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Analysis of Epididymal Protein Synthesis and Secretion
Published on: August 25, 2018
Apoprotein synthesis by human duodenojejunal mucosa
Gastroenterology
|October 1, 1978
Summary
Human duodenojejunal mucosa synthesizes apoproteins A-I, A-II, and B from amino acid precursors. This study confirms the intestine
Area of Science:
- Gastroenterology
- Molecular Biology
- Biochemistry
Background:
- Lipoprotein-like particles observed in human absorptive cells suggest apoprotein synthesis.
- Apoproteins are known to be synthesized by the perfused rat intestine.
Purpose of the Study:
- To investigate the capacity of human duodenojejunal mucosa to synthesize apoproteins from amino acid precursors.
- To identify specific apoproteins synthesized in vitro by human intestinal tissue.
Main Methods:
- Incubation of human duodenojejunal biopsies with L-[U-14C]leucine.
- Fractionation of biopsy homogenates using ultracentrifugation.
- Immunoprecipitation of incorporated radioactivity using antibodies against human apoproteins A-I, A-II, and B.
Main Results:
- Significant incorporation of [14C]leucine into proteins within duodenojejunal biopsies.
- Majority of incorporated radioactivity localized in the d < 1.006 fraction, indicative of lipoprotein particles.
- Specific precipitation of radioactivity by antibodies against apoproteins A-I, A-II, and B, confirming their synthesis.
Conclusions:
- Human duodenojejunal mucosa possesses the capability to synthesize apoproteins A-I, A-II, and B from amino acid precursors in vitro.
- The findings support the role of the human intestine in apoprotein synthesis and lipoprotein assembly.
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