Lactase synthesis is pretranslationally regulated in protein-deficient pigs fed a protein-sufficient diet

Mary A. Dudley, Patricia A. Schoknecht, Alden W. Dudley, Lan Jiang, Ronaldo Ferraris, Judy N. Rosenberger, Joseph F. Henry, Peter J. Reeds

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

The in vivo effects of protein malnutrition and protein rehabilitation on lactase phlorizin hydrolase (LPH) synthesis were examined. Five-day-old pigs were fed isocaloric diets containing 10% (deficient, n = 12) or 24% (sufficient, n = 12) protein. After 4 wk, one-half of the animals in each dietary group were infused intravenously with [13C1]leucine for 6 h, and the jejunum was analyzed for enzyme activity, mRNA abundance, and LPH polypeptide isotopic enrichment. The remaining animals were fed the protein-sufficient diet for 1 wk, and the jejunum was analyzed. Jejunal mass and lactase enzyme activity per jejunum were significantly lower in protein-deficient vs. control animals but returned to normal with rehabilitation. Protein malnutrition did not affect LPH mRNA abundance relative to elongation factor-1α, but rehabilitation resulted in a significant increase in LPH mRNA relative abundance. Protein malnutrition significantly lowered the LPH fractional synthesis rate (FSR; %/day), whereas the FSR of LPH in rehabilitated and control animals was similar. These results suggest that protein malnutrition decreases LPH synthesis by altering posttranslational events, whereas the jejunum responds to rehabilitation by increasing LPH mRNA relative abundance, suggesting pretranslational regulation.

Original languageEnglish (US)
JournalAmerican Journal of Physiology - Gastrointestinal and Liver Physiology
Volume280
Issue number4 43-4
StatePublished - Apr 1 2001

Fingerprint

Lactase-Phlorizin Hydrolase
Lactase
Swine
Diet
Jejunum
Malnutrition
Proteins
Rehabilitation
Messenger RNA
Peptide Elongation Factor 1
Enzymes
Leucine

All Science Journal Classification (ASJC) codes

  • Gastroenterology
  • Physiology (medical)
  • Physiology
  • Hepatology

Keywords

  • Fractional and total synthesis rates
  • Gas chromatography-mass spectroscopy
  • Messenger ribonucleic acid
  • Small intestine

Cite this

Dudley, Mary A. ; Schoknecht, Patricia A. ; Dudley, Alden W. ; Jiang, Lan ; Ferraris, Ronaldo ; Rosenberger, Judy N. ; Henry, Joseph F. ; Reeds, Peter J. / Lactase synthesis is pretranslationally regulated in protein-deficient pigs fed a protein-sufficient diet. In: American Journal of Physiology - Gastrointestinal and Liver Physiology. 2001 ; Vol. 280, No. 4 43-4.
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Lactase synthesis is pretranslationally regulated in protein-deficient pigs fed a protein-sufficient diet. / Dudley, Mary A.; Schoknecht, Patricia A.; Dudley, Alden W.; Jiang, Lan; Ferraris, Ronaldo; Rosenberger, Judy N.; Henry, Joseph F.; Reeds, Peter J.

In: American Journal of Physiology - Gastrointestinal and Liver Physiology, Vol. 280, No. 4 43-4, 01.04.2001.

Research output: Contribution to journalArticle

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AU - Dudley, Mary A.

AU - Schoknecht, Patricia A.

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