FIGURE 6.

Mapping of the NLD fragments that are needed for secretion and catalytic activity. A, using specific primer sets, a series of NPP2 proteins with varying NLD fragments was obtained. Expression and secretion of these constructs was monitored by immunoblotting with c-Myc antibodies (Ab). Tubulin was used as an internal control for equal loading. Next, immunoblotting was repeated to determine equal amounts of these proteins in the cell lysate (B) and the medium (C), and these volumes were used to measure the corresponding lysophospholipase-D (LPase D) activities. The bar diagrams show the means of three independent experiments (±S.E.). PDase, phosphodiesterase.