Molecular cloning and sequence analysis of the gene encoding interleukin‐6 of the giant panda (Ailuropoda melanoleuca)

Abstract

In the present study, the cloning and sequence analysis of interleukin‐6 (IL‐6) from the giant panda (Ailuropoda melanoleuca) were described. Sequencing revealed that IL‐6 complementary DNA contains a 636 base‐pair open reading frame encoding 211 amino acids. Homology analyses indicated that the identity levels of nucleotide and deduced amino acid sequences of IL‐6 between the giant panda and other species in Carnivora ranged from 90.5% to 85.6% and from 82.9% to 76.5%, respectively. Phylogenetic analyses based on nucleotide and amino acid sequences showed that the harbour seal shared a closer relationship with the giant panda than other carnivores (ursids not included). The functionally important domains and sites that have previously been recognized in other carnivores were all observed in the IL‐6 sequence of the giant panda. These findings suggest that the complementary DNA fragment cloned is indeed the IL‐6 molecule with biological activity and can be used in immunological studies of the giant panda.

Keywords:

• Ailuropoda melanoleuca
• interleukin‐6
• complementary DNA sequence
• phylogeny

Acknowledgements

This research work was funded by a grant from Chengdu Giant Panda Breeding Research Foundation. The authors are grateful to Chengdu Research Base of Giant Panda Breeding for providing the samples of giant panda blood.

Liu Xu and Bo Zeng contributed equally to this work.