nephrocystin-1; Juvenile nephronophthisis 1 protein (NPHP1, NPH1)

Function

• together with Cas it may play a role in the control of epithelial cell polarity
• seems to help to recruit protein tyrosine kinase-2 beta (PTK2B) to cell matrix adhesions, thereby initiating phosphorylation of PTK2B & PTK2B-dependent signaling
• interacts with Crk-associated substrate (Cas), NPHP4, PTK2B & tensin
• interacts with INVS & NPHP3

Structure

• the SH3 domain mediates the stable interaction with Cas
• belongs to the nephrocystin-1 family
• contains 1 SH3 domain

Compartment

• cell junction, adherens junction
• localizes at or near the cell-cell adherens junctions (putative)

Alternative splicing

named isoforms=4

Expression

• widespread expression
• highest levels in pituitary gland, spinal cord, thyroid gland, testis, skeletal muscle, lymph node & trachea
• weakly expressed in heart, kidney & pancreas

Pathology

• defects in NPHP1 are the cause of:
  • nephronophthisis type 1
  • Senior-Loken syndrome
  • Joubert syndrome type 4

More general terms

• nephrocystin

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=4867
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:4867
• OMIM: https://mirror.omim.org/entry/256100
• OMIM: https://mirror.omim.org/entry/266900
• OMIM: https://mirror.omim.org/entry/607100
• OMIM: https://mirror.omim.org/entry/609583
• UniProt: http://www.uniprot.org/uniprot/O15259.html