| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Animal Sciences, University of Illinois, Urbana, Illinois, United States
* To whom correspondence should be addressed. E-mail: jloor{at}uiuc.edu.
Achieving greater understanding of the genomic influence on milk synthesis in dairy cows represents a daunting challenge. Bovine-specific microarrays have allowed high-throughput gene expression analysis of the mammary transcriptome. However, real-time PCR (qPCR) still represents the method of choice for accurate expression profiling of small numbers of genes and verification of key microarray relationships. This method is extremely sensitive but requires data normalization to account for analytical errors. Ideally, expression of genes used as internal controls should not be affected by specific treatments or physiological state. Mammary biopsies were collected from five cows each at -15, 1, 15, 30, 60, 120, and 240 days relative to parturition for gene expression profiling. We evaluated expression of nine genes (RPS9, ACTB, GAPD, GTP, ITGB4BP, MRPL39, RPS23, RPS15, and UXT) that could serve as internal controls in mammary tissue using qPCR. Due to gradual increases in mammary RNA concentration (µg/mg tissue) over lactation, all genes investigated experienced a dilution effect. We used pairwise comparison of expression ratios to analyze the reliability of these genes as internal controls. UXT, RPS9, and RPS15 had the most stable expression ratios across cow and time. We also assessed co-regulation among genes through network analysis. Network analysis suggested co-regulation among most of the genes examined, with MYC playing a central role. Pairwise comparison was suitable for finding appropriate internal controls in mammary gland tissue. Results showed that the geometrical average of UXT, RPS9, and RPS15 expression could be used as internal control for longitudinal mammary gene expression profiling.
This article has been cited by other articles:
|
|
 |
|
  J-Q. He, A. J. Sandford, I-M. Wang, S. Stepaniants, D. A. Knight, A. Kicic, S. M. Stick, and P. D. Pare Selection of housekeeping genes for real-time PCR in atopic human bronchial epithelial cells Eur. Respir. J., September 1, 2008; 32(3): 755 - 762. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Tramontana, M. Bionaz, A. Sharma, D. E. Graugnard, E. A. Cutler, P. Ajmone-Marsan, W. L. Hurley, and J. J. Loor Internal Controls for Quantitative Polymerase Chain Reaction of Swine Mammary Glands During Pregnancy and Lactation J Dairy Sci, August 1, 2008; 91(8): 3057 - 3066. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. Bionaz and J. J. Loor ACSL1, AGPAT6, FABP3, LPIN1, and SLC27A6 Are the Most Abundant Isoforms in Bovine Mammary Tissue and Their Expression Is Affected by Stage of Lactation J. Nutr., June 1, 2008; 138(6): 1019 - 1024. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. Piantoni, M. Bionaz, D. E. Graugnard, K. M. Daniels, R. M. Akers, and J. J. Loor Gene Expression Ratio Stability Evaluation in Prepubertal Bovine Mammary Tissue from Calves Fed Different Milk Replacers Reveals Novel Internal Controls for Quantitative Polymerase Chain Reaction J. Nutr., June 1, 2008; 138(6): 1158 - 1164. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. J. Loor, R. E. Everts, M. Bionaz, H. M. Dann, D. E. Morin, R. Oliveira, S. L. Rodriguez-Zas, J. K. Drackley, and H. A. Lewin Nutrition-induced ketosis alters metabolic and signaling gene networks in liver of periparturient dairy cows Physiol Genomics, December 19, 2007; 32(1): 105 - 116. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Ringseis, C. Dathe, A. Muschick, C. Brandsch, and K. Eder Oxidized Fat Reduces Milk Triacylglycerol Concentrations by Inhibiting Gene Expression of Lipoprotein Lipase and Fatty Acid Transporters in the Mammary Gland of Rats J. Nutr., September 1, 2007; 137(9): 2056 - 2061. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
