Pre-beta-HDL stimulates placental lactogen release from human trophoblast cells.

To examine whether pre-beta-high-density lipoprotein (HDL) may be involved in regulation of human placental lactogen (hPL) release, pre-beta-HDL was isolated from term pregnancy serum, and the effect of purified pre-beta-HDL on hPL release from trophoblast cells was examined after 1 h of exposure. Pre-beta-HDL stimulated a dose-dependent increase in hPL release with half-maximal stimulation at a dose of 300-400 microgram/ml, which is within the normal physiological range during pregnancy. Analysis of pre-beta-HDL and alpha-HDL in serum from pregnant women at different stages of gestation (determined by Western blot analysis) indicated that the pre-beta-HDL-to-alpha-HDL ratio increased linearly after the 10th week of gestation (r = 0.

Apolipoprotein A-I stimulates placental lactogen expression by human trophoblast cells.

Earlier studies from our laboratory indicated that apolipoprotein A-I (Apo A-I) stimulates the acute release of human placental lactogen (hPL) from trophoblast cells in culture. We have now demonstrated that Apo A-I also causes a secondary increase in hPL release, beginning about 6 h after exposure to Apo A-I, that is blocked by cycloheximide and actinomycin D. Apo A-I also stimulated a dose-dependent increase in hPL promoter activity in JAR cells transfected with a 1.

Isolation and structural characterization of the bovine tyrosine hydroxylase gene.

A bovine tyrosine hydroxylase (TH) cDNA probe was used to screen a charon 30 genomic library. Screening of approximately 1 million recombinant phage resulted in the identification of one clone, lambda B1, containing the entire bovine TH gene. Results derived from restriction endonuclease mapping and sequence analysis reveal that the bovine gene contains 13 exons spanning approximately 7 kb of genomic DNA.

Isolation and nucleotide sequence of a cDNA clone encoding bovine adrenal tyrosine hydroxylase: comparative analysis of tyrosine hydroxylase gene products.

Investigations into the structure and mechanisms regulating the expression of the genes involved in catecholamine biosynthesis have led to the isolation of a cDNA coding for bovine adrenal tyrosine hydroxylase (TH). The 1,722 bp cDNA contains the complete coding sequence and 3' untranslated region of the TH mRNA. The nucleotide sequence of the cDNA and the deduced amino acid sequence were compared to those reported for rat and human TH.

The complete nucleotide sequence and structure of the gene encoding bovine phenylethanolamine N-methyltransferase.

A cDNA clone for bovine adrenal phenylethanolamine N-methyltransferase (PNMT) was used to screen a Charon 28 genomic library. One phage was identified, designated lambda P1, which included the entire PNMT gene. Construction of a restriction map, with subsequent Southern blot analysis, allowed the identification of exon-containing fragments.