGRIN_HUMAN O00468 |
AGRN | 9 | 17 | GBM | No | Probable human glomerular permselectivity modulator. May anchor GBM to cytoskeleton. A major heparan sulfate proteoglycan. | 87, 88 |
| FAT4 | AGRIN_HUMAN Q6V0I7 |
FAT4 | 0.8 | 2 | Podocyte | H | Fat 4 −/− mice have small kidneys and develop cystic disease. Expressed in glomeruli-involved in planar cell polarity. | 100 |
| CD59 | CD59_HUMAN P13987 |
CD59 | 26 | 6 | - | W, NHLBI | Complement regulatory protein that inhibits the terminal part of the complement system-membrane attack complex (MAC). | 101 |
| Talin 1 | TLN1_HUMAN Q9Y490 |
TLN1 | 8 | 14 | Glomerulus | W, NHLBI | Adaptor proteins that connect the integrin family of cell adhesion receptors to cytoskeletal actin. | 102 |
| Syntenin 1 | SDCB1_HUMAN O00560 |
SDCBP | 86 | 38 | - | NHLBI | Adaptor protein in apical endocytic pathway-top ranked protein in our data by percentage coverage. | 103 |
| Neprilysin (neutral endopeptidase) | NEP_HUMAN P08473 |
CD10 | 71 | 79 | Podocyte | W | Protease that cleaves ACE. Induces human membranous glomerulonephritis in neonates cases of membranous nephropathy in newborns from neutral endopeptidase-deficient mothers. | 104, 105 |
| Na(+)/H(+) exchange regulatory cofactor 2 | NHRF2_HUMAN Q15599 |
SLC9A3R2 | 14 | 3 | Podocyte | NHLBI (1 peptide) | Podocyte cytoskeleton connects to podocalyxin through this protein. | 106 |
| Angiotensin-converting enzyme 2 | ACE2_HUMAN Q9BYF1 |
ACE2 | 30 | 19 | Podocyte | NHLBI | Present in podocyte foot processes. | 107, 108 |
| Angiotensin-converting enzyme | ACE_HUMAN P12821 |
ACE | 72 | 54 | Endothelial cells | NHLBI | Traverses from capillary endothelial cells to podocytes. | 108 |