CLoning of equine interleukin 1 alpha and equine interleukin 1 beta and determination of their full-length cDNA sequences.

The research is about the successful cloning and sequencing of horse versions of two important immune system proteins, Interleukin 1 alpha (IL-1 alpha) and Interleukin 1 beta (IL-1 beta). This lays the groundwork for studying the role of these proteins in joint health and diseases in horses.

Methodology

• The research used mRNA samples gathered from cultured horse monocytes that were stimulated with lipopolysaccharide, a trigger for immune response.
• From these mRNA samples, a complementary DNA (cDNA) library was constructed using a lambda phage, a type of virus used in research for DNA manipulation and cloning.
• To find the relevant equine IL-1 alpha and IL-1 beta cDNA within the library, the researchers screened the library using radiolabeled cDNA probes for human IL-1 alpha and IL-1 beta.
• The identified equine IL-1 alpha and IL-1 beta cDNAs were sequenced using the dideoxy chain termination technique, a method used to reveal the specific order of nucleotide bases in a DNA molecule.

Results

• The cDNA for equine IL-1 alpha was found to be 1,728 base pairs long and encoded a protein consisting of 270 amino acids. The predicted size of the protein was approximately 30.823 kilodaltons (kd).
• The cDNA for equine IL-1 beta was shorter, at 1,473 base pairs, encoding a slightly smaller protein of 268 amino acids with a predicted molecular mass around 30.342 kd.
• The similarity of these equine proteins to their counterparts in other species was also determined. Equine IL-1 alpha and IL-1 beta shared 62.5 to 82.2% similarity to other species’ IL-1 alpha and beta sequences respectively.
• However, the similarity between equine IL-1 alpha and IL-1 beta themselves was only 26%.

Conclusion

• The research, therefore, successful in establishing the full-length cDNA sequences of both equine IL-1 alpha and equine IL-1 beta.
• This provides a critical foundation for further studies to understand the involvement of interleukin 1 proteins in maintaining good health and disease conditions in horses, particularly in their joints.