Mammalian CDP-diacylglycerol synthase

Abstract

There is disclosed cDNA sequences and polypeptides having the enzyme CDP-diacylglycerol synthase (CDS) activity. CDS is also known as CTP:phosphatidate cytidylyltransferase. There is further disclosed methods for isolation and production of polypeptides involved in phosphatidic acid metabolism and signaling in mammalian cells, in particular, the production of purified forms of CDS.

1 - 16 . (canceled)  
     
     
         17 . An isolated polynucleotide, comprising a polynucleotide sequence selected from the group consisting of: (a) the DNA sequence of SEQ ID NO. 11, (b) a DNA sequence, which encodes the polypeptide of SEQ ID NO. 12 and any biologically active fragments thereof, (c) a DNA sequence that has at least 85% sequence identity to the sequence depicted in SEQ ID NO. 11, and (d) a DNA sequence that has at least 85% sequence identity to a DNA sequence that encodes the polypeptide of SEQ ID NO. 12 or any biologically active fragments thereof, wherein said isolated polynucleotide encodes a polypeptide having cytidine diphosphate diacylglycerol synthase (CDS) activity.  
     
     
         18 . A method of expressing a polypeptide from the polynucleotide that has CDS activity, comprising (a) introducing into a cell the polynucleotide of  claim 17 , wherein said polynucleotide is operably linked to a promoter; and (b) maintaining or growing said cell under conditions that result in the expression of a polypeptide having CDS activity.  
     
     
         19 . The isolated polynucleotide of  claim 17 , wherein said polynucleotide comprises (a) the DNA sequence of SEQ ID NO. 11 or (b) the DNA sequence encoding the polypeptide of SEQ ID NO. 12.  
     
     
         20 . The isolated polynucleotide of  claim 19 , wherein said polynucleotide comprises the DNA sequence of SEQ ID NO. 11.  
     
     
         21 . The isolated polynucleotide of  claim 19 , wherein said polynucleotide comprises the DNA sequence encoding the polypeptide of SEQ ID NO. 12.  
     
     
         22 . An isolated polynucleotide comprising a polynucleotide sequence that hybridizes under high stringency conditions of either (i) incubation in 5×SSC at 65° C., followed by washing in 0.1×SSC for 30 minutes, or (ii) incubation in 50% formamide and 5×SSC at 42° C. to the coding region of the DNA sequence of  claim 19 , wherein said polynucleotide encodes a protein having CDS activity.  
     
     
         23 . An isolated polynucleotide comprising a polynucleotide sequence that hybridizes under high stringency conditions of either (i) incubation in 5×SSC at 65° C., followed by washing in 0.1×SSC for 30 minutes, or (ii) incubation in 50% formamide and 5×SSC at 42° C. to the complement of the DNA sequence depicted in SEQ ID NO. 11, wherein said polynucleotide encodes a protein having CDS activity.  
     
     
         24 . The isolated polynucleotide of  claim 17 , wherein said polynucleotide encodes a full-length CDS polypeptide.