Relationship between Ca2+ and lasparagine in the induction of ornithine decarboxylase in H-35 rat hepatoma cells

K. P. Hau*, P. C.L. Wong, David W F FONG

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)

Abstract

The activity of ornithine decarboxylase (ODC) in H-35 hepatoma cells depleted of Ca2+ by washing with 2 mM EGTA increased 35-fold after incubating for 4h in a simple salt-glucose solution containing 10 mM L-asparagine and only if Ca2+ was replenished. Actinomycin D (5 μg/ml) and cycloheximide (20 μM) reduced the stimulatory effect by 84 and 100% respectively. Increase of active enzyme protein was also demonstrated by a 3-fold increase in α-difluoromethylornithine binding. Asparagine prolonged the half-life of induced ODC by 20% whereas Ca2+ reduced it by 32%. The observed inductive effects are not accounted for entirely by a direct influence of Ca2+ and asparagine on the turnover of ODC protein. These factors are likely to be parts of a signalling pathway leading to amplification of cellular ODC.

Original languageEnglish
Pages (from-to)169-179
Number of pages11
JournalBiochemistry International
Volume28
Issue number1
Publication statusPublished - 1992

Scopus Subject Areas

  • Biochemistry

Fingerprint

Dive into the research topics of 'Relationship between Ca<sup>2+</sup> and lasparagine in the induction of ornithine decarboxylase in H-35 rat hepatoma cells'. Together they form a unique fingerprint.

Cite this