Structurally distinct and stage-specific adenylyl cyclase genes play different roles in Dictyostelium development.

We have isolated two adenylyl cyclase genes, designated ACA and ACG, from Dictyostelium. The proposed structure for ACA resembles that proposed for mammalian adenylyl cyclases: two large hydrophilic domains and two sets of six transmembrane spans. ACG has a novel structure, reminiscent of the membrane-bound guanylyl cyclases.

A novel arachidonic acid-selective cytosolic PLA2 contains a Ca(2+)-dependent translocation domain with homology to PKC and GAP.

We report the cloning and expression of a cDNA encoding a high molecular weight (85.2 kd) cytosolic phospholipase A2 (cPLA2) that has no detectable sequence homology with the secreted forms of PLA2. We show that cPLA2 selectively cleaves arachidonic acid from natural membrane vesicles and demonstrate that cPLA2 translocates to membrane vesicles in response to physiologically relevant changes in free calcium.

Purification of a 110-kilodalton cytosolic phospholipase A2 from the human monocytic cell line U937.

The major dithiothreitol-resistant phospholipase A2 activity present in the cytosol of U937 cells has been purified greater than 200,000-fold by sequential chromatography on phenyl-5PW, heparin-Sepharose CL-6B, high-performance hydroxylapatite, TSK-gel G3000-SW, and Mono Q columns. This 110-kDa cytosolic phospholipase A2 is distinct from the relatively small (14-kDa) dithiothreitol-sensitive phospholipases A2 that are secreted from many cell types. This additional phospholipase A2 selectively hydrolyzes fatty acid at the sn-2 position of the glycerol and favors phospholipids containing arachidonic acid, which is the rate-limiting precursor for prostaglandin and leukotriene production.

Characterization of a partial cDNA clone for the NILE glycoprotein and identification of the encoded polypeptide domain.

A partial cDNA clone [2.4 kilobase (kb)] for the nerve growth factor-inducible large external (NILE) glycoprotein was selected from a lambda gt11 expression library constructed using mRNA from PC 12 cells. A 0.

Characterization of a partial cDNA clone for the NILE glycoprotein and identification of the encoded polypeptide domain.

A partial cDNA clone [2.4 kilobase (kb)] for the nerve growth factor-inducible large external (NILE) glycoprotein was selected from a lambda gt 11 expression library constructed using mRNA from PC 12 cells. A 0.