Conservation of estrogen receptor function in invertebrate reproduction

Abstract

BackgroundRotifers are microscopic aquatic invertebrates that reproduce both sexually and asexually. Though rotifers are phylogenetically distant from humans, and have specialized reproductive physiology, this work identifies a surprising conservation in the control of reproduction between humans and rotifers through the estrogen receptor. Until recently, steroid signaling has been observed in only a few invertebrate taxa and its role in regulating invertebrate reproduction has not been clearly demonstrated. Insights into the evolution of sex signaling pathways can be gained by clarifying how receptors function in invertebrate reproduction.ResultsIn this paper, we show that a ligand-activated estrogen-like receptor in rotifers binds human estradiol and regulates reproductive output in females. In other invertebrates characterized thus far, ER ligand binding domains have occluded ligand-binding sites and the ERs are not ligand activated. We have used a suite of computational, biochemical and biological techniques to determine that the rotifer ER binding site is not occluded and can bind human estradiol.ConclusionsOur results demonstrate that this mammalian hormone receptor plays a key role in reproduction of the ancient microinvertebrate Brachinous manjavacas. The presence and activity of the ER within the phylum Rotifera indicates that the ER structure and function is highly conserved throughout animal evolution.Electronic supplementary materialThe online version of this article (doi:10.1186/s12862-017-0909-z) contains supplementary material, which is available to authorized users.

Genomic signatures of local adaptation to the degree of environmental predictability in rotifers

“…Indeed, a gene associated to hatching fraction is described as “coronin-7 isoform X1” and is involved in the actin filament polymerization, which is upregulated in diapausing mosquitos 60 . A gene associated to hydroperiod, described as “estrogen receptor beta”, which increases reproduction when being activated by a ligand in the rotifer Brachionus manjavacas 61 . Moreover, a gene associated to predictability is described as “POU class transcription factor 1-like”, a transcription factor which is more expressed in non-diapause than in diapause pupae in the moth Helicoverpa armigera 62 .…”

Homology models of mouse and rat estrogen receptor-α ligand-binding domain created by in silico mutagenesis of a human template: Molecular docking with 17β-estradiol, diethylstilbestrol, and paraben analogs

“…Indeed, in recent years, homology models in general have gained wide acceptance as a means of producing high-quality protein structures for research investigations and as docking targets [74, 81, 82]. With respect to estrogen receptors, homology models of ER receptors based on X-ray crystal structures of human ERα have been created for human (ERβ) [83], lizard (3 species) [84], medaka (3 varieties) [85], rainbow trout [86], rotifer [87], and zebrafish [88]. These estrogen receptor homology models have been used in evolutionary and physiological research and as docking targets with applications in ecological toxicology.…”

“…The best overall results were obtained with the simplest procedure: in silico mutagenesis and energy minimization with YASARA-Structure. This technique could be employed in future studies to gain insight into species differences in ligand binding [76], evolutionary or physiological investigations [84, 87, 88], studies of ERα-LBD mutations in breast cancer or other diseases [68–70, 89, 90, 92], ecological toxicology [85, 86, 124], and genetic engineering of mutant ERα-LBDs for use in bio-detection of ligands in assays or biosensors [93]. …”

Fluorescence imaging using synthetic GFP chromophores

“…An activation and localization of NRs in the presence of GFP Cros was performed in cells ( Figure 4c) and in large microorganisms ( Figure 4d). 67…”