Submitted to: Poultry Science
Publication Type: Abstract Only
Publication Acceptance Date: 6/1/2006
Publication Date: 7/16/2006
Citation: Proszkowiec-Weglarz, M., Richards, M.P., Poch, S.M. 2006. Cloning and expression of chicken AMP-activated protein kinase subunit genes [abstract]. Poultry Science. 85(Supplement 1):75. Paper No. T44.
Technical Abstract: AMP-activated protein kinase (AMPK) is involved in maintaining cellular energy homeostasis and, on the whole animal level, in the regulation of energy balance and food intake. The AMPK enzyme complex consists of one catalytic (alpha) and two regulatory (beta and gamma) subunits. There are two known isoforms for the alpha and the beta subunits and three for the gamma subunit, each of which is encoded by a separate gene. Because so little is known about chicken AMPK subunit genes, the present study was designed to clone, sequence and characterize the seven gene homologues. A molecular cloning strategy involving RT-PCR and 5’-RACE was developed to sequence cDNAs corresponding to complete coding regions and portions of the 5’- and 3’-untranslated regions of chicken AMPK subunit mRNA transcripts. AMPK alpha-1, alpha-2, beta-1 and beta-2 genes code for predicted proteins of 560, 552, 273 and 272 amino acids, respectively. The beta-2 gene produces multiple transcript variants that differ at the 5’-end; however, all code for the same predicted amino acid sequence. The presence or absence of one coding exon in AMPK gamma-1 gene transcripts results in two variants that code for predicted proteins of 298 or 276 amino acids. Use of an alternate promoter and transcription initiation site and/or alternative splicing of gamma-2 gene transcripts results in four different variants that code for predicted proteins of 567, 452, 328 and 158 amino acids. Alternative splicing of exon 3 in the gamma-3 gene results in a shift of the open reading frame and the production of two transcript variants that code for predicted proteins of 382 or 378 amino acids. Each of the AMPK subunit genes exhibited a unique tissue-specific expression pattern. In general, chicken AMPK subunit genes displayed similar structures and high sequence homology as compared to corresponding mammalian genes. Understanding chicken AMPK subunit gene structure and expression patterns provides new insight into the role of the AMPK pathway in metabolic regulation in poultry.