Transcriptional responses

Between 5,000 and 100,000 GR molecules are found within almost every cell of the organism. The affinity constant for cortisol comes to around 30 nM, which is in the range of the concentration of free hormone in the plasma under normal conditions. Consequently, receptor occupancy can be expected to be 10-70%. This suggests that changes in cortisol secretion such as under stress conditions, directly translate into alterations in GR occupancy, leading to transcriptional responses. 

Horvath CM (2000) STAT proteins and transcriptional responses to extracellular signals. Trends Biochem Sci 25 496-502... 

Herschman, H.R. (1989). Extracellular signals, transcriptional responses and cellular specificity. Trends Biochem. Sci, 14, 455—458. 

As more is learned about the chromosomal effects on HS gene expression, it is important to point out that these genes are actually a subset of inducible responses to cellular stress. Not all of these inducible responses involve HSF, and this indicates that cells have diversified transcriptional responses to cope with different types of stress. This diversification is manifested by glucose regulated genes (grp), as well as the metallothionein and oxidant-injury genes (Watswich, 1988 Storz et al., 1990 Devary et al., 1992 Skroch et al., 1993 Xu, 1993). 

Lee, L.J., Barrett, J.A., and Poole, R.K., Genome-wide transcriptional response of chemostat-cultured Escherichia coli to zinc, J Bacteriol, 187 (3), 1124-1134, 2005. 

Worden, C., Kovac, W., Dorn, L., and Sandrin, T., Environmental pH affects transcriptional responses to cadmium toxicity in Escherichia coli K-12 (MG1655), FEMS Microbiol Lett, 293 (1), 58-64, 2009. 

Belcher CE et al. The transcriptional responses of respiratory epithelial cells to BordeteUa pertussis reveal host defensive and pathogen counter-defensive strategies. Proc Natl Acad Sci USA 2000 97 13847-13852. 

Lanahan A et al. Selective alteration of long-term potentiation-induced transcriptional response in hippocampus of aged, memory-impaired rats. J Neurosci 1997 17 2875-2885. 

Schoonjans K, Peinado-Onsurbe J, Le-febvre AM, Heyman RA, Briggs M, Deeb S, et al. PPARalpha and PPARgam-ma activators direct a distinct tissue-specific transcriptional response via a PPRE... 

Lau, F. and Horvath, C. 2002. Mechanisms of type I interferon cell signalling and STAT-mediated transcriptional responses. Mount Sinai Journal of Medicine 69(3), 156-168. 

George S, Gubbins M, Macintosh A, Reynolds W, Sabine V, Scott A, Thain J (2004) A comparison of pollutant biomarker responses with transcriptional responses in European flounders (Platichthys flesus) subjected to estuarine pollution. Mar Environ Res 58 571-575... 

Jolly, R. A. et al., Pooling Samples Within Microarray Studies A Comparative Analysis of Rat Liver Transcription Response to Prototypical Toxicants, Physiol. Genomics, 22, 346, 2005. 

Ma, Q. and Whitlock, J. P., A novel cytoplasmic protein that interacts with the Ah receptor, contains tetratricopeptide repeat motifs, and augments the transcriptional response to... 

The study of osteoclast differentiation is important for understanding potential new treatments for osteoporosis. Such therapies are typically explored in tissue culture models such as the Raw264 mouse monocytic cell line, which is capable of differentiation into functional multinuclear osteoclasts after treatment with the cytokine Rankl. Use of transformed cell lines raises the concern that results may not be extrapolated to normal tissue. To address this question, the transcriptional responses for Rankl treatment of the Raw264 cell line, and of two ex vivo primary cell systems (bone marrow macrophages, and hematopoetic stem cells) were compared using Affymetrix GeneChips [23]. The models proved to... 

Konu O, Kane JK, Barrett T, Vawter MP, Chang R, Ma JZ, Donovan DM, Sharp B, Becker KG, Li MD (2001) Region-specific transcriptional response to chronic nicotine in rat brain. Brain Res 909 194-203... 

Johansson T et al, Transcriptional responses of Paxillus involutus and Betula pendula during formation of ectomycorrhizal root tissue, Molec Plant Microbe Interact 17 202-215, 2004. 

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