Overview

• The Piotrowski Lab identified two cyclin D genes, ccnd2a and ccndx, that separately control proliferation in zebrafish neuromast stem and progenitor support cells.
• Targeted knockouts showed that loss of each gene halted division only in its specific cell population, confirming independent regulation of stem and progenitor pools.
• Cross-expression of the stem cell–specific cyclin D gene in progenitor cells restored their division, uncoupling differentiation from cell-cycle entry.
• Building on Nature Communications findings published July 14, teams are testing whether activating these cyclin D pathways can trigger hair cell regeneration in mammalian models.
• Insights into cyclin D–mediated proliferation carry implications for broader regenerative medicine applications and underscore safety considerations for human therapies.