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ACKNOWLEDGMENTS

We thank I. Matos for assistance with the live-imaging

setup; L. Hidalgo and M. Sribour for animal assistance; and

S. Ellis and I. Matos for discussion and comments on the

manuscript. We thank the Molecular Cytology Core Facility at

MSKCC and Rockefeller University (RU) Bio-Imaging

Resource Center for use of microscopes, and RU Comparative

Bioscience Center (AAALAC-accredited) for care of mice

in accordance with National Institutes of Health (NIH)

guidelines.Funding:This work was funded by NIH (R01-

AR27883 to E.F.) and partly supported by the Robertson

Therapeutic Development Fund and by a Tri-Institutional Starr

Stem Cell Scholars Fellowship at The Rockefeller University.

E.F. is an HHMI investigator. F.G.Q. holds a Career Award

at the Scientific Interface from Burroughs Wellcome Fund.

Author contributions:F.G.Q. and E.F. conceived the project,

designed the experiments, and interpreted the data. F.G.Q. and

Quirozet al.,Science 367 , eaax9554 (2020) 13 March 2020 11 of 12

RESEARCH | RESEARCH ARTICLE