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Measuring Lactase Enzymatic Activity in the Teaching Lab
Published on: August 6, 2018
Native and recombinant bovine placental lactogens
Andrea V Alvarez-Oxiley1, Noelita M de Sousa, Jean-François Beckers
1Laboratory of Animal Endocrinology and Reproduction, Faculty of Veterinary Medicine, University of Liege, Bd. de Colonster, 4000. Liege, Belgium.
Reproductive Biology
|August 5, 2008
Summary
Bovine placental lactogen (bPL), a hormone similar to pituitary proteins, plays roles in pregnancy and fetal development. Its varying forms and concentrations suggest targeted functions in bovine reproduction.
Area of Science:
- Reproductive Biology
- Endocrinology
- Protein Chemistry
Background:
- The bovine placenta synthesizes proteins analogous to pituitary hormones from the GH/PRL gene family.
- Bovine placental lactogen (bPL) is a glycoprotein hormone with both lactogenic and somatogenic activities.
Purpose of the Study:
- To characterize bovine placental lactogen (bPL), including its molecular properties, isoforms, and physiological roles.
- To investigate the expression and potential functions of bPL during bovine pregnancy.
Main Methods:
- Analysis of bPL molecular mass and isoelectric variants in placental extracts and fetal sera.
- Description of bPL mRNA transcription sites and timing during gestation.
- Review of known maternal and fetal roles of bPL.
Main Results:
- Purified native bPL molecules have apparent molecular masses (31-33 kDa) exceeding their protein core's theoretical mass.
- Multiple bPL isoelectric variants and isoforms exist, with more acidic forms found in circulation, suggesting glycosylation.
- bPL mRNA is transcribed from Day 30 of gestation until term in trophectoderm binucleate cells.
Conclusions:
- Bovine placental lactogen (bPL) exhibits complex molecular heterogeneity and is expressed throughout bovine pregnancy.
- bPL is implicated in maternal reproductive functions and nutrient supply to the fetus.
- Higher fetal concentrations suggest bPL primarily targets fetal tissues, influencing development.
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