Submitted to: Plant and Animal Genome Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: November 1, 2005
Publication Date: January 14, 2006
Citation: Proszkowiec-Weglarz, M., Richards, M.P., McMurtry, J.P. 2006. Molecular cloning and characterizaton of chicken AMP-activated protein kinase gamma subunit genes [abstract]. Plant and Animal Genome IV. P. 241. Abstract Number P557.
AMP-activated protein kinase (AMPK) is involved in the regulation of cellular energy homeostasis and, on the whole animal level, in regulating energy balance and food intake. The AMPK enzyme complex consists of one catalytic (alpha) and two regulatory (beta and gamma) subunits. Previously, we found that chickens expressed three gamma subunits (gamma 1-3), each encoded by a different gene. The objective of this study was to characterize chicken AMPK gamma gene expression. A molecular cloning strategy involving primer-directed RT-PCR and 3’- and 5’-RACE was developed to sequence chicken cDNAs corresponding to complete coding regions and portions of the 5’- and 3’-untranslated regions of AMPK gamma-1, -2 and -3 mRNA transcripts. The presence or absence of one exon by alternative splicing of the gamma-1 gene resulted in two transcript variants which code for predicted proteins containing 298 amino acids (4 cystathionine beta-synthase domains, CBSD) or 276 amino acids (3 CBSD). For the gamma-2 gene, use of an alternate initiation site and promoter and/or alternative splicing resulted in four different transcript variants which code for predicted proteins containing 567 (4 CBSD), 452 (4 CBSD), 328 (3 CBSD) and 158 (2 CBSD) amino acids. Alternative splicing of exon 3 in the gamma-3 gene resulted in a shift of the open reading frame and the production of ‘long’ and ‘short’ transcript variants that code for predicted proteins of 383 and 363 amino acids, both with 4 CBSD. Chicken gamma genes displayed similar structures and high sequence homology compared to corresponding mammalian gamma gene homologues.