Gonadotropin-releasing Hormone Receptor-coupled Gene Network Organization

Abstract

An early gene cDNA microarray was developed to study genes that are regulated immediately following gonadotropin-releasing hormone (GnRH) receptor activation. 956 selected candidate genes were printed in triplicate, a t statistic-based regulation algorithm was used for data analysis, and the response to GnRH in a time course from 1 to 6 h was determined. Measurements were highly reproducible within arrays, between arrays, and between experiments. Accuracy and algorithm reliability were established by real-time polymerase chain reaction assays of 60 genes. Gene changes ranging from 1.3-to 31-fold on the microarray were confirmed by real-time polymerase chain reaction. Many of the genes were found to be highly regulated. The regulated genes identified were all elevated at 1 h of treatment and returned nearly or completely to baseline levels of expression by 3 h of treatment. This broad, robust, and transient transcriptional response to constant GnRH exposure includes modulators of signal transduction (e.g. Rgs2 and IB), cytoskeletal proteins (e.g. ␥-actin), and transcription factors (e.g. c-Fos, Egr1, and LRG21). The interplay of the activators, repressors, and feedback inhibitors identified embodies a combinatorial code to direct the activity of specific downstream secondary genes.

Comprehensive expression analysis of a rat depression model

“…These results showed the same direction of expressional changes seen in the microarray experiments, but less correlation was found with the degree of change between the two methods, as indicated in prior studies. 25,26 Furthermore, since only a limited number of transcripts were confirmed by independent methods and no transcripts were confirmed when Bonferroni's correction was applied to the quantitative RT-PCR results, the present DNA microarray data are broadly unconfirmed.…”

Expression Profiling Identifies Genes That Continue to Respond to Insulin in Adipocytes Made Insulin-resistant by Treatment with Tumor Necrosis Factor-α

“…Egr-1 and Fra-1), the FC in response to insulin treatment was lower using the GeneChips® compared with real-time RT-PCR. This behavior is, however, not unusual and has been previously observed, especially for transcripts that are highly regulated (28,29). Among the 12 genes (including MCP-1) tested and validated using real-time RT-PCR, PAI-1 was the only gene that was classified differently by RT-PCR analysis (i.e.…”

Early Single Cell Bifurcation of Pro- and Antiapoptotic States during Oxidative Stress

“…Preparation of cRNA, hybridization, and scanning of the rat genome U34 arrays were performed as described previously (34,35). Affymetrix microarray suite 5.0 was used to analyze the raw data using the criteria of 60% concordance across multiple array comparisons and -fold changes Ն1.6 for outlier detection.…”