Phosphorylation of human placental aromataseCYP19A1

Abstract

Aromatase CYP19A1 catalyzes the synthesis of estrogens in endocrine, reproductive and central nervous systems. Higher levels of 17β-estradiol (E2) are associated with malignancies and diseases of the breast, ovary and endometrium, while low E2 levels increase the risk for osteoporosis, cardiovascular diseases and cognitive disorders. E2, the transcriptional activator of the estrogen receptors, is also known to be involved in non-genomic signaling as a neurotransmitter/neuromodulator, with recent evidence for rapid estrogen synthesis (RES) within the synaptic terminal. Although regulation of brain aromatase activity by phosphorylation/dephosphorylation has been suggested, it remains obscure in the endocrine and reproductive systems. RES and overabundance of estrogens could stimulate the genomic and non-genomic signaling pathways, and genotoxic effects of estrogen metabolites. Here, by utilizing biochemical, cellular, mass spectrometric, and structural data we unequivocally demonstrate phosphorylation of human placental aromatase and regulation of its activity. We report that human aromatase has multiple phosphorylation sites, some of which are consistently detectable. Phosphorylation of the residue Y361 at the reductase-coupling interface significantly elevates aromatase activity. Other sites include the active site residue S478 and several at the membrane interface. We present the evidence that two histidine residues are phosphorylated. Furthermore, oxidation of two proline residues near the active site may have implications in regulation. Taken together, the results demonstrate that aromatase activity is regulated by phosphorylation and possibly other post-translational modifications. Protein level regulation of aromatase activity not only represents a paradigm shift in estrogen-mediated biology, it could also explain unresolved clinical questions such as aromatase inhibitor resistance.

A Hetero-Multimeric Chitinase-Containing Plasmodium falciparum and Plasmodium gallinaceum Ookinete-Secreted Protein Complex Involved in Mosquito Midgut Invasion

“…A final wash with 50% CH 3 CN/10 mM NH 4 HCO 3 was given and gel pieces were completely dried prior to removal of the wash solution. Trypsin digestion was carried out by incubating the sample at 37°C for 18 h and the samples were stored at -20°C until analysis ( Ghosh et al., 2019 ). The trypsin digested proteins products were fractionated using LC-MS/MS.…”

Association of CYP19A1 rs28757157 polymorphism with lung cancer risk in the Chinese Han population

“…Statistical and bioinformatics results highlighted the important roles of rs28757157, rs3751592, and rs59429575 in the outset of lung cancer in the total or stratified population, which helped improve our understanding of CYP19A1 in this disease. CYP19A1 gene, encoding aromatase and responsible for the final step in the biosynthesis of estrogens, estradiol (E2) and estrone (E1), has been intensively investigated [25,26]. It has been identified that SNPs in the intron region of CYP19A1 play an important role in the transcriptional regulation and splicing of CYP19A1 and could produce some different enzymes with diverse enzyme activity compared with normal gene products [27].…”

In the mouse, prostaglandin D2 signalling protects the endometrium against adenomyosis

“…The increased PGE2 production in L/H-Pgds -/-uteri might be linked to the up-regulation of StAR that encodes the rate-limiting factor in steroid biosynthesis; however, Scc and Cyp19a1 transcriptional levels were not changed. CYP19a1 upregulation in L/H-Pgds -/-uteri, without any transcriptional modification of the gene expression via PGE2 (Attar et al, 2009), suggests that PGD2 might be involved in CYP19a1 post-transcriptional/translational regulation or in the regulation of its stability (Ghosh et al, 2019, Molehin et al, 2018. Together with CYP19a1 upregulation, the modified expression of HSD17B2 and HSD17B7, two E2 metabolic enzymes, suggests that the local oestrogen metabolism is modified in the absence of PGD2, as reported in human endometriosis (Attar et al, 2009, Delvoux et al, 2009, Huhtinen et al, 2012b and adenomyosis (Kitawaki, 2006, Maia et al, 2006, Takahashi et al, 1989.…”

“…Additional experiments (i.e. high-throughput transcriptomic analysis, in vitro analysis) are needed to evaluate the direct or indirect mechanisms initiated by PGD2 and involved in the post-transcriptional/translational regulation of ESR1-2, COX1, COX2, CYP19a1(Otto et al, 1993, Wada et al, 2009, Yu and Kim, 2012, Jaen et al, 2018, Molehin et al, 2018, Ghosh et al, 2019, thus affecting their expression, stability and/or their subcellular localisation.…”