Cloning, Sequence Analysis, And Expression Characteristics Of The Duck Akirin2Gene In Tissues And Myoblast

Akirin gene is a newly nuclear protein factor interacting in regulating gene expression and signalling cascades in innate immune, myogenic and carcinogenic pathways. Akirin, a single protoorthologue duplicated in the vertebrates, before the gnathostome-agnathan separation, producing Akirinl and Akirin2, occursing functional divergence in paralogues.In vertebrates, Akirinl was named mighty in mice and was shown to regulate myogenesis, enhanced and accelerated differentiation of myoblasts and hypertrophy of myotubes.Most importantly, Akirinl overexpression leads to increased and earlier expression of MyoD and MyoG, and increased secretion of another known differentiation inducing factor,1GF-Ⅱ. Whereas Akirin2was characterised as FBI1in rats and acted together with or downstream of NF-kB in the control of TLR and IL-1β inducible gene expression.But, no akirinl orthologue was present in the current Ensembl genome assembly, the absence of Akirinl in Gallus gallus, zebra finch and turkey reflects the genuine loss of a gene family member. If the function of akirin1in amniote muscle growth is essential, then its absence in birds, where muscle physiology is strongly conserved with mammals, particularly in terms of the functions of key genes, could only be fulfilled by akirin2. In order to study the functions of Akirin2, we cloned duck Akirin2gene, and studied the expression of Akirin2in differentiatin tissues.In this study, the relative expression levels of Akirin2gene in leg muscle and myoblasts was studied by real-time PCR. The results showed that:1. We cloned duck Akirin2gene about1154bp for the first time, and the coding domain sequence (CDS) contain594bp, encoding197amino acids. Homology analysis showed that Akirin2sequence is highly conserved among species.2. Amino acid sequence analysis revealed that Akirin2gene amino acid sequence conservated in mammals, but there was amino acid variation between birds and mammals. N-terminal and C-terminal of Akirin2were highly conserved.3. Expression level of Akirin2among different tissues are greatly various in forty-day ducks. Akirin2expressed in leg muscle at highest level (p<0.05), while in breast muscle at lowest level (p<0.05).4. Study the developmental expression patterns of Akirin2gene in breast muscle during embryonic development stages. The expression level of Akirin2decreased with age growth, which express the highest (p<0.05) on the tenth day, and reached its loeest value on the twenty-seven day. 5. Transcript expression pattern of Akirin2during the development of myoblasts culture. Akirin2showed lower expression levels in mononuclear cells (day2-3), when myoblasts are in the generation stage.And higher levels at day4-6, when myoblasts are in the differentiation stage.6. The Akirin2expression profile is compared to equivalent qPCR data for a range of other genes (MyoG, Myf6, MCK, MyoD, Myf5, Desmin). Akirin2, MyoG, Myf6, MCK are in the same one cluster, and MyoD, Myf5, Desmin are in the other one. Akirin2shared highly significant positive co-expression patterns with MyoG and Myf6.