Alternative splicing of the porcine glycogen synthase kinase 3β (GSK-3β) gene with differential expression patterns and regulatory functions.
BACKGROUND
Glycogen synthase kinase 3 (GSK3α and GSK3β) 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.


METHODS
Five different isoforms of GSK3β 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 GSK3β isoforms was differentially regulated during the course of the insulin treatment, suggesting that different GSK3β isoforms may have different roles in insulin signaling pathway. Moreover, GSK3β5 had a different role on regulating the glycogen synthase activity, phosphorylation and the expression of porcine GYS1 and GYS2 gene compared to other GSK3β isoforms.


CONCLUSIONS
We are the first to report five different isoforms of GSK3β identified from the porcine different tissues. Splice variants of GSK3β exhibit differential activity towards glycogen synthase. These results provide new insight into roles of the GSK3β on regulating glycogen metabolism.
Institute of Animal Genetics and Breeding, Sichuan Agricultural University, Ya'an, Sichuan, People's Republic of China. wanglinjie@sicau.edu.cn
Linjie
L
Wang
Bo
B
Zuo
Dequan
D
Xu
Zuqing
Z
Ren
Hongping
H
Zhang
Xuewei
X
Li
Minggang
M
Lei
Yuanzhu
Y
Xiong
D017398:Alternative Splicing; D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D004847:Epithelial Cells / Q000201:enzymology; D005260:Female; D015870:Gene Expression; D015971:Gene Expression Regulation, Enzymologic; D006006:Glycogen Synthase / Q000235:genetics / Q000378:metabolism; D038362:Glycogen Synthase Kinase 3 / Q000235:genetics* / Q000378:metabolism; D000071679:Glycogen Synthase Kinase 3 beta; D007328:Insulin / Q000494:pharmacology / Q000502:physiology; D008297:Male; D008969:Molecular Sequence Data; D009928:Organ Specificity; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D021381:Protein Transport; D016415:Sequence Alignment; D034421:Sus scrofa / Q000235:genetics* / Q000378:metabolism
D007328:Insulin; D020033:Protein Isoforms; D006006:Glycogen Synthase; C000605506:GSK3B protein, human; D000071679:Glycogen Synthase Kinase 3 beta; D038362:Glycogen Synthase Kinase 3