Identification of a parathyroid hormone in the fish Fugu rubripes.
A PTH gene has been isolated from the fish Fugu rubripes. The encoded protein of 80 amino acid has the lowest homology with any of the PTH family members. Fugu PTH(1-34) had 5-fold lower potency than human PTH(1-34) in a mammalian cell system.


BACKGROUND
Parathyroid hormone (PTH) is the major hypercalcemic hormone in higher vertebrates. Fish lack parathyroid glands, but there have numerous attempts to identify and isolate PTH from fish.


METHODS
Polymerase chain reaction (PCR) was performed with primers based on preliminary data from the Joint Genome Institute database. PCR amplification was performed on genomic DNA isolated from Fugu rubripes. PCR products were purified and DNA was sequenced. All sequence was confirmed from more than one independently amplified PCR product. Multiple sequence alignments were carried out, and the percentage of identities and similarities were calculated. An unrooted phylogenetic tree, using all the known PTH and PTH-related protein (PTHrP) amino acid sequences, was determined. Synthetic peptides were tested in a biological assay that measured cyclic adenosine 3',5'-monophosphate formation in UMR106.1 cells. Rabbit polyclonal antisera specific for N-terminal human PTHrP and one rabbit polyclonal antiserum specific for N terminus hPTH were used to test the cross-reactivity with fPTH(1-34) in immunoblots.
Danks
Janine A
JA
St Vincent's Institute of Medical Research, Fitzroy, Victoria, Australia. j.danks@unimelb.edu.au
Ho
Patricia M W
PM
Notini
Amanda J
AJ
Katsis
Frosa
F
Hoffmann
Peter
P
Kemp
Bruce E
BE
Martin
T John
TJ
Zajac
Jeffrey D
JD
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D019143:Evolution, Molecular; D006801:Humans; D008969:Molecular Sequence Data; D010281:Parathyroid Hormone / Q000032:analysis* / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D023741:Takifugu / Q000235:genetics*
D010281:Parathyroid Hormone