PUBLICATION

Sea bass (Dicentrarchus labrax) sex hormone binding globulin: molecular and biochemical properties and phylogenetic comparison of its orthologues in multiple fish species

Authors
Miguel-Queralt, S., Avvakumov, G.V., Blazquez, M., Piferrer, F., and Hammond, G.L.
ID
ZDB-PUB-041229-1
Date
2005
Source
Molecular and Cellular Endocrinology   229(1-2): 21-29 (Journal)
Registered Authors
Keywords
none
MeSH Terms
  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Bass/physiology*
  • CHO Cells/drug effects
  • Cloning, Molecular
  • Cricetinae
  • Databases, Genetic
  • Gonadal Steroid Hormones/pharmacology
  • Kidney/metabolism
  • Liver/metabolism
  • Molecular Sequence Data
  • Phylogeny
  • Rabbits
  • Recombinant Proteins/genetics
  • Recombinant Proteins/immunology
  • Recombinant Proteins/metabolism
  • Sequence Homology, Amino Acid
  • Sex Hormone-Binding Globulin/genetics*
  • Sex Hormone-Binding Globulin/immunology
  • Sex Hormone-Binding Globulin/metabolism*
PubMed
15607525 Full text @ Mol. Cell. Endocrinol.
Abstract
Sex hormone binding globulin (SHBG) binds and transports androgens and estrogens in the blood of vertebrate species including fish. We have used oligonucleotide primers corresponding to highly conserved regions of the SHBG coding sequences within the zebrafish and fugufish genomes to obtain a 1528bp cDNA encoding SHBG from tissue RNA extracts from the European sea bass. Amino-terminal sequence analysis of recombinant sea bass SHBG indicated that its deduced precursor polypeptide includes a 35-residue secretion signal polypeptide, and the 361-residue mature sea bass SHBG sequence exhibits 45-67% sequence identity with SHBGs from other fish species that have been determined directly (for zebrafish) or deduced (for rainbow trout, medaka and fugufish) from sequences within public databases. The sea bass SHBG (39,894Da) comprises a tandem repeat of laminin G-like domains typical of SHBG sequences; contains three N-glycosylation sites, and exists as a 118,300+/-11,500Da homodimer. Sea bass SHBG exhibits a high affinity (K(d)=8.8nM for 17beta-estradiol) and specificity for gonadal steroids and their precursors (e.g., 17beta-estradiol>testosterone>dehydroepiandrosterone>5alpha-dihydrotestosterone>androstenedione>11-ketotesterone). Interestingly, the affinity of sea bass SHBG for the synthetic estrogen, 17alpha-ethynylestradiol was found to be essentially identical to that for 17beta-estradiol. The availability of SHBG sequences in sea bass and other fish set the stage for detailed studies of SHBG function in fish reproductive physiology, as well as its potential role as a target of endocrine disruptors.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping