SEQUENCE OF A NOVEL MESSENGER-RNA CODING FOR A C-TERMINAL-TRUNCATED FORM OF HUMAN NAD(-DEPENDENT 15-HYDROXYPROSTAGLANDIN DEHYDROGENASE())

We amplified, using the polymerase chain reaction (PCR) and NAD(+)-dep endent 15-hydroxyprostaglandin dehydrogenase (type-I 15-PGDH)-specific primers, RNA extracted from the HL-60 cell line. Two bands, differing in size by approx. 160 bp, were detected with ethidium bromide staini ng after electrophoresis of amplification products and hybridization w ith a 15-PGDH-specific probe. Sequencing these DNA bands revealed that the largest corresponded to the 15-PGDH cloned from human placenta [E nsor et al., J. Biol. Chem. 265 (1990) 14888-14891]. The smaller seque nce coded for a predicted C-terminal-truncated form of 15-PGDH. This s ubtype of the type-I 15-PGDH mRNA was also found using RT-PCR in human liver, placenta and a cell line derived from a human medullary thyroi d carcinoma (TT cells). Hybridization studies using specific probes in dicated that this new mRNA form probably corresponded to the 3.4-kb mR NA, one of the two 15-PGDH mRNAs previously detected in Northern blot analysis.