Starvation-induced posttranscriptional control of rat liver mitochondrial citrate carrier expression.

Abstract

Starvation has been associated with a reduced citrate carrier (CTP) activity in rat liver mitochondria. In the present study the molecular mechanism responsible for this reduction was investigated. Northern blot analysis performed with hepatic total RNA showed a decrease of about 40% in the CTP mRNA abundance in starved rats, when compared to fed animals. Nuclear run-on assay did not reveal any appreciable difference in the rate of CTP mRNA synthesis between the two groups of animals, while the apparent half-life of CTP mRNA in hepatocytes from fed and starved rats was 11 and 6h, respectively. Therefore, these results suggest that in starved rats the regulation of hepatic CTP expression occurs at posttranscriptional level. Moreover, the reduced CTP activity in starved animals gradually increased by refeeding. The carrier activity reached fed rat values 6-9h following refeeding. Interestingly, the accumulation of CTP mRNA raised in parallel with the transport activity.

• Authors: Luisa Siculella, Simona Sabetta, Roberta di Summa, Monica Leo, Anna Maria Giudetti, Ferdinando Palmieri, Gabriele Vincenzo Gnoni
• Journal: Biochemical and biophysical research communications (Biochem Biophys Res Commun) Vol. 299 Issue 3 Pg. 418-23 (Dec 06 2002) ISSN: 0006-291X [Print] United States
• PMID: 12445817 (Publication Type: Journal Article)

Chemical References

• Carrier Proteins
• RNA, Messenger
• citrate-binding transport protein

Topics

• Animals
• Carrier Proteins (genetics, metabolism)
• Cell Nucleus (metabolism)
• Hepatocytes (cytology, metabolism)
• Male
• Mitochondria, Liver (metabolism)
• Oxidation-Reduction
• RNA Processing, Post-Transcriptional
• RNA, Messenger (genetics, metabolism)
• Rats
• Rats, Wistar
• Starvation (metabolism)
• Time Factors