Slowed transcription and rapid messenger RNA turnover contribute to a decline in synthesis of ovine trophoblast protein-1 during in vitro culture

Journal Article · Mon Jul 01 00:00:00 EDT 1991 · Biology of Reproduction; (United States)

DOI:https://doi.org/10.1095/biolreprod45.1.94· OSTI ID:5031891

Hansen, T R; Cross, J C; Farin, C E; Imakawa, K; Roberts, R M ^[1]

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1. Department of Animal Sciences, University of Missouri, Columbia (United States)

Ovine trophoblast protein-1 (oTP-1) is produced in massive amounts by conceptuses during the Day-12-20-period of early pregnancy. The rate of production of oTP-1 declines during culture of conceptuses, however, suggesting a role for critical intrauterine factors for continued production. The present study was conducted to define the mechanism responsible for the in vitro decline in oTP-1 synthesis. Over 24 h culture, synthesis of oTP-1 was initially rapid but then declined such that there was little increase in either the protein or its antiviral activity after 12 h. By contrast, the release of total protein into the medium continued at an approximately linear rate for the entire 24-h period of culture. By using in situ hybridization to tissue sections and dot-blot analysis of tissue extracts with labeled cDNA probes, it was shown that the quantity of oTP-1 mRNA fell 3- to 5-fold during culture, whereas the amount of actin mRNA remained relatively constant. To determine whether this selective fall in levels of oTP-1 mRNA resulted from decreased transcription rate and/or high turnover rate of existing mRNA, conceptuses were either provided continuously with (3H)uridine for 24 h or labeled for 9 h and then exposed to medium enriched in unlabeled uridine and cytidine for a further 15 h. Specific incorporation of 3H into oTP-1 mRNA was assessed by hybridization to excess oTP-1 cDNA immobilized on nitrocellulose membranes. In the continuous labeling study, 3H in total RNA increased at an approximately linear rate for at least 18 h, whereas the content of 3H in oTP-1 mRNA peaked at 9 h and declined about 10-fold by 24 h.

• OSTI ID: 5031891
• Journal Information: Biology of Reproduction; (United States), Vol. 45:1; ISSN 0006-3363
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
DNA
BIOASSAY
MESSENGER-RNA
METABOLISM
PROTEINS
BIOSYNTHESIS
BIOLOGICAL HALF-LIFE
CELL CULTURES
DNA HYBRIDIZATION
PREGNANCY
SHEEP
TRACER TECHNIQUES
TRANSCRIPTION
TRITIUM COMPOUNDS
URIDINE
ANIMALS
AZINES
DOMESTIC ANIMALS
HETEROCYCLIC COMPOUNDS
HYBRIDIZATION
HYDROGEN COMPOUNDS
HYDROXY COMPOUNDS
ISOTOPE APPLICATIONS
MAMMALS
NUCLEIC ACIDS
NUCLEOSIDES
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PYRIMIDINES
RIBOSIDES
RNA
RUMINANTS
SYNTHESIS
URACILS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques