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Genes that regulate hormone release are essential for maintaining metabolism and energy balance. Egr1 encodes a transcription factor that regulates hormone production and release, and a decreased in growth hormones has been reported in Egr1 knockout mice. A reduction in growth hormones has also been observed in Nestin-Cre mice, a model frequently used to study the nervous system. Currently, it is unknown how Egr1 loss or the Nestin-Cre driver disrupt pituitary gene expression. Here, we compared the growth curves and pituitary gene expression profiles of Nestin-Cre-mediated Egr1 conditional knockout (Egr1cKO) mice with those of their controls. Reduced body weight was observed in both the Nestin-Cre and Egr1cKO mice, and the loss of Egr1 had a slightly more severe impact on female mice than on male mice. RNA-seq data analyses revealed that the sex-related differences were amplified in the Nestin-Cre-mediated Egr1 conditional knockout mice. Additionally, in the male mice, the influence of Egr1cKO on pituitary gene expression may be overridden by the Nestin-Cre driver. Differentially expressed genes associated with the Nestin-Cre driver were significantly enriched for genes related to growth factor activity and binding. Altogether, our results demonstrate that Nestin-Cre and the loss of Egr1 in the neuronal cell lineage have distinct impacts on pituitary gene expression in a sex-specific manner.
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Prediction and experimental validation of a new salinity-responsive cis-regulatory element (CRE) in tilapia
Quantitative DIA proteomics in combination with the transcription inhibitor actinomycin D was performed on the tilapia OmB cell line to identify proteins that are upregulated by transcriptional regulation during hyperosmotic stress. This analysis revealed proteins that are transcriptionally up-regulated by hyperosmolality in these cells. The promoter regions of these proteins were compared and a novel hyperosmolality-induced cis-regulatory element (CRE) and corresponding transcription factor candidate were identified. The CRE was experimentlly validated by site-directed mutagenesis in combination with reporter assays.
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- Award ID(s):
- 2209383
- PAR ID:
- 10608754
- Publisher / Repository:
- Panorama Public
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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