Evaluation of gene expression in pigs selected for enhanced reproduction using differential display PCR. II. Anterior pituitary

• Published in: Journal of animal science 2004, Vol.82 (1), p.32-40
• Main Authors: Bertani, G.R, Gladney, C.D, Johnson, R.K, Pomp, D
• Format: Article
• Language: English
• Subjects: Animal productions; Animals; Biological and medical sciences; Blotting, Northern - veterinary; Dinoprost - pharmacology; Female; Ferritins - genetics; Ferritins - metabolism; Follicle Stimulating Hormone, beta Subunit - genetics; Follicle Stimulating Hormone, beta Subunit - metabolism; Fundamental and applied biological sciences. Psychology; Gene Expression; GTP-Binding Protein beta Subunits - genetics; GTP-Binding Protein beta Subunits - metabolism; line differences; Molecular Sequence Data; Peptide Fragments - genetics; Peptide Fragments - metabolism; Pituitary Gland, Anterior - metabolism; polymerase chain reaction; Polymerase Chain Reaction - methods; Polymerase Chain Reaction - veterinary; Random Allocation; Reproduction - genetics; selection criteria; Selection, Genetic; Swine - genetics; Swine - physiology; Terrestrial animal productions; Vertebrates
• ISSN: 0021-8812; 1525-3163
• DOI: 10.2527/2004.82132x

The objective of this study was to identify differentially expressed genes in the anterior pituitary (AP) of sows selected for enhanced reproductive phenotypes. Selection in the Index (I) line was based on an index of ovulation rate and embryo survival, whereas random selection was used in the Control (C) line. Average numbers of fully formed piglets at birth were 12.5 +/- 1.5 and 9.9 +/- 2.0 for Line I and C sows used in this study, respectively. In order to induce luteolysis and synchronize follicle development, sows were injected (i.m.) with 2 mL of prostaglandin F2alpha analog between d 12 and 14 of the estrous cycle. Tissue was harvested 2 d (d2) or 4 d (d4) after injection, resulting in four experimental groups: Cd2 (n = 6), Cd4 (n = 4), Id2 (n = 6), and Id4 (n = 7). Differential display PCR (ddPCR) was used to search for transcriptional changes between selection lines in the AP, using samples within line but pooled across days. Northern hybridization was used to confirm ddPCR results. For ddPCR, two pools were used from each line (C and I). Three genes were confirmed to be differentially expressed between Lines I and C: G-beta like protein, ferritin heavy-chain, and follicle stimulating hormone beta subunit, whereas many other expressed sequence tags were observed to be differentially expressed but still require confirmation. Our findings indicate that long-term selection to increase ovulation rate and decrease embryo mortality has altered transcriptional patterns in the anterior pituitary, most likely as correlated responses.