Hormonal regulation of gene expression patterns in mosquito reproduction

Abstract Background: The red sea urchin Mesocentrotus franciscanus is an ecologically important kelp forest herbivore and an economically valuable wild fishery species. To examine of how M. franciscanus responds to its environment on a molecular level, differences in gene expression patterns were observed in embryos raised under combinations of two temperatures (13 °C and 17 °C) and two pCO2 levels (475 matm and 1050 matm). The transcriptomic responses of the embryos were assessed at two developmental stages (gastrula and prism) in light of previously described plasticity in body size and thermotolerance under these temperature and pCO2 treatments.Results: Although transcriptomic patterns primarily varied by developmental stage, there were pronounced differences in gene expression as a result of the treatment conditions. Temperature and pCO2 treatments led to the differential expression of genes related to the cellular stress response, transmembrane transport, metabolic processes, and the regulation of gene expression. Temperature had a greater influence on gene expression than pCO2, and may have contributed to positive effects of temperature on body size and thermotolerance at the prism stage. On the other hand, a relatively muted transcriptomic response to pCO2 may have permitted the stunting effect of elevated pCO2 on embryo body size.Conclusions: M. franciscanus exhibited both transcriptomic and phenotypic plasticity in response to temperature and pCO2 stress during early development. As climate change continues, red sea urchins may benefit from moderate ocean warming, whereas they will be negatively affected by ocean acidification. Present-day pCO2 conditions that occur due to coastal upwelling may already be detrimental to populations of M. franciscanus.

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The presence of two distinct prolactin receptors in seabream with different tissue distribution patterns, signal transduction pathways and regulation of gene expression by steroid hormones

Journal of Endocrinology ◽

10.1677/joe-07-0076 ◽

2007 ◽

Vol 194 (2) ◽

pp. 373-392 ◽

Cited By ~ 25

Author(s):

Xigui Huang ◽

Baowei Jiao ◽

Chun Kit Fung ◽

Yong Zhang ◽

Walter K K Ho ◽

...

Keyword(s):

Gene Expression ◽

Tissue Distribution ◽

Steroid Hormones ◽

Hormonal Regulation ◽

Promoter Activity ◽

Expression Patterns ◽

Regulation Of Gene Expression ◽

Gene Promoter ◽

Prolactin Receptors ◽

Black Seabream

Two prolactin receptors (PRLRs) encoded by two different genes were identified in the fugu and zebrafish genomes but not in the genomes of other vertebrates. Subsequently, two cDNA sequences corresponding to two PRLRs were identified in black seabream and Nile tilapia. Phylogenetic analysis of PRLR sequences in various vertebrates indicated that the coexistence of two PRLRs in a single species is a unique phenomenon in teleosts. Both PRLRs in teleosts (the classical one named as PRLR1, the newly identified one as PRLR2) resemble the long-form mammalian PRLRs. However, despite their overall structural similarities, the two PRLR subtypes in fish share very low amino acid similarities (about 30%), mainly due to differences in the intracellular domain. In particular, the Box 2 region and some intracellular tyrosine residues are missing in PRLR2. Tissue distribution study by real-time PCR in black seabream (sb) revealed that both receptors (sbPRLR1 and sbPRLR2) are widely expressed in different tissues. In gill, the expression level of sbPRLR2 is much higher than that of sbPRLR1. In the intestine, the expression of sbPRLR1 is higher than that of sbPRLR2. The expression levels of both receptors are relatively low in most other tissues, with sbPRLR1 generally higher than sbPRLR2. The sbPRLR1 and sbPRLR2 were functionally expressed in cultured human embryonic kidney 293 cells. Both receptors can activate the β-casein and c-fos promoters; however, only sbPRLR1 but not sbPRLR2 can activate the Spi promoter upon receptor stimulation in a ligand-specific manner. These results indicate that both receptors share some common functions but are distinctly different from each other in mobilizing post-receptor events. When challenged with different steroid hormones, the two PRLRs exhibited very different gene expression patterns in the seabream kidney. The sbPRLR1 expression was up-regulated by estradiol and cortisol, whereas testosterone had no significant effect. For sbPRLR2, its expression was down-regulated by estradiol and testosterone, while cortisol exerted no significant effect. The 5′-flanking regions of the sbPRLR1 and sbPRLR2 genes were cloned and the promoter activities were studied in transfected GAKS cells in the absence or presence of different steroid hormones. The results of the promoter studies were in general agreement with the in vivo hormonal regulation of gene expression results. The sbPRLR1 gene promoter activity was activated by estradiol and cortisol, but not by testosterone. In contrast, the sbPRLR2 gene promoter activity was inhibited by estradiol, cortisol, and testosterone.

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Developmental programming of DNA methylation and gene expression patterns is associated with extreme cardiovascular tolerance to anoxia in the common snapping turtle

Epigenetics & Chromatin ◽

10.1186/s13072-021-00414-7 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Ilan Ruhr ◽

Jacob Bierstedt ◽

Turk Rhen ◽

Debojyoti Das ◽

Sunil Kumar Singh ◽

...

Keyword(s):

Gene Expression ◽

Dna Methylation ◽

Binding Sites ◽

Developmental Plasticity ◽

Expression Patterns ◽

Regulation Of Gene Expression ◽

Gene Expression Patterns ◽

Anoxia Tolerance ◽

Snapping Turtle ◽

Snapping Turtles

Abstract Background Environmental fluctuation during embryonic and fetal development can permanently alter an organism’s morphology, physiology, and behaviour. This phenomenon, known as developmental plasticity, is particularly relevant to reptiles that develop in subterranean nests with variable oxygen tensions. Previous work has shown hypoxia permanently alters the cardiovascular system of snapping turtles and may improve cardiac anoxia tolerance later in life. The mechanisms driving this process are unknown but may involve epigenetic regulation of gene expression via DNA methylation. To test this hypothesis, we assessed in situ cardiac performance during 2 h of acute anoxia in juvenile turtles previously exposed to normoxia (21% oxygen) or hypoxia (10% oxygen) during embryogenesis. Next, we analysed DNA methylation and gene expression patterns in turtles from the same cohorts using whole genome bisulfite sequencing, which represents the first high-resolution investigation of DNA methylation patterns in any reptilian species. Results Genome-wide correlations between CpG and CpG island methylation and gene expression patterns in the snapping turtle were consistent with patterns observed in mammals. As hypothesized, developmental hypoxia increased juvenile turtle cardiac anoxia tolerance and programmed DNA methylation and gene expression patterns. Programmed differences in expression of genes such as SCN5A may account for differences in heart rate, while genes such as TNNT2 and TPM3 may underlie differences in calcium sensitivity and contractility of cardiomyocytes and cardiac inotropy. Finally, we identified putative transcription factor-binding sites in promoters and in differentially methylated CpG islands that suggest a model linking programming of DNA methylation during embryogenesis to differential gene expression and cardiovascular physiology later in life. Binding sites for hypoxia inducible factors (HIF1A, ARNT, and EPAS1) and key transcription factors activated by MAPK and BMP signaling (RREB1 and SMAD4) are implicated. Conclusions Our data strongly suggests that DNA methylation plays a conserved role in the regulation of gene expression in reptiles. We also show that embryonic hypoxia programs DNA methylation and gene expression patterns and that these changes are associated with enhanced cardiac anoxia tolerance later in life. Programming of cardiac anoxia tolerance has major ecological implications for snapping turtles, because these animals regularly exploit anoxic environments throughout their lifespan.

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