Somatostatin Is Essential for the Sexual Dimorphism of GH Secretion, Corticosteroid-Binding Globulin Production, and Corticosterone Levels in Mice

Abstract Distinct male and female patterns of pituitary GH secretion produce sexually differentiated hepatic gene expression profiles, thereby influencing steroid and xenobiotic metabolism. We used a fully automated system to obtain serial nocturnal blood samples every 15 minutes from cannulated wild-type (WT) and somatostatin knockout (Sst-KO) mice to determine the role of SST, the principal inhibitor of GH release, in the generation of sexually dimorphic GH pulsatility. WT males had lower mean and median GH values, less random GH secretory bursts, and longer trough periods between GH pulses than WT females. Each of these parameters was feminized in male Sst-KO mice, whereas female Sst-KO mice had higher GH levels than all other groups, but GH pulsatility was unaffected. We next performed hepatic mRNA profiling with high-density microarrays. Male Sst-KO mice exhibited a globally feminized pattern of GH-dependent mRNA levels, but female Sst-KO mice were largely unaffected. Among the differentially expressed female-predominant genes was Serpina6, which encodes corticosteroid-binding globulin (CBG). Increased CBG was associated with elevated diurnal peak plasma corticosterone in unstressed WT females and both sexes of Sst-KO mice compared with WT males. Sst-KO mice also had exaggerated ACTH and corticosterone responses to acute restraint stress. However, consistent with their lack of phenotypic signs of excess glucocorticoids, cerebrospinal fluid concentrations of free corticosterone in Sst-KO mice were not elevated. In summary, SST is necessary for the prolonged interpulse troughs that define masculinized pituitary GH secretion. SST also contributes to sexual dimorphism of the hypothalamic-pituitary-adrenal axis via GH-dependent regulation of hepatic CBG production.

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X chromosome escapee genes are involved in ischemic sexual dimorphism through epigenetic modification of inflammatory signals

Journal of Neuroinflammation ◽

10.1186/s12974-021-02120-3 ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Shaohua Qi ◽

Abdullah Al Mamun ◽

Conelius Ngwa ◽

Sharmeen Romana ◽

Rodney Ritzel ◽

...

Keyword(s):

Sexual Dimorphism ◽

X Chromosome ◽

Epigenetic Modification ◽

Artery Occlusion ◽

Sexually Dimorphic ◽

Mrna Levels ◽

Young Females ◽

Human Stroke ◽

Histone H3k4 ◽

Cerebral Artery Occlusion

Abstract Background Stroke is a sexually dimorphic disease. Previous studies have found that young females are protected against ischemia compared to males, partially due to the protective effect of ovarian hormones, particularly estrogen (E2). However, there are also genetic and epigenetic effects of X chromosome dosage that contribute to stroke sensitivity and neuroinflammation after injury, especially in the aged. Genes that escape from X chromosome inactivation (XCI) contribute to sex-specific phenotypes in many disorders. Kdm5c and kdm6a are X escapee genes that demethylate H3K4me3 and H3K27me3, respectively. We hypothesized that the two demethylases play critical roles in mediating the stroke sensitivity. Methods To identify the X escapee genes involved in stroke, we performed RNA-seq in flow-sorted microglia from aged male and female wild type (WT) mice subjected to middle cerebral artery occlusion (MCAO). The expression of these genes (kdm5c/kdm6a) were confirmed in four core genotypes (FCG) mice and in post-mortem human stroke brains by immunohistochemistry (IHC), Western blot, and RT-PCR. Chromatin immunoprecipitation (ChIP) assays were conducted to detect DNA levels of inflammatory interferon regulatory factor (IRF) 4/5 precipitated by histone H3K4 and H3K27 antibodies. Manipulation of kdm5c/kdm6a expression with siRNA or lentivirus was performed in microglial culture, to determine downstream pathways and examine the regulatory roles in inflammatory cytokine production. Results Kdm5c and kdm6a mRNA levels were significantly higher in aged WT female vs. male microglia, and the sex difference also existed in ischemic brains from FCG mice and human stroke patients. The ChIP assay showed the IRF 4/5 had higher binding levels to demethylated H3K4 or H3K27, respectively, in female vs. male ischemic microglia. Knockdown or over expression of kdm5c/kdm6a with siRNA or lentivirus altered the methylation of H3K4 or H3K27 at the IRF4/5 genes, which in turn, impacted the production of inflammatory cytokines. Conclusions The KDM-Histone-IRF pathways are suggested to mediate sex differences in cerebral ischemia. Epigenetic modification of stroke-related genes constitutes an important mechanism underlying the ischemic sexual dimorphism.

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Integrative Genomics with Mediation Analysis in a Survival Context

Computational and Mathematical Methods in Medicine ◽

10.1155/2013/413783 ◽

2013 ◽

Vol 2013 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Szilárd Nemes ◽

Toshima Z. Parris ◽

Anna Danielsson ◽

Zakaria Einbeigi ◽

Gunnar Steineck ◽

...

Keyword(s):

Expression Profiles ◽

Gene Expression Profiles ◽

Genomic Analysis ◽

Mrna Levels ◽

Integrative Genomics ◽

Asymptotic Results ◽

Data Set ◽

Cancer Data ◽

Dna And Rna ◽

Altered Gene

DNA copy number aberrations (DCNA) and subsequent altered gene expression profiles may have a major impact on tumor initiation, on development, and eventually on recurrence and cancer-specific mortality. However, most methods employed in integrative genomic analysis of the two biological levels, DNA and RNA, do not consider survival time. In the present note, we propose the adoption of a survival analysis-based framework for the integrative analysis of DCNA and mRNA levels to reveal their implication on patient clinical outcome with the prerequisite that the effect of DCNA on survival is mediated by mRNA levels. The specific aim of the paper is to offer a feasible framework to test the DCNA-mRNA-survival pathway. We provide statistical inference algorithms for mediation based on asymptotic results. Furthermore, we illustrate the applicability of the method in an integrative genomic analysis setting by using a breast cancer data set consisting of 141 invasive breast tumors. In addition, we provide implementation in R.

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Analysis of ceRNA networks and identification of potential drug targets for drug-resistant leukemia cell K562/ADR

PeerJ ◽

10.7717/peerj.11429 ◽

2021 ◽

Vol 9 ◽

pp. e11429

Author(s):

Zhaoping Liu ◽

Yanyan Wang ◽

Zhenru Xu ◽

Shunling Yuan ◽

Yanglin Ou ◽

...

Keyword(s):

Drug Resistance ◽

Drug Targets ◽

Regulatory Networks ◽

Expression Profiles ◽

Leukemia Cell ◽

Gene Expression Profiles ◽

Leukemia Cells ◽

Mrna Levels ◽

Drug Resistant ◽

Cerna Network

Background Drug resistance is the main obstacle in the treatment of leukemia. As a member of the competitive endogenous RNA (ceRNA) mechanism, underlying roles of lncRNA are rarely reported in drug-resistant leukemia cells. Methods The gene expression profiles of lncRNAs and mRNAs in doxorubicin-resistant K562/ADR and sensitive K562 cells were established by RNA sequencing (RNA-seq). Expression of differentially expressed lncRNAs (DElncRNAs) and DEmRNAs was validated by qRT-PCR. The potential biological functions of DElncRNAs targets were identified by GO and KEGG pathway enrichment analyses, and the lncRNA-miRNA-mRNA ceRNA network was further constructed. K562/ADR cells were transfected with CCDC26 and LINC01515 siRNAs to detect the mRNA levels of GLRX5 and DICER1, respectively. The cell survival rate after transfection was detected by CCK-8 assay. Results The ceRNA network was composed of 409 lncRNA-miRNA pairs and 306 miRNA-mRNA pairs based on 67 DElncRNAs, 58 DEmiRNAs and 192 DEmRNAs. Knockdown of CCDC26 and LINC01515 increased the sensitivity of K562/ADR cells to doxorubicin and significantly reduced the half-maximal inhibitory concentration (IC50) of doxorubicin. Furthermore, knockdown of GLRX5 and DICER1 increased the sensitivity of K562/ADR cells to doxorubicin and significantly reduced the IC50 of doxorubicin. Conclusions The ceRNA regulatory networks may play important roles in drug resistance of leukemia cells. CCDC26/miR-140-5p/GLRX5 and LINC01515/miR-425-5p/DICER1 may be potential targets for drug resistance in K562/ADR cells. This study provides a promising strategy to overcome drug resistance and deepens the understanding of the ceRNA regulatory mechanism related to drug resistance in CML cells.

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NITUMID: Nonnegative matrix factorization-based Immune-TUmor MIcroenvironment Deconvolution

Bioinformatics ◽

10.1093/bioinformatics/btz748 ◽

2019 ◽

Author(s):

Daiwei Tang ◽

Seyoung Park ◽

Hongyu Zhao

Keyword(s):

Tumor Microenvironment ◽

Matrix Factorization ◽

Nonnegative Matrix Factorization ◽

Expression Profiles ◽

Mrna Level ◽

Nonnegative Matrix ◽

Gene Expression Profiles ◽

Cell Types ◽

Supplementary Information ◽

Mrna Levels

Abstract Motivation A number of computational methods have been proposed recently to profile tumor microenvironment (TME) from bulk RNA data, and they have proved useful for understanding microenvironment differences among therapeutic response groups. However, these methods are not able to account for tumor proportion nor variable mRNA levels across cell types. Results In this article, we propose a Nonnegative Matrix Factorization-based Immune-TUmor MIcroenvironment Deconvolution (NITUMID) framework for TME profiling that addresses these limitations. It is designed to provide robust estimates of tumor and immune cells proportions simultaneously, while accommodating mRNA level differences across cell types. Through comprehensive simulations and real data analyses, we demonstrate that NITUMID not only can accurately estimate tumor fractions and cell types’ mRNA levels, which are currently unavailable in other methods; it also outperforms most existing deconvolution methods in regular cell type profiling accuracy. Moreover, we show that NITUMID can more effectively detect clinical and prognostic signals from gene expression profiles in tumor than other methods. Availability and implementation The algorithm is implemented in R. The source code can be downloaded at https://github.com/tdw1221/NITUMID. Supplementary information Supplementary data are available at Bioinformatics online.

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Gene Expression Profiles Involved in γ to β Globin Gene Switching during Erythroid Maturation.

Blood ◽

10.1182/blood.v106.11.820.820 ◽

2005 ◽

Vol 106 (11) ◽

pp. 820-820

Author(s):

Wei Li ◽

Betty S. Pace

Keyword(s):

Gene Expression ◽

Expression Profiles ◽

Globin Gene ◽

Gene Expression Profiles ◽

Phase System ◽

Mrna Levels ◽

Erythroid Progenitors ◽

Globin Mrna ◽

Gene Switching ◽

Globin Gene Expression

Abstract The design and evaluation of therapies for sickle cell disease (SCD) rely on our understanding of hemoglobin accumulation during erythropoiesis and sequential globin gene expression (ε → Gγ → Aγ → δ → β) during development. To gain insights into globin gene switching, we completed time course micorarray analyses of erythroid progenitors to identify trans-factors involved in γ gene activation. Studies were completed to map the pattern of γ and β globin gene expression in progenitors grown from normal peripheral blood mononuclear cells. We compared cells grown in a 2-phase (phase 1, d0-6: SCF, IL-3, IL-6, and GM-CSF and phase 2, d7-25: SCF and EPO) vs. 1-phase (d0-34: SCF, IL-3, and EPO) liquid culture system. From day 0 to 34 in either system cell viability remained >99%. Total RNA was isolated using Trizol and column cleanup (Qiagen). Globin mRNA levels were measured at 2–3 day intervals by quantitative PCR (qPCR). In the 2-phase system γ-globin mRNA>β-globin mRNA up to d14, 4 days of approximately equal expression then β mRNA > γ mRNA by d20. By contrast, in 1-phase studies there was a rapid switch around d20(see graph). We speculate that this difference may be due to the early addition of EPO on d0 therefore we continued our detailed analysis in this system. To confirm that our in vitro system recapitulates in vivo gene expression patterns, we completed studies to ascertain Gγ - vs. Aγ globin mRNA levels. The normalized Gγ:Aγ ratio decreased from ~3:1 on d7 to ~1:1 by d34; These findings were confirmed using two sets of Gγ and Aγ globin primers. We concluded that the 1-phase system recapitulated normal γ/β globin switching and that gene profiling studies to identify the trans-factor involved in switching mechanisms were feasible. We used Discover oligo chips (ArrayIt, Sunnyvale, CA) containing 380 human genes selected from 30 major functional groups including hematopoiesis. To aide interpretation of chip data, cell populations were rated morphologically using Giemsa stained cytospin preps. From d16 on we observed an increase in late erythroid progenitors (normoblasts) from 1% to 71% by d31. After verifying RNA quality by gel inspection of ribosomal molecules, we prepared Cy3 and Cy5 probes for early and late time-point RNA samples respectively. Chip analysis was performed at several time points but d0/21, d7/21, and d21/28 were most informative. Based on Axon GenePixPro 6.0 and Acuity 4.0 software analysis we found the following genes with >1.5-fold change in expression profile (shown as down-regulated/up-regulated genes): d0/21: 33/73, d7/21: 13/25, and d21/28:35/26. Principal component analysis (PCA), hierarchical clusters and self organizing maps were constructed. Gene profiles were correlated with the γ/β switching curve using d7 (γ >β), d21 (γ ~ β), and d28 (γ <β) data. Hematopoietic dataset analysis at d21 revealed 4 candidate γ-globin gene activators including v-myb, upsteam binding transfactor -RNApol1 and 2 zinc finger proteins. Analysis of a d28 dataset revealed 12 proteins involved in γ-globin gene silencing including IL-3, SCF, MAPKKK3, v-raf-1, ATF-2, and glucocorticoid receptor DNA binding factor 1 among others. Gene expression profiles will be validated using qPCR and promising candidates will be tested by forced expression in transient and stable reporter systems. Figure Figure

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Gene expression profiles in HEK-293 cells with low or high store-operated calcium entry: can regulatory as well as regulated genes be identified?

Physiological Genomics ◽

10.1152/physiolgenomics.00099.2004 ◽

2005 ◽

Vol 21 (1) ◽

pp. 14-33 ◽

Cited By ~ 19

Author(s):

Tatiana K. Zagranichnaya ◽

Xiaoyan Wu ◽

Arpad M. Danos ◽

Mitchel L. Villereal

Keyword(s):

Gene Expression ◽

Transient Receptor Potential ◽

Expression Profiles ◽

Physiological Role ◽

Gene Expression Profiles ◽

Pcr Analysis ◽

Mrna Levels ◽

Hek 293 ◽

Hek 293 Cells ◽

293 Cells

Gene expression profiles were generated using cDNA microarray technology for clones of human embryonic kidney (HEK)-293 cells selected to have either high or low levels of store-operated Ca2+ entry (SOCE). For five high clones, three low clones, and control HEK-293 cells, duplicate Affymetrix U133A human gene arrays were run after extraction of total RNA from cells growing in the presence of serum. Of the ∼22,000 genes represented on the microarray, 58 genes had readings at least twofold higher, while 32 genes had readings at least twofold lower, in all five high SOCE clones compared with control HEK-293 cells. In the low SOCE clones, 92 genes had readings at least twofold higher, while 58 genes had readings at least twofold lower, than in HEK-293 cells. Microarray results were confirmed for 18 selected genes by real-time RT-PCR analysis; for six of those genes, predicted changes in the low SOCE clone were confirmed by an alternative method, monitoring mRNA levels in HEK-293 with SOCE decreased by expression of small interfering (si)RNA to canonical transient receptor potential protein-1. Genes regulated by SOCE are involved in signal transduction, transcription, apoptosis, metabolism, and membrane transport. These data provide insight into the physiological role of SOCE. In addition, a potential regulator of SOCE, insulin receptor substrate (IRS)-2, has been identified. A reduction of IRS-2 levels by siRNA methods in two high clones dramatically reduced SOCE, whereas overexpression of IRS-2 in a low SOCE clone elevated SOCE.

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Impaired Innate Immunity Mechanisms in the Brain of Alzheimer’s Disease

International Journal of Molecular Sciences ◽

10.3390/ijms21031126 ◽

2020 ◽

Vol 21 (3) ◽

pp. 1126 ◽

Cited By ~ 2

Author(s):

Martina Romagnoli ◽

Elisa Porcellini ◽

Ilaria Carbone ◽

Robert Veerhuis ◽

Federico Licastro

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Expression Profiles ◽

Temporal Cortex ◽

Gene Expression Profiles ◽

Mrna Levels ◽

Virus Infections ◽

Apoe Ε4 ◽

Age Related ◽

Persistent Virus

Among environmental factors likely associated with Alzheimer’s disease (AD), persistent virus infections, and age-related progressive decline of immune competence might play a pivotal role. However, AD antimicrobial brain immune responses are poorly investigated. The present study focused on genes involved in antimicrobial defenses, especially against virus infections, in the AD brain. In particular, mRNA levels of IRF7, MED23, IL28B, and IFN-α genes were analyzed in hippocampus and temporal cortex brain samples from AD and non-demented controls. All subjects were also genotyped for APOE ε, IRF7, MED23, and IL28B gene polymorphisms. Most AD patients showed decreased mRNA levels of all investigated genes in the hippocampus and temporal cortex. However, a small group of AD patients showed increased hippocampal mRNA expression of MED23, IL28B, and IFN-α. mRNA levels of MED23, IL28B, IFN-α from the hippocampus and those of MED23 from the temporal cortex were further decreased in APOE ε4 allele AD carriers. Moreover, rs6598008 polymorphism of IRF7 was significantly associated with decreased hippocampal expression of IRF7, MED23, IL28B, and IFN-α. These findings suggest that AD brains show impaired innate antimicrobial gene expression profiles, and individual genetic makeup, such as positivity for the APOE ε4 and IRF7 A alleles, might affect brain immune efficiency.

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Sexual dimorphism of hepatic 11β-hydroxysteroid dehydrogenase in the rat: the role of growth hormone patterns

Journal of Endocrinology ◽

10.1677/joe.0.1430541 ◽

1994 ◽

Vol 143 (3) ◽

pp. 541-548 ◽

Cited By ~ 77

Author(s):

S C Low ◽

K E Chapman ◽

C R W Edwards ◽

T Wells ◽

I C A F Robinson ◽

...

Keyword(s):

Gene Expression ◽

Sexual Dimorphism ◽

Mrna Expression ◽

Hydroxysteroid Dehydrogenase ◽

Male Rats ◽

Total Daily Dose ◽

Mrna Levels ◽

Control Female ◽

Gh Secretion ◽

Repressive Effect

Abstract 11 β-Hydroxysteroid dehydrogenase (11β-HSD) catalyses the reversible metabolism of corticosterone to inert 11-dehydrocorticosterone. At least two isoforms exist. 11β-HSD-1, the first to be characterised and the only isoform for which a cDNA has been isolated, is highly expressed in liver, kidney and hippocampus. The activity of 11β-HSD in rat liver is higher in males, due to oestrogen repression of 11β-HSD-1 gene transcription in females. Sexual dimorphism in rodent liver proteins is frequently mediated indirectly via sex-specific patterns of GH release (continuous in females, pulsatile in males). We have now investigated whether this applies to 11β-HSD, using dwarf rats (congenitally deficient in GH) and hypophysectomised animals. 11β-HSD activity and 11β-HSD-1 mRNA expression in liver was significantly lower in control female than male rats (50% and 72% of male levels respectively). These sex differences in the liver were attenuated in dwarf rats, with both males and females showing similar levels of 11 β-HSD activity to control males. Administration of continuous (female pattern) GH to dwarf male rats decreased hepatic 11β-HSD activity (30% fall) and mRNA expression (77% fall), whereas the same total daily dose of GH given in the male (pulsatile) pattern had no effect on hepatic 11 β-HSD in female dwarf rats. Continuous GH also attenuated hepatic 11 β-HSD activity (25% fall) and 11β-HSD-1 mRNA expression (82% fall) in hypophysectomised animals. However, oestradiol itself suppressed hepatic 11β-HSD activity (25% fall) and 11β-HSD-1 mRNA expression (60% fall) in hypophysectomised rats. Renal 11 β-HSD activity showed no sexual dimorphism in control or dwarf rats, although overall activity was lower in dwarf animals. By contrast, 11β-HSD-1 mRNA expression was higher in male than female kidney in both control and dwarf strains. Neither GH pattern had any effect on 11β-HSD activity or 11β-HSD-1 mRNA levels in the kidney of dwarf rats, although continuous GH attenuated 11β-HSD activity (28% fall) and 11β-HSD-1 mRNA expression in kidney (47% decrease) in hypophysectomised animals. Oestradiol attenuated renal 11β-HSD-1 mRNA expression (74% fall) in hypophysectomised rats, but increased enzyme activity (62% rise) in the kidney. None of the manipulations had any effect on hippocampal 11 β-HSD activity or gene expression. These data demonstrate the following. (i) Sexual dimorphism of hepatic 11β-HSD is mediated, in part, via sex-specific patterns of GH secretion acting on 11β-HSD-1 gene expression. (ii) There is an additional direct repressive effect of oestrogen on hepatic 11β-HSD-1. (iii) Other tissue-specific factors are involved in regulating 11β-HSD-1, as neither peripheral GH nor oestrogen have effects upon hippocampal 11β-HSD-1. (iv) The regulation of 11β-HSD-1 mRNA expression in the kidney broadly parallels the liver. The lack of correlation between changes in expression of the 11β-HSD-1 gene and renal 11β-HSD activity reflects the presence of an additional gene product(s) in the kidney, the expression of which is largely independent of GH. Journal of Endocrinology (1994) 143, 541–548

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AEBP1 Is One of the Epithelial-Mesenchymal Transition Regulatory Genes in Colon Adenocarcinoma

BioMed Research International ◽

10.1155/2021/3108933 ◽

2021 ◽

Vol 2021 ◽

pp. 1-16

Author(s):

Dandan Li ◽

Zhi Liu ◽

Xiaorong Ding ◽

Zhensheng Qin

Keyword(s):

Cancer Metastasis ◽

Epithelial Mesenchymal Transition ◽

Expression Profiles ◽

Gene Expression Profiles ◽

Colon Adenocarcinoma ◽

The Cancer Genome Atlas ◽

Mrna Levels ◽

Mesenchymal Transition ◽

Tumor Cell Migration ◽

Promising Target

Epithelial-mesenchymal transition (EMT) is involved in various tumor processes, including tumorigenesis, tumor cell migration and metastasis, tumor stemness, and therapeutic resistance. Therefore, it is important to identify the genes most associated with EMT and develop them as therapeutic targets. In this work, we first analyzed EMT hallmark gene expression profiles among 10,535 pan-cancer samples from The Cancer Genome Atlas (TCGA) and divided them into EMT high and EMT low groups according to the metagene scores. Then, we identified 12 genes that were most associated with high EMT metagene score ( R > 0.9 ) in 329 colon adenocarcinoma (COAD) patients. Among them, only 4 genes (AEBP1, KCNE4, GFPT2, and FAM26E) had statistically significant differences in prognosis ( P < 0.05 ). Next, we selected AEBP1 as a candidate and showed that AEBP1 mRNA levels and EMT biomarkers strongly coexpressed in 329 COAD samples. In addition, AEBP1 was highly expressed and associated with poor clinical outcomes and prognosis in COAD patients. Finally, to explore whether AEBP1-mediated EMT was related to the tumor microenvironment (TME), we examined AEBP1 expression levels at the single-cell levels. Our results showed that AEBP1 levels were extremely high in tumor-associated fibroblasts, which may induce EMT. AEBP1 expression was also positively correlated with the expression of fibroblast biomarkers and also with EMT metascores, suggesting that AEBP1-mediated EMT may be associated with the stimulation of fibroblast activation. Therefore, AEBP1 may be a promising target for EMT inhibition, which reduces cancer metastasis and drug resistance in COAD patients.

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SAT-441 Transcriptome Analysis Under Differential Thyroid Hormone Treatment During Mouse Cerebellar Development

Journal of the Endocrine Society ◽

10.1210/jendso/bvaa046.1003 ◽

2020 ◽

Vol 4 (Supplement_1) ◽

Author(s):

Hiroyuki Yajima ◽

Ishii Sumiyasu ◽

Wataru Miyazaki ◽

Noriyuki Koibuchi

Keyword(s):

Gene Expression ◽

Transcriptional Regulation ◽

Thyroid Hormone ◽

Target Genes ◽

Expression Profiles ◽

Gene Expression Profiles ◽

Hormone Treatment ◽

Cerebellar Development ◽

Mrna Levels ◽

Dependent Manner

Abstract Background: Thyroid hormone (TH) plays essential roles in the development of the cerebellum by regulating transcription of target genes. TH binds to TH receptor (TR) located in the cell nucleus and stimulates transcription through TH response element (TRE). The expression of many genes is temporary and spatially regulated by TH during cerebellar development. However, the mode of transcription by TR may vary among target genes. In the liver, different duration of TH exposure resulted in distinct gene expression profiles. To examine the mechanisms of transcriptional regulation by TH in cerebellar development, gene expression profile induced by various TH exposure duration was studied. Methods: Anti-thyroid drug propylthiouracil (250 ppm in drinking water) was administered to C57BL/6J mice from the gestational day 14 to postnatal day (P) 7 to generate perinatal hypothyroid mice. To study the effect of continuous TH exposure, TH was subcutaneously administered to hypothyroid pups from P2 to P7 (6 days group). To study the effect of single TH administration, TH was injected on P7 and mice were sacrificed either 6 (6 hours group) or 24 hours (24 hours group) after injection. Cerebellar samples were collected to extract RNA and subject to microarray analysis. Microarray results were confirmed by RT-qPCR. Results: In microarray result, compared with mRNA levels of hypothyroid mice, 6 days group induced upregulation in 1007 genes and downregulation in 1009 genes, 6 hours group induced upregulation in 355 genes and downregulation in 977 genes, and 24 hours group induced upregulation in 365 genes and downregulation in 1121 genes. Only 7.6% of the genes were overlapped in three groups among positively regulated genes. In contrast, 57.2% of the genes were common in the negatively regulated genes. In RT-qPCR result, among genes known to harbor TRE, Hairless, Pcp2, and Nrgn, showed differential upregulation patterns. Hairless was upregulated in all groups, whereas Pcp2 was upregulated only in 5 days group and Nrgn was not upregulated in all groups. These results suggest that different mode of transcriptional regulation occurred in an exposure time-dependent manner of TH. Conclusion: We identified gene groups whose expression were modified by TH during cerebellar development. TH distinctively regulates transcription of target genes depending on the exposure schedule in mouse developing cerebellum.

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