Characterization of Fetal Specific Transcriptional Programs in Thymic Epithelial Cells Identifies Myc as a Critical Determinant of Thymus Size [single cell RNA-Seq]

The thymus is the site of T cell development. Although much is known about the development and differentiation of the T lymphocyte compartment, less is known about the thymic epithelial cell (TEC) populations fostering their development. Here we use next generation sequencing approaches to identify transcriptional programs unique to TEC at specific stages of mouse life. This strategy identified Myc as a regulator of the fetal program, driving the rapid expansion in thymic size during fetal life. Overall design: Next-generation sequencing approaches on a large data set enabled the identification of age-specific transcriptional programs; and established a key role for Myc in driving TEC proliferation, ribosomal biogenesis, and regulating thymic size.