by Linjie Wang, Bo Zuo, Dequan Xu, Zuqing Ren, Hongping Zhang, Xuewei Li, Minggang Lei, Yuanzhu Xiong
Background Glycogen synthase kinase 3 (GSK3a and GSK3ß) are serine/threonine kinases involved in numerous cellular processes and diverse diseases including mood disorders, Alzheimer’s disease, diabetes, and cancer. However, in pigs, the information on GSK3 is very limited. Identification and characterization of pig GSK3 are not only important for pig genetic improvement, but also contribute to the understanding and development of porcine models for human disease prevention and treatment.
Methodology Five different isoforms of GSK3ß were identified in porcine different tissues, in which three isoforms are novel. These isoforms had differential expression patterns in the fetal and adult of the porcine different tissues. The mRNA expression level of GSK3ß isoforms was differentially regulated during the course of the insulin treatment, suggesting that different GSK3ß isoforms may have different roles in insulin signaling pathway. Moreover, GSK3ß5 had a different role on regulating the glycogen synthase activity, phosphorylation and the expression of porcine GYS1 and GYS2 gene compared to other GSK3ß isoforms.
Conclusions We are the first to report five different isoforms of GSK3ß identified from the porcine different tissues. Splice variants of GSK3ß exhibit differential activity towards glycogen synthase. These results provide new insight into roles of the GSK3ß on regulating glycogen metabolism.
