Biology subjects

Soares, M. J.

Publications and source records attributed to Soares, M. J..

10 recordsLinked to original sources

bioRxiv2025

PPARG directs trophoblast cell fate and establishment of the uterine-placental interface

The expansion and differentiation of trophoblast stem (TS) cells are critical for defining fundamental properties of the placenta. Specialized trophoblast cells exit the placenta and enter and transform the uterus, including restructuring uterine spiral arteries. In the human these cells are named extravillous trophoblast (EVT) cells, whereas in the rat they are termed invasive trophoblast cells. Mechanisms governing invasive trophoblast cell differentiation remain poorly understood. We investigated peroxisome proliferator-activated receptor gamma (PPARG) as a potential regulator of EVT/invasive trophoblast cell development. In first trimester human placentas, PPARG was expressed in the EVT cell column and increased in amount as human TS cells differentiated into EVT cells. PPARG disruption impaired EVT cell differentiation. Rat invasive trophoblast cells similarly expressed PPARG. Conditional inactivation of PPARG within rat invasive trophoblast cells was used to assess the in vivo role of PPARG on the uterine-placental interface. PPARG was established as an essential cell-autonomous regulator of the invasive trophoblast cells. In conclusion, PPARG is a conserved regulator of placentation and is essential for directing trophoblast cell-guided uterine transformation.

developmental biology↗

bioRxiv2024

Effects Of Aryl Hydrocarbon Receptor Ligand TCDD On Human Trophoblast Cell Development

STUDY QUESTIONHow does activation of AHR signaling affect human trophoblast cell development and differentiation? SUMMARY ANSWERAHR activation leads to altered gene expression but does not hinder the ability of trophoblast cells to remain in a stem cell state or differentiate into essential cell types, such as extravillous trophoblast cells (EVT) or syncytiotrophoblast (ST). It also promotes the production of 2 methoxy estradiol (2ME), a compound that could influence placental development. WHAT IS KNOWN ALREADYThe placenta serves both as a nutrient delivery system and a protective barrier against environmental toxins. AHR signaling is known to mediate cellular responses to environmental pollutants, potentially affecting trophoblast cell functions, but the specific impacts of AHR activation on these cells were not fully understood. STUDY DESIGN, SIZE, DURATIONThis study utilized an in vitro model of human trophoblast stem (TS) cells to investigate the downstream effects of AHR activation. The study focused on both undifferentiated TS cells and cells undergoing differentiation. PARTICIPANTS/MATERIALS, SETTING, METHODSHuman trophoblast stem (TS) cells were used as the model system. Researchers examined the effects of TCDD exposure in both TS cells maintained in their stem state and those induced to differentiate into EVT or ST. The study assessed changes in gene expression, particularly focusing on CYP1A1 and CYP1B1, as well as the production of 2ME. MAIN RESULTS AND THE ROLE OF CHANCEAHR activation stimulated the expression of CYP1A1 and CYP1B1, key genes associated with AHR signaling, in both undifferentiated and differentiating trophoblast cells. While AHR activation did not impact the cells ability to remain in a stem state or differentiate, it increased the production of 2ME, which may influence placental function. These effects were dependent on AHR signaling. LIMITATIONS, REASONS FOR CAUTIONThis study was conducted in vitro, which may not fully replicate human conditions. Further research is needed to confirm whether these findings apply to actual placental development in humans. WIDER IMPLICATIONS OF THE FINDINGSThe results suggest that AHR signaling activated by environmental pollutants could have a subtle but significant impact on placental development through mechanisms involving AHR activation. These findings may have broader implications for understanding how environmental factors affect fetal development. STUDY FUNDING/COMPETING INTEREST(S)This work was funded by the National Institutes of Health: ES028957, HD020676, ES029280, HD105734 and the Sosland Foundation. The authors declare no conflicts of interest.

developmental biology↗

bioRxiv2024

NOTUM-MEDIATED WNT SILENCING DRIVES EXTRAVILLOUS TROPHOBLAST CELL LINEAGE DEVELOPMENT

Trophoblast stem (TS) cells have the unique capacity to differentiate into specialized cell types, including extravillous trophoblast (EVT) cells. EVT cells invade into and transform the uterus where they act to remodel the vasculature facilitating the redirection of maternal nutrients to the developing fetus. Disruptions in EVT cell development and function are at the core of pregnancy-related disease. WNT-activated signal transduction is a conserved regulator of morphogenesis of many organ systems, including the placenta. In human TS cells, activation of canonical WNT signaling is critical for maintenance of the TS cell stem state and its downregulation accompanies EVT cell differentiation. We show that aberrant WNT signaling undermines EVT cell differentiation. Notum, palmitoleoyl-protein carboxylesterase (NOTUM), a negative regulator of canonical WNT signaling, was prominently expressed in first trimester EVT cells developing in situ and upregulated in EVT cells derived from human TS cells. Furthermore, NOTUM was required for optimal human TS cell differentiation to EVT cells. Activation of NOTUM in EVT cells is driven, at least in part, by endothelial PAS domain 1 (also called hypoxia-inducible factor 2 alpha). Collectively, our findings indicate that canonical WNT signaling is essential for maintenance of human trophoblast cell stemness and regulation of human TS cell differentiation. Downregulation of canonical WNT signaling via the actions of NOTUM is required for optimal EVT cell differentiation. SIGNIFICANCEExtravillous trophoblast (EVT) cells play a critical role in transforming the uterine environment into a supportive organ facilitating embryonic/fetal development. Insufficient EVT cell-dependent uterine transformation can lead to obstetrical complications, including early pregnancy loss, preeclampsia, intrauterine growth restriction, and preterm birth. These complications carry a significant burden of morbidity and mortality for both the mother and the fetus. Notum, palmitoleoyl-protein carboxylesterase, a WNT signaling antagonist, is involved in promoting and maintaining EVT cell differentiation. This process is essential for the proper development of the placenta and is crucial for a healthy pregnancy.

developmental biology↗

bioRxiv2023

TAF7L REGULATES EARLY STAGES OF MALE GERM CELL DEVELOPMENT

Male germ cell development is dependent on the orchestrated regulation of gene networks. TATA-box binding protein associated factors (TAFs) facilitate interactions of TATA-binding protein with the TATA element, which is known to coordinate gene transcription during organogenesis. TAF7 like (Taf7l) is situated on the X chromosome and has been implicated in testis development. We examined the biology of TAF7L in testis development using the rat. Taf7l was prominently expressed in preleptotene to leptotene spermatocytes. To study the impact of TAF7L on the testis we generated a global loss-of-function rat model using CRISPR/Cas9 genome editing. Exon 3 of the Taf7l gene was targeted. A founder was generated possessing a 110 bp deletion within the Taf7l locus, which resulted in a frameshift and the premature appearance of a stop codon. The mutation was effectively transmitted through the germline. Deficits in TAF7L did not adversely affect pregnancy or postnatal survival. However, the Taf7l disruption resulted in male infertility due to compromised testis development and failed sperm production. Mutant germ cells suffer meiotic arrest at the zygotene stage, with defects in sex body formation and meiotic sex chromosome inactivation. This testis phenotype was more pronounced than previously described for the subfertile Taf7l null mouse. We conclude that TAF7L is essential for male germ cell development in the rat.

developmental biology↗

bioRxiv2023

CORE CONSERVED TRANSCRIPTIONAL REGULATORY NETWORKS DEFINE THE INVASIVE TROPHOBLAST CELL LINEAGE

The invasive trophoblast cell lineage in rat and human share crucial responsibilities in establishing the uterine-placental interface of the hemochorial placenta. These observations have led to the rat becoming an especially useful animal model to study hemochorial placentation. However, our understanding of similarities or differences between regulatory mechanisms governing rat and human invasive trophoblast cell populations is limited. In this study, we generated single-nucleus (sn) ATAC-seq data from gestation day (gd) 15.5 and 19.5 rat uterine-placental interface tissues and integrated the data with single-cell RNA-seq data generated at the same stages. We determined the chromatin accessibility profiles of invasive trophoblast, natural killer, macrophage, endothelial, and smooth muscle cells, and compared invasive trophoblast chromatin accessibility to extravillous trophoblast (EVT) cell accessibility. In comparing chromatin accessibility profiles between species, we found similarities in patterns of gene regulation and groups of motifs enriched in accessible regions. Finally, we identified a conserved gene regulatory network in invasive trophoblast cells. Our data, findings and analysis will facilitate future studies investigating regulatory mechanisms essential for the invasive trophoblast cell lineage.

developmental biology↗

bioRxiv2022

Conservation at the uterine-placental interface

The hemochorial placentation site is characterized by a dynamic interplay between trophoblast cells and maternal cells. These cells cooperate to establish an interface required for nutrient delivery to promote fetal growth. In the human, trophoblast cells penetrate deep into the uterus. This is not a consistent feature of hemochorial placentation and has hindered the establishment of suitable animal models. The rat represents an intriguing model for investigating hemochorial placentation with deep trophoblast cell invasion. In this study, we used single cell RNA sequencing to characterize the transcriptome of the invasive trophoblast cell lineage, as well as other cell populations within the rat uterine-placental interface during early (gestation day, gd, 15.5) and late (gd 19.5) stages of intrauterine trophoblast cell invasion. We identified a robust set of transcripts that define invasive trophoblast cells, as well as transcripts that distinguished endothelial, smooth muscle, natural killer, and macrophage cells. Invasive trophoblast, immune, and endothelial cell populations exhibited distinct spatial relationships within the uterine-placental interface. Furthermore, the maturation stage of invasive trophoblast cell development could be determined by assessing gestation-stage dependent changes in transcript expression. Finally, and most importantly, expression of a prominent subset of rat invasive trophoblast cell transcripts is conserved in the invasive extravillous trophoblast cell lineage of the human placenta. These findings provide foundational data to identify and interrogate key conserved regulatory mechanisms essential for development and function of an important compartment within the hemochorial placentation site that is essential for a healthy pregnancy. SIGNIFICANCETrophoblast cell-guided restructuring of the uterus is an essential event in the establishment of the hemochorial placenta. Establishment of a suitable animal model for investigating regulatory mechanisms in this critical developmental process is a key to better understanding the etiology of diseases of placentation, such as early pregnancy loss, preeclampsia, intrauterine growth restriction, and preterm birth. The rat exhibits deep trophoblast cell invasion, as seen in human hemochorial placentation. Similarities are identified in the transcriptomes of rat and human invasive trophoblast cells, leading to the discovery of conserved candidate regulators of the invasive trophoblast cell lineage. This creates opportunities to test hypotheses underlying the pathophysiologic basis of trophoblast cell-guided uterine transformation and new insights into the etiology of diseases of placentation.

developmental biology↗

bioRxiv2022

AKT1-FOXO4 AXIS REGULATES HEMOCHORIAL PLACENTATION

Hemochorial placentation involves the differentiation of specialized cells called invasive trophoblast cells possessing the capacity to exit the placenta and invade into the uterus where they restructure the vasculature. Invasive trophoblast cells arise from a well-defined compartment within the placenta, referred to as the junctional zone in the rat and the extravillous trophoblast cell column in the human. In this study, we investigated roles for AKT1, a serine/threonine kinase, in placental development using a genome-edited/loss-of-function rat model. Disruption of AKT1 resulted in placental, fetal, and postnatal growth restriction. Forkhead box O4 (Foxo4), which encodes a transcription factor and known AKT substrate, was abundantly expressed in the junctional zone and invasive trophoblast cells of the rat placentation site. Foxo4 gene disruption using genome-editing resulted in placentomegaly, including an enlarged junctional zone. AKT1 and FOXO4 regulate the expression of many of the same transcripts expressed by trophoblast cells; however, in opposite directions. In summary, we have identified AKT1 and FOXO4 as part of a regulatory network that reciprocally controls critical indices of hemochorial placenta development. SUMMARY STATEMENTGenome-edited rat models were utilized to investigate roles for AKT1 and FOXO4 in hemochorial placentation. AKT1 and FOXO4 possess reciprocal actions in regulating development of the hemochorial placenta.

developmental biology↗

bioRxiv2022

CITED2 Is A Conserved Regulator Of Deep Hemochorial Placentation

Establishment of the hemochorial uterine-placental interface requires exodus of trophoblast cells from the placenta and their transformative actions on the uterus, which represent processes critical for a successful pregnancy, but are poorly understood. We examined the involvement of CBP/p300-interacting transactivator with glutamic acid/aspartic acid-rich carboxyl terminal domain 2 (CITED2) in rat and human trophoblast cell development. The rat and human exhibit deep hemochorial placentation. CITED2 was distinctively expressed in the junctional zone and invasive trophoblast cells of the rat. Homozygous Cited2 gene deletion resulted in placental and fetal growth restriction. Small Cited2 null placentas were characterized by disruptions in the junctional zone, delays in intrauterine trophoblast cell invasion, and compromised plasticity. In the human placentation site, CITED2 was uniquely expressed in the extravillous trophoblast (EVT) cell column and importantly contributed to development of the EVT cell lineage. We conclude that CITED2 is a conserved regulator of deep hemochorial placentation. Significance StatementThe process of establishing the uterine-placental interface is a poorly understood tissue re-engineering event that involves genetically foreign trophoblast cells breaching the immunologically secure uterus. When optimal, mother and fetus thrive, whereas failures represent the root cause of life-threatening diseases of pregnancy. CBP/p300-interacting transactivator with glutamic acid/aspartic acid-rich carboxyl terminal domain 2 (CITED2) is a transcriptional co-regulator with a conspicuous presence in trophoblast cell lineages infiltrating the uterine parenchyma. CITED2 helps coordinate the differentiation of rat and human trophoblast cells into invasive/extravillous trophoblast cells capable of transforming the uterus. These actions ensure requisite placental development and adaptations to physiological stressors. CITED2 exemplifies a conserved regulator of transcriptional events essential for establishing the uterine-placental interface.

developmental biology↗

bioRxiv2020

AKT-like kinase promotes cell survival during nutritional stress in tripanosomatids

Tritryps are protozoan parasites that belong to the Trypanosomatidae family, which encompasses the etiologic agents of leishmaniasis, African and American trypanosomiasis. These parasites undergo different stress conditions across their life cycle, such as nutritional stress, which needs to be deadened in order to guarantee the survival of the parasite inside its vector and mammal hosts. Here we show that the lack of the serine threonine kinase PKB / AKT-like function, either by allosteric inhibition of its Plekstrin domain (PH) in T. cruzi, the reduction of the gene transcripts in T. brucei by RNAi assays, or by AKT-like gene knockout in L. major, reduce the tolerance to nutritional stress of parasites that triggers apoptosis-like events, including DNA fragmentation, mitochondrial damage and loss of plasma membrane integrity. Additionally, we observed that double knockout of Akt-like in L. major impairs its infective capacity. This work confirms some of the previously described functions regarding parasite survival for AKT-like kinases in the Leishmania genus. The present work also provides strong evidence of the probable function of Akt-like in T. cruzi and T. brucei survival and infectivity. Author summaryEndemic countries for neglected tropical diseases are called to play a paramount role in the discovery of new drug candidates through the application of new drug development strategies. Rational drug design method have proven to be compatible with the development of new drug for orphan and neglected diseases since it substantially reduces the costs of discovery and development, a desirable condition for public funded initiatives. Previously we have identified a new parasite protein kinase (AKT-like) as promising new target candidate by means of computational tools and probed its biological role in trypanosomatids. Here we show that inhibition of the AKT-like kinase in trypanosomatids by different approaches (chemical inhibition, interference RNA and gene knockout) decreases the fitness and survival of the parasites in vitro, interfering with the capacity of the parasites to react and survive stress conditions similar to those experienced by the cell in the natural life cycle. Additionally our results strongly supports the potential of a new family of compounds previously described by bioinformatics means as potential trypanocidal agents. Altogether we show that the specific inhibition of the AKT-like is a promising strategy for the further development of anti-trypanosome drugs.

microbiology↗

bioRxiv2020

Downregulation of the essential Rrp44 ribonuclease causes extensive ultra-structure cell modifications in Trypanosoma brucei

Rrp44/Dis3 is an essential protein conserved in all eukaryotes that functions in the maturation of many different RNA precursors and RNA surveillance. The Trypanosoma brucei Rrp44/Dis3 homologue (TbRRP44) is required for maturation of pre-rRNA, spliced leader, and U3 snoRNA precursors. Its depletion leads to inhibition of cell proliferation and eventually to cell death. In this work, we showed that TbRRP44 depletion causes a massive expansion of acidic and lysosome-derived vacuoles, enlargement of cell and nuclei sizes without changes in DNA content, mitochondrial inactivation, and autophagy induction. Consistently, 3D reconstructions using cryo-soft X-ray tomography revealed extreme vacuolation of the cytoplasm and numerous cellular alterations, including an increase in size and number of calcium-containing vesicles and lipid droplets. These multiple defects indicate that a combination of alterations converge to induce lysosome expansion. With time, the cytoplasm is taken up by lysosome-derived vacuoles, which may be a final stage leading to the cell death triggered by TbRRP44 depletion. These studies provide the first evidence on the ultra-structure cell modifications caused by deficiency of this essential ribonuclease in T. brucei.

cell biology↗