Sphingomyelin Phosphodiesterase, Acid Like 3A (SMPDL3A)

Using yeast 2-hybrid analysis with the sequence of the DBCCR1 gene as query to screen a human bladder cDNA library, Wright et al. (2002) identified SMPDL3A. The 454-amino acid protein has a predicted molecular mass of 51.2 kD.

Transient transfection of SMPDL3A and DBCCR1 in bladder tumor cells resulted in overexpression of DBCCR1 and upregulation of SMPDL3A mRNA and protein. Only full-length DBCCR1 increased SMPDL3A expression, suggesting that the membrane attack complex/perforin domain of the N terminus of DBCCR1 is not sufficient for SMPDL3A interaction. SMPDL3A expression was increased in 8 of 12 bladder tumor specimens and only detectable in 1 corresponding normal urothelium specimen.