Biology subjects

Cai, C.-L.

Publications and source records attributed to Cai, C.-L..

3 recordsLinked to original sources

bioRxiv2025

ZEB2 signaling is essential for ureteral smooth muscle cell differentiation and maintenance

Mowat-Wilson Syndrome (MWS) is a multiple congenital anomaly syndrome caused by mutations in the ZEB2, which plays a critical role in cell fate determination and differentiation during development. Congenital anomalies of the kidney and urinary tract (CAKUT) have been reported in MWS patients. However, the role of ZEB2 in urinary tract development and the cellular and molecular mechanism underlining the CAKUT phenotypes in MWS remains unknown. We performed ZEB2 protein expression analysis in the developing mouse ureter. We generated Zeb2 ureteral mesenchyme-specific conditional knockout mice by crossing Zeb2 floxed mice with Tbx18Cre mice (Zeb2 cKO) and analyzed the urinary tract phenotypes in Zeb2 cKO mice and wild-type littermate controls by gross and histological examination. Ureteral cellular and molecular phenotypes were studied using TAGLN, ACTA2, FOXD1, POSTN, CDH1, TBX18, and SOX9 ureteral cell-specific markers. We found that ZEB2 is expressed in TBX18+ ureteral mesenchymal cells during mouse ureter development. Deletion of Zeb2 in developing ureteral mesenchymal cells causes hydroureter and hydronephrosis phenotypes, leading to obstructive uropathy, kidney failure, and early mortality. Cellular and molecular marker analyses showed that the TAGLN+ACTA2+ ureteral smooth muscle cells (SMCs) layer is not formed in Zeb2 cKO mice at E15.5, but the FOXD1+ and POSTN+ tunica adventitia cells layer is significantly expanded compared to wild-type controls. CDH1+ urothelium cells are reduced considerably in the Zeb2 cKO ureters at E15.5. Mechanistically, we found that Zeb2 cKO mice have significantly decreased TBX18 expression but an increased SOX9 expression in the developing ureter at E14.5 and E15.5 compared to wild-type littermate controls. Our results show that ZEB2 is essential for ureter development by maintaining ureteral mesenchymal cell differentiation into normal ureteral SMCs. Our study also shed new light on the pathological mechanism underlying the developmental abnormalities of the urinary tract phenotypes in MWS patients. Author SummaryHydroureter and hydronephrosis are common congenital anomalies with high incidence (1:100 to 1:500) that can lead to obstructive uropathy and renal failure in the pediatric population. Mowat-Wilson Syndrome (MWS), caused by heterozygous mutations in the ZEB2 gene, is a genetic disease with multiple congenital developmental defects, including hydroureter and hydronephrosis. However, the molecular function of ZEB2 in ureter development and pathogenesis of hydroureter and hydronephrosis remains unknown. Here, we show that ZEB2 is expressed in the developing ureteral mesenchymal cells, and deletion of ZEB2 in ureteral mesenchymal cells leads to ureteral smooth muscle cell loss, which is replaced by tunica adventitia cells causing hydroureter and hydronephrosis phenotype. Hence, our work not only demonstrates the critical role of ZEB2 in ureter development but also provides molecular mechanisms of urinary tract anomalies in MWS patients.

developmental biology↗

bioRxiv2024

Generation of a novel constitutive smooth muscle cell-specific Myh11-driven Cre mouse model

Dysfunction in either embryonic or postnatal vascular smooth muscle cells (SMCs) significantly contributes to the progression of various cardiovascular diseases. Therefore, elucidating the molecular mechanisms governing VSMC development and homeostasis is crucial. MYH11 is the most reliable lineage gene for SMCs and has been utilized to develop tamoxifen-inducible Cre driver lines for achieving SMC-specific gene manipulation by crossing with mice carrying the loxP-flanked gene, particularly in adult mice. For studies involving SMCs during embryogenesis, the commonly used constitutive Cre driver is controlled by the Tagln (Sm22) promoter. However, this Cre driver exhibits activity in multiple non-SMC populations, including cardiomyocytes and skeletal muscle precursors, introducing confounding effects. Additionally, most existing SMC-specific Cre drivers are generated using a transgenic approach, raising concerns about random site integration and variable gene copy numbers. To address these limitations, we report a novel Cre mouse model generated by knock-in (KI) of a nuclear-localized Cre recombinase into the Myh11 gene locus using homologous recombination. We confirmed that the Cre activity precisely recapitulates endogenous Myh11 expression by crossing with Rosa26 mTmG or tdTomato reporter mice. Moreover, Myh11-driven Cre can efficiently delete the floxed allele of the transcription factor Tead1 specifically in SMCs. The Tead1 SMC-specific knockout mice did not exhibit an overt phenotype, thereby circumventing the embryonic lethal phenotype mediated by Tagln-driven Cre, as we previously reported. These findings establish this novel Cre driver line as a robust tool for tracing the Myh11-positive SMC lineage and manipulating gene function specifically in SMCs during embryonic development in mice.

genetics↗

bioRxiv2023

Endocardial HDAC3 is required for myocardial trabeculation

Failure of proper ventricular trabeculation is often associated with congenital heart disease (CHD). Support from endocardial cells, including the secretion of extracellular matrix (ECM) and growth factors is critical for trabeculation. However, it is poorly understood how the secretion of ECM and growth factors is initiated and regulated by endocardial cells. We found that genetic knockout (KO) of histone deacetylase 3 (Hdac3) in the endocardium in mice resulted in early embryo lethality and ventricular hypotrabeculation. Single cell RNA sequencing identified significant downregulation of ECM components in Hdac3 KO endocardial cells. Secretome from cultured Hdac3 KO mouse cardiac endothelial cells lacked transforming growth factor {beta}3 (TGF{beta}3) and showed significantly reduced capacity in stimulating cultured cardiomyocyte proliferation, which was remarkably rescued by TGF{beta}3 supplementation. Mechanistically, we identified that HDAC3 induced Tgf{beta}3 expression through repressing microRNA (miR)-129-5p. Our findings provide novel insights into the pathogenesis of CHD and conceptual strategies to promote myocardial regeneration.

developmental biology↗