The Hippo pathway regulates organ size, regeneration, and cell growth by controlling the stability of the transcription factor, YAP (Yorkie in Drosophila). When there is tissue damage, YAP is activated allowing the restoration of homeostatic tissue size. The exact signals by which YAP is activated are still not fully understood, but its activation is known to affect both cell size and cell number. Here we used cultured cells to examine the coordinated regulation of cell size and number under the control of YAP. Our experiments in isogenic HEK293 cells reveal that YAP can affect cell size and number by independent circuits. Some of these effects are cell autonomous, such as proliferation, while others are mediated by secreted signals. In particular CYR61, a known secreted YAP target, is a non-cell autonomous mediator of cell survival, while another unidentified secreted factor controls cell size.
Sequencing data has been deposited in GEO under accession code GSE123296
Induction of YAP5SA-GFP vs nGFP expression in FlipinTrex293 cellsNCBI Gene Expression Omnibus, GSE123296.
- Marc W Kirschner
- Marc W Kirschner
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
- Duojia Pan, UT Southwestern Medical Center and HHMI, United States
© 2020, Mugahid et al.
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