Cloning of equine interleukin 1 receptor antagonist and determination of its full-length cDNA sequence.
OBJECTIVE
To clone equine interleukin 1 receptor antagonist (IL-1ra) and determine its full-length cDNA sequence.


METHODS
A cDNA library derived from lipopolysaccharide-stimulated equine monocytes was screened by means of plaque hybridization to radiolabeled equine IL-1ra DNA probes generated by means of the polymerase chain reaction. The cDNA nucleotide sequence for equine IL-1ra was determined by use of the dideoxy chain termination technique, analyzed by use of computer software for sequence characteristics, and compared with sequences reported for IL-1ra of other species.


RESULTS
The cDNA of equine IL-1ra was 1,614 base pairs in length with an ORF encoding a peptide of 177 amino acids with a predicted molecular mass of 20.427 kd. Similarity between the amino acid sequence of equine IL-1ra and sequences for human, murine, rat, and lapine IL-1ra was 76%. Similarity between sequence for equine IL-1ra and sequences for equine interleukin-1 alpha and equine interleukin-1 beta were 22.6 and 24.6%, respectively.


CONCLUSIONS
Comparison of the sequence for equine IL-1ra with sequences for IL-1ra of other species indicated a high degree of conservation.


CONCLUSIONS
Results establish a basis for studying the roles of interleukin-1 in healthy and diseased joints in horses.
Howard
R D
RD
Department of Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins 80523, USA.
McIlwraith
C W
CW
Trotter
G W
GW
Nyborg
J K
JK
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D003001:Cloning, Molecular; D015342:DNA Probes; D018076:DNA, Complementary; D015723:Gene Library; D006736:Horses; D006801:Humans; D053590:Interleukin 1 Receptor Antagonist Protein; D051379:Mice; D008969:Molecular Sequence Data; D009000:Monocytes / Q000276:immunology; D016133:Polymerase Chain Reaction; D011817:Rabbits; D051381:Rats; D017472:Receptors, Interleukin-1 / Q000037:antagonists & inhibitors; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D012795:Sialoglycoproteins / Q000096:biosynthesis* / Q000737:chemistry
D015342:DNA Probes; D018076:DNA, Complementary; C507763:IL1RN protein, human; C507764:Il1rn protein, mouse; D053590:Interleukin 1 Receptor Antagonist Protein; D017472:Receptors, Interleukin-1; D011994:Recombinant Proteins; D012795:Sialoglycoproteins