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bioRxiv · 10.1101/2020.01.13.891630

Single-cell transcriptome analysis reveals cell-cell communication and thyrocyte diversity in the zebrafish thyroid gland

Gillotay, P.·Shankar, M. P.·Eski, S. E.·Reinhardt, S.·Kraenkel, A.·Blaesche, J.·Petzold, A.·Kesavan, G.·Lange, C.·Brand, M.·Detours, V.·Costagliola, S.·Singh, S. P.
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Abstract

The thyroid gland regulates growth and metabolism via production of thyroid hormone in follicles composed of thyrocytes. So far, thyrocytes have been assumed to be a homogenous population. To uncover genetic heterogeneity in the thyrocyte population, and molecularly characterize the non-thyrocyte cells surrounding the follicle, we developed a single-cell transcriptome atlas of the zebrafish thyroid gland. The 6249-cell atlas includes profiles of thyrocytes, blood vessels, lymphatic vessels, immune cells and fibroblasts. Further, the thyrocytes could be split into two sub-populations with unique transcriptional signature, including differential expression of the transcription factor pax2a. To validate thyrocyte heterogeneity, we generated a CRISPR/Cas9-based pax2a knock-in line, which demonstrated specific pax2a expression in the thyrocytes. However, a population of pax2a-low mature thyrocytes interspersed within individual follicles could be distinguished, corroborating heterogeneity within the thyrocyte population. Our results identify and validate transcriptional differences within the nominally homogenous thyrocyte population. One-line summarySingle-cell analysis uncovers latent heterogeneity in thyroid follicular cells. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=74 SRC="FIGDIR/small/891630v2_ufig1.gif" ALT="Figure 1"> View larger version (17K): org.highwire.dtl.DTLVardef@f6df3org.highwire.dtl.DTLVardef@fb8c59org.highwire.dtl.DTLVardef@bb5be1org.highwire.dtl.DTLVardef@8d174e_HPS_FORMAT_FIGEXP M_FIG C_FIG

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Gillotay, P., Shankar, M. P., Eski, S. E., Reinhardt, S., Kraenkel, A., Blaesche, J., Petzold, A., Kesavan, G., Lange, C., Brand, M., Detours, V., Costagliola, S., Singh, S. P.. 2020-01-14. Single-cell transcriptome analysis reveals cell-cell communication and thyrocyte diversity in the zebrafish thyroid gland. https://doi.org/10.1101/2020.01.13.891630

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