Temperature Acclimation of Enzyme Activities and Protein Synthesis in Channel Catfish (Ictalurus Punctatus). In Vivo and In Vitro Studies
Koban, Michael
This item is only available for download by members of the University of Illinois community. Students, faculty, and staff at the U of I may log in with your NetID and password to view the item. If you are trying to access an Illinois-restricted dissertation or thesis, you can request a copy through your library's Inter-Library Loan office or purchase a copy directly from ProQuest.
Permalink
https://hdl.handle.net/2142/71432
Description
Title
Temperature Acclimation of Enzyme Activities and Protein Synthesis in Channel Catfish (Ictalurus Punctatus). In Vivo and In Vitro Studies
Author(s)
Koban, Michael
Issue Date
1984
Department of Study
Physiology and Biophysics
Discipline
Physiology
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Biology, General
Abstract
Hepatocytes from 15(DEGREES)C acclimated catfish isolated by collagenase perfusion were maintained for 3-4 weeks in primary culture at 7, 15, and 25(DEGREES)C on biomatrix prepared from liver structural proteins. Specific activities of enzymes of cultured hepatocytes showed acclimatory compensation for the following: cytochrome(DEGREES)C oxidase, citrate synthase, NADH-cytochrome(DEGREES)C reductase, and glucose-6-phosphate dehydrogenase. Lactate dehydrogenase showed no compensation. 6-phosphogluconate dehydrogenase showed partial inverse compensation. Hence, cultured hepatocytes show temperature acclimation of enzymes in patterns similar to those measured in vivo. Protein synthesis measured at 15(DEGREES)C by hepatocytes from catfish acclimated to different temperatures occurred in the series: 7 > 15 > 25(DEGREES)C acclimation. Protein synthesis measured at 15(DEGREES)C by cultured hepatocytes occurred in the series: 15 > 7 > 25(DEGREES)C. Protein degradation measured at temperatures of culture occurred in the series: 25 > 15 > 7(DEGREES)C. Changes in concentration of enzymes during acclimation may occur by direct temperature effects on rates of synthesis and degradation, and differences in temperature effects on protein synthesis in vitro and in vivo may result from absence of some critical substance in culture.
In fluorographs of two-dimensional gel electrophoresis many polypeptides increased or decreased synthesis rates during low temperature acclimation; others did not change.
The effect of temperature acclimation on heat-shock protein (hsp) synthesis was examined in hepatocytes isolated from catfish acclimated to 7 and 25(DEGREES)C. In 7(DEGREES)C acclimated fish hsp was maximal at 25-35(DEGREES)C, hsp of 25(DEGREES) at 35(DEGREES)C. Hsp is synthesized at lower temperatures by cold acclimated than by warm acclimated fish.
Temperature acclimation of metabolic enzymes can occur in isolated cells in patterns similar to those in vivo. Temperature acclimation of protein synthesis in cultured cells follows a pattern different from that in intact fish. Temperature acclimation of protein synthesis is selective for specific proteins of mitochondria. Synthesis of heat-shock proteins can be altered by temperature acclimation.
Use this login method if you
don't
have an
@illinois.edu
email address.
(Oops, I do have one)
IDEALS migrated to a new platform on June 23, 2022. If you created
your account prior to this date, you will have to reset your password
using the forgot-password link below.
