EGR1/2 ELISA Kit

Background: Exposure to adverse environmental conditions such as toxic chemicals, viral infections, and even stress during pregnancy or early life may disrupt the development of normal brain and its functioning leading to incidence of neurodevelopmental disorders at later stages of life. Recently, we reported that poly (I:C) exposure altered synaptic plasticity protein level and impaired memory through activation of microglia cells. Purpose: As epigenetic modifications are involved in memory formation, we have studied methylation of DNA and acetylation of histone at promoters of synaptic plasticity genes in the brain of rats exposed to poly (I:C) during early life. Methods: One dose of poly (I:C) (5 mg/kg bw) was intraperitoneally injected to rat pups on postnatal seventh day. A set of pups exposed to vehicle was included as control. In order to assess methylation of DNA and acetylation of histone at synaptic plasticity gene promoter, we performed qPCR after methylated DNA immunoprecipitation and chromatin immunoprecipitation. Results: Poly (I:C) exposure reduced the level of 5-methylcytosine (5mC) at synaptic plasticity gene (bdnf, arc, and egr1) promoters in the frontal cortex (FC) and hippocampus of 3-week rats, although increased it later in both regions of 12-week rats as compared to respective controls. On contrary, poly (I:C) exposure enhanced acetylation of histone H3K9 (H3K9Ac) at promoters of these genes in both regions of 3-week rats but decreased in 12-week rats. Conclusion: Poly (I:C) exposure altered 5mC and H3K9Ac at synaptic plasticity gene promoters resulting in memory impairment of rats at later life.

L beta T2 and alpha T3-1 are important, widely studied cell line models for the pituitary gonadotropes that were generated by targeted tumorigenesis in transgenic mice. L beta T2 cells are more mature gonadotrope precursors than alpha T3-1 cells. Microsatellite authentication patterns, chromosomal characteristics, and their intercellular variation have not been reported. We performed microsatellite and cytogenetic analysis of both cell types at early passage numbers. Short tandem repeat (STR) profiling was consistent with a mixed C57BL/6J x BALB/cJ genetic background, with distinct patterns for each cell type. Spectral karyotyping in alpha T3-1 cells revealed cell-to-cell variation in chromosome composition and pseudodiploidy. In L beta T2 cells, chromosome counting and karyotyping demonstrated pseudotriploidy and high chromosomal variation among cells. Chromosome copy number variation was confirmed by single-cell DNA sequencing. Chromosomal compositions were consistent with a male sex for alpha T3-1 and a female sex for L beta T2 cells. Among L beta T2 stocks used in multiple laboratories, we detected two genetically similar but distinguishable lines via STR authentication, L beta T2a and L beta T2b. The two lines differed in morphological appearance, with L beta T2a having significantly smaller cell and nucleus areas. Analysis of immediate early gene and gonadotropin subunit gene expression revealed variations in basal expression and responses to continuous and pulsatile GnRH stimulation. L beta T2a showed higher basal levels of Egr1, Fos, and Lhb but lower Fos induction. Fshb induction reached significance only in L beta T2b cells. Our study highlights the heterogeneity in gonadotrope cell line genomes and provides reference STR authentication patterns that can be monitored to improve experimental reproducibility and facilitate comparisons of results within and across laboratories. Copyright (C) 2019 Endocrine Society