# EMT, Tailbud Biomechanics and Spinal Column Symmetry

> **NIH NIH R01** · YALE UNIVERSITY · 2021 · $335,000

## Abstract

The vertebrate tailbud is a dynamic growth zone that gives rise to the trunk and tail. During body
elongation, motile tailbud cells undergo an order to disorder transition via EMT as they become
mesodermal progenitors and sort into the left and right paraxial mesoderm. Combining
quantitative in vivo cell tracking with modeling of cell migration in a tailbud-like geometry, the
research group identified anisotropic left-right fluxes after EMT as cells sort into the paraxial
mesoderm. At any single timepoint, cell flux is typically asymmetric. This pattern represents
intermittent collective cell migration within the disordered mesodermal progenitor domain. The
increased disorder in cell motion after EMT frequently switches the direction of the anisotropic
cell flows which ensures bilateral symmetry of the spinal column. A two-pronged approach is
used to understand the mechanism of symmetric body elongation. The first approach is to
identify downstream effectors of the Fgf, Wnt and Bmp signaling pathways that work in
conjunction with Cadherin 2 to govern the order to disorder transition in cell motion. Second, the
research group examines the general roles of cell adhesion, cytoskeletal contractility and cell
polarity in tailbud cell motion. The group will use in silico and in vivo analysis to define the cross-
scale mechanism by which noisy genetic and biophysical interactions between cells, acting at
different time-scales, produce episodic bilaterally asymmetric collective cell migration at the
scale of a few cells that is integrated over time to symmetrically disperse thousands of cells into
the paraxial mesoderm.

## Key facts

- **NIH application ID:** 10150031
- **Project number:** 5R01GM129149-04
- **Recipient organization:** YALE UNIVERSITY
- **Principal Investigator:** SCOTT A HOLLEY
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2021
- **Award amount:** $335,000
- **Award type:** 5
- **Project period:** 2018-09-04 → 2023-05-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10150031

## Citation

> US National Institutes of Health, RePORTER application 10150031, EMT, Tailbud Biomechanics and Spinal Column Symmetry (5R01GM129149-04). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10150031. Licensed CC0.

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