Biology subjects

Sequeira-Lopez, M. L. S.

Publications and source records attributed to Sequeira-Lopez, M. L. S..

4 recordsLinked to original sources

bioRxiv2024

The transcription factor Tcf21 is required for specifying Foxd1 cells to the juxtaglomerular cell lineage

Renin is crucial for blood pressure regulation and electrolyte balance, and its expressing cells arise from Foxd1+ stromal progenitors. However, factors guiding these progenitors toward renin-secreting cell fate remain unclear. Tcf21, a basic helix-loop-helix (bHLH) transcription factor, is essential in kidney development. Utilizing Foxd1Cre/+;Tcf21f/f and Ren1dCre/+;Tcf21f/f mouse models, we investigated the role of Tcf21 in the differentiation of Foxd1+ progenitor cells into juxtaglomerular (JG) cells. Immunostaining and in-situ hybridization demonstrated fewer renin-positive areas and altered renal arterial morphology, including the afferent arteriole, in Foxd1Cre/+;Tcf21f/f kidneys compared to controls, indicating Tcf21s critical role in the emergence of renin-expressing cells. However, Tcf21 inactivation in renin-expressing cells (Ren1dCre/+;Tcf21f/f) did not recapitulate this phenotype, suggesting Tcf21 is dispensable once renin cell identity is established. Using an integrated analysis of single-cell RNA sequencing (scRNA-seq) and single-cell assay for transposase-accessible chromatin sequencing (scATAC-seq) on GFP+ cells (stromal lineage) from E12, E18, P5, and P30 Foxd1Cre/+;Rosa26mTmG control kidneys, we analyzed the temporal dynamics of Tcf21 expression in cells comprising the JG lineage (n=2,054). A pseudotime trajectory analysis revealed that Tcf21 expression is highest in metanephric mesenchyme and stromal cells at early developmental stages (E12), with a decline in expression as cells mature into renin-expressing JG cells. Motif enrichment analyses supported Tcf21s significant involvement in early kidney development. These findings underscore the critical role of Tcf21 in Foxd1+ cell differentiation into JG cells during early stages of kidney development, offering insights into the molecular mechanisms governing JG cell differentiation and highlight Tcf21s pivotal role in kidney development. NEW & NOTEWORTHYThis manuscript provides novel insights into the role of Tcf21 in the differentiation of Foxd1+ cells into JG cells. Utilizing integrated scRNA-seq and scATAC-seq, the study reveals that Tcf21 expression is crucial during early embryonic stages, with its peak at embryonic day 12. The findings demonstrate that inactivation of Tcf21 leads to fewer renin-positive areas and altered renal arterial morphology, underscoring the importance of Tcf21 in the specification of renin-expressing JG cells and kidney development.

developmental biology↗

bioRxiv2024

An efficient inducible model for the control of gene expression in renin cells

BackgroundFate mapping and genetic manipulation of renin cells have relied on either non-inducible Cre lines that can introduce developmental effects of gene deletion or BAC transgene-based inducible models that may be prone to spurious and/or ectopic gene expression. MethodsWe generated an inducible mouse model in which CreERT2 is under the control of the endogenous Akr1b7 gene, an independent marker of renin cells. ResultsWe evaluated the pattern of Cre expression in Akr1b7CreERT2/+;R26RmTmG/+ mice in which Akr1b7+/renin+ cells become GFP+ upon tamoxifen administration. At E18.5 and P5, GFP was found in Juxtaglomerular cells, along the arterioles, and in the glomerular mesangium. In adult kidneys, GFP was present mainly in Juxtaglomerular cells. In mice treated with captopril and a low sodium diet to induce recruitment of renin cells, GFP extended along the afferent arterioles and in the mesangium. In addition, we deleted renin in adult mice and found a marked reduction in kidney renin expression and mean arterial pressure in mutant animals. When subjected to a homeostatic threat, mutant mice were unable to recruit renin+ cells. Most importantly, mice with renin deletion induced in the adult developed concentric vascular hypertrophy ruling out potential developmental effects on the vasculature due to the lack of renin. ConclusionsRenin can be efficiently and specifically deleted in renin cells in adult life using our conditional model. Akr1b7CreERT2 mice constitute an excellent model for the fate mapping of renin cells and for the spatial and temporal control of gene expression in renin cells.

physiology↗

bioRxiv2023

Protein Kinase A Inhibition Epigenetically Silences Ren1

RationaleRenin-expressing cells are myoendocrine cells crucial for survival which detect changes in blood pressure and release renin to maintain homeostasis. One of the pathways responsible for renin expression includes cAMP as a crucial factor. cAMP binds to subunits of protein kinase A (PKA), ultimately recruiting both CBP and p300. Binding to the cAMP-responsive element in the renin enhancer region thus amplifies renin transcription. ObjectiveTo evaluate transcriptomic and epigenomic changes occurring at the renin locus via cAMP pathway inhibition. Methods and ResultsWe treated As4.1 cells (a tumoral cell line that constitutively expresses renin) with the PKA inhibitor H89 (treated) or DMSO (control). We then performed independent ATAC-seq, scRNA-seq, and ChIP-seq for H3K27Ac and P300 binding on biological replicates of treated and control As4.1 cells. Ren1 expression is significantly reduced following PKA inhibition with a corresponding loss in H3K27Ac and P300 binding at the locus. A restricted set of nine genes with overlapping dynamically accessible regions, differential gene expression, and H3K27Ac and P300 binding were identified with roles among three primary renin regulatory paradigms. ConclusionsThe data suggests that cAMP pathway inhibition controls renin expression through a reduction not in accessibility alone, but via a switch from an active to poised state of epigenetic control, a shift towards a less differentiated cellular identity, and the disruption of not only cAMP, but baroreceptor and Notch mediated renin regulatory pathways.

genomics↗

bioRxiv2023

Determinants of renin cell differentiation: a single cell epi-transcriptomics approach

RationaleRenin cells are essential for survival. They control the morphogenesis of the kidney arterioles, and the composition and volume of our extracellular fluid, arterial blood pressure, tissue perfusion, and oxygen delivery. It is known that renin cells and associated arteriolar cells descend from FoxD1+ progenitor cells, yet renin cells remain challenging to study due in no small part to their rarity within the kidney. As such, the molecular mechanisms underlying the differentiation and maintenance of these cells remain insufficiently understood. ObjectiveWe sought to comprehensively evaluate the chromatin states and transcription factors (TFs) that drive the differentiation of FoxD1+ progenitor cells into those that compose the kidney vasculature with a focus on renin cells. Methods and ResultsWe isolated single nuclei of FoxD1+ progenitor cells and their descendants from FoxD1cre/+;R26R-mTmG mice at embryonic day 12 (E12) (ncells=1234), embryonic day 18 (E18) (ncells=3696), postnatal day 5 (P5) (ncells=1986), and postnatal day 30 (P30) (ncells=1196). Using integrated scRNA-seq and scATAC-seq we established the developmental trajectory that leads to the mosaic of cells that compose the kidney arterioles, and specifically identified the factors that determine the elusive, myo-endocrine adult renin-secreting juxtaglomerular (JG) cell. We confirm the role of Nfix in JG cell development and renin expression, and identified the myocyte enhancer factor-2 (MEF2) family of TFs as putative drivers of JG cell differentiation. ConclusionsWe provide the first developmental trajectory of renin cell differentiation as they become JG cells in a single-cell atlas of kidney vascular open chromatin and highlighted novel factors important for their stage-specific differentiation. This improved understanding of the regulatory landscape of renin expressing JG cells is necessary to better learn the control and function of this rare cell population as overactivation or aberrant activity of the RAS is a key factor in cardiovascular and kidney pathologies.

developmental biology↗