Investigating the mechanoregulation mechanisms underlying comparative differences in placentation

A fundamental question in biology is how cells maintain their proper position within tissues. Tissues are organized into distinct compartments, an epithelial layer and the underlying connective tissue, or stroma, and the boundary between them is normally held in tight balance. In certain healthy processes, including pregnancy, wound healing, and embryonic development, cells must cross this boundary in a precisely controlled way. Understanding the cellular and molecular mechanisms that govern this control is the central goal of this research. This project uses placentation as a natural model system. Placental cells invade maternal tissue deeply in some mammals, such as humans, yet this invasion is almost entirely resisted in others, such as cattle and pigs. This remarkable diversity allows the project to ask how stromal cells actively regulate invasion through physical forces and intracellular signaling, rather than acting as a passive barrier as long assumed. By elucidating these mechanisms, the project promotes the progress of science and advances understanding of how tissue organization is established and maintained. This project would develop a new curriculum and a standalone course in the emerging field of systems mechanobiology, providing sustained mentored research experiences for undergraduate college students. The project also involves conducting K-12 STEM outreach aimed at broadening participation in science. This project tests the hypothesis that the position of the epithelial-stromal boundary is a collective biomechanical phenotype, governed not only by invading cells, the long-presumed sole agents, but also by the active, evolved mechanical response of stromal fibroblasts. The work pursues two aims. The first establishes Anisotropic Monolayer Stress Microscopy (AMSM), an engineered platform. This platform couples a quantitative, nanopatterned invasion assay with traction and intercellular force microscopy on optically transparent hydrogels. The platform enables simultaneous measurement of invasion, mechanical stress, and live-cell signaling at a heterotypic cell-cell interface. The second aim integrates comparative transcriptomics across mammalian species, cis-regulatory analysis of transcription-factor binding sites, gene perturbation, and quantitative functional assays. The results of this aim would identify the molecular signaling modules that distinguish invasion-resistant from invasion-permissive stroma. The work centers on the Protein Kinase A (PKA) pathway and the mechanosensitive ion channel Piezo1. The experimental design is intended to resolve how a candidate PKA–Piezo1 axis connects mechanosensation to cellular contractility and force generation, together with species differences in extracellular matrix composition. By combining engineered materials and nanofabrication with comparative genomics and quantitative cell mechanics, the project aims to deliver a mechanistic, systems-level framework for how stromal biomechanics and signaling regulate the epithelial-stromal boundary. The project intends to yield principles that emerge from, and extend beyond, the comparative study of placentation, with implications for cell invasion in development, tissue repair, and disease. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria. NSF Award ID: 2617539 | Program: 01002627DB NSF RESEARCH & RELATED ACTIVIT | Principal Investigator: FNU Kshitiz | Institution: University of Connecticut Health Center, FARMINGTON, CT | Award Amount: $601,728 View on NSF Award Search: https://www.nsf.gov/awardsearch/show-award/?AWD_ID=2617539 View on Research.gov: https://www.research.gov/awardapi-service/v1/awards/2617539.html