Expression profiling of skeletal muscle in beef cattle treated with steroidal growth promoters

ABSTRACT: In the present study, a oligonucleotide microarray platform is used to compare expression profiles of beef cattle muscle in animals treated with either Dexamethazone (Dex) or Dexamethazone plus 17?-estradiol (Estr) administered at sub-therapeutic dosage, against untreated controls. Seventeen male beef cattle 15-18 months old, around 450 kg mean body weight were randomly allocated in three groups: 6 were untreated (group Ctrl), 5 were administered with dexamethazone via feed 0.75mg/head for 43 days (group D); the last 6 animals were administered via feed for 43 days with Dex (0.75mg/head) and intramuscularly (i.m.) for three times with 17?-oestradiol, 20mg/head, (group DE). Three additional control animals, matching in sex and age, collected in a previous experiment were included in the Ctrl group to increase sample size and to control for biological variation. For each sample, total RNA was extracted from a specific anterior limb muscle (biceps branchii). Data analysis demonstrates that the expression profiles were strongly affected by Dex treatment with hundreds of genes up-regulated with relevant fold-change, whereas the myostatin gene was significantly down-regulated. On the contrary, the administration of Dex-Estr reveals a weaker effect on gene expression. In this study, we analyzed the gene expression profiles of 20 anterior limb muscle samples, 9 collected from untreated controls, 5 collected from cattle treated with Dex and 6 from cattle treated with Dex+Estr using Agilent-015354 Bovine oligo microarray platform (20 arrays, no replicate) based on single-colour detection (Cyanine-3 only). Microarrays are scanned with Agilent scanner G2565BA (barcode on the left, DNA on the back surface, scanned through the glass) at a resolution of 5 microns; all slides are scanned twice at two different sensitivity settings (XDRHi 100% and XDRLo 10%); the scanner software creates a unique ID for each pair of XDR scans and saves it to both scan image files. Feature Extraction 9.5 uses XDR ID to link the pairs of scans together automatically when extracting data. The signal left after all the FE processing steps have been completed is ProcessedSignal that contains the Multiplicatively Detrended, Background-Subtracted Signal

ORGANISM(S): Bos taurus

SUBMITTER: Serena Ferraresso 

PROVIDER: E-GEOD-12179 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress