Please use this identifier to cite or link to this item:
Scopus Web of Science® Altmetric
Type: Journal article
Title: Evolution of marsupial and other vertebrate thyroxine-binding plasma proteins
Author: Richardson, S.
Bradley, A.
Duan, W.
Wettenhall, R.
Harms, P.
Babon, J.
Southwell, B.
Nicol, S.
Donnellan, S.
Schreiber, G.
Citation: American Journal of Physiology, 1994; 266(4):R1359-R1370
Publisher: American Physiological Society
Issue Date: 1994
ISSN: 0002-9513
Statement of
Samantha J. Richardson, Adrian J. Bradley, Wei Duan, Richard E. Wettenhall, Paul J. Harms, Jeffrey J. Babon, Bridget R. Southwell, Stewart Nicol, Stephen C. Donnellan, and Gerhard Schreiber
Abstract: Binding of radioactive thyroxine to proteins in the plasma of vertebrates was studied by electrophoresis followed by autoradiography. Albumin was found to be a thyroxine carrier in the blood of all studied fish, amphibians, reptiles, monotremes, marsupials, eutherians (placental mammals), and birds. Thyroxine binding to transthyretin was detected in the blood of eutherians, diprotodont marsupials, and birds, but not in blood from fish, toads, reptiles, monotremes, and Australian polyprotodont marsupials. Globulins binding thyroxine were only observed in the plasma of some mammals. Apparently, albumin is the phylogenetically oldest thyroxine carrier in vertebrate blood. Transthyretin gene expression in the liver developed in parallel, and independently, in the evolutionary lineages leading to eutherians, to diprotodont marsupials, and to birds. In contrast, high transthyretin mRNA levels, strong synthesis, and secretion of transthyretin in choroid plexus from reptiles and birds indicate that transthyretin gene expression in the choroid plexus evolved much earlier than in the liver, probably at the stage of the stem reptiles. NH2-terminal sequence analysis suggests a change of transthyretin pre-mRNA splicing during evolution.
Keywords: Albumin; transthyretin; prealbumin; thyroxine-binding globulin; fish; amphibians; reptiles; monotremes; placental mammals; birds; amino acid sequence; gene expression; liver; transport; choroid plexus; RNA splicing; eutherians
Rights: Copyright © 1994 the American Physiological Society. All rights reserved.
DOI: 10.1152/ajpregu.1994.266.4.r1359
Appears in Collections:Aurora harvest 8
Earth and Environmental Sciences publications

Files in This Item:
There are no files associated with this item.

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.