ARS | Publication request: Linkage Mapping of the Channel Catfish Proopiomelanocortin (POMC) Gene

Submitted to: Animal Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 9, 2005
Publication Date: April 1, 2005
Citation: Karsi, A., Waldbieser, G.C. 2005. Linkage Mapping of the Channel Catfish Proopiomelanocortin (POMC) Gene. Animal Genetics 36:171-173.

Interpretive Summary: Proopiomelanocortin (POMC) is an important protein determining the function of the hypothalamic– pituitary–adrenal axis, the main mediator of the stress response. In the pituitary of mammalian species, lobe-specific processing and post-translational modifications of the precursor protein yield biologically active peptides including adrenocorticotropic hormone (ACTH), melanocyte stimulating hormones (MSH) and b-endorphin (b-EP). POMC-derived peptides play important physiological roles, including background adaptation, energy balance, stress response and obesity. The objective of the present study was to map the channel catfish POMC gene by linkage analysis. A polymorphic microsatellite locus was identified in a POMC gene intron, and catfish populations showed six alleles for this gene. Inheritance of POMC alleles in two reference families showed it was most closely linked with two anonymous genetic markers on linkage group 13. The POMC gene is well conserved in vertebrates and placement of POMC on the catfish genetic linkage map will assist investigators in comparisons of the catfish genome with the genomes of other vertebrates.

Technical Abstract: Proopiomelanocortin (POMC) is an important protein determining the function of the hypothalamic– pituitary–adrenal axis, the main mediator of the stress response. In the pituitary of mammalian species, lobe-specific processing and post-translational modifications of the precursor protein yield biologically active peptides including adrenocorticotropic hormone (ACTH), melanocyte stimulating hormones (MSH) and b-endorphin (b-EP). POMC-derived peptides play important physiological roles, including background adaptation, energy balance, stress response and obesity. The objective of the present study was to map the channel catfish POMC gene by linkage analysis. A microsatellite locus was identified within intron 3 of the POMC gene, and six alleles were identified in catfish populations. Twopoint linkage analysis identified the most significant linkage of POMC with marker IpCG0037 (LOD = 17) in linkage group U13. Multi-point linkage analysis placed POMC 10.9 cM from the terminal marker IpCG0104 on the basis of 137 informative meioses.