RNA-seq of Isolated Chromaffin Cells Highlights the Role of Sex-Linked and Imprinted Genes in Adrenal Medulla Development

Abstract

Adrenal chromaffin cells and sympathetic neurons synthesize and release catecholamines, and both cell types are derived from neural crest precursors. However, they have different developmental histories, with sympathetic neurons derived directly from neural crest precursors while adrenal chromaffin cells arise from neural crest-derived cells that express Schwann cell markers. We have sought to identify the genes, including imprinted genes, which regulate the development of the two cell types in mice. We developed a method of separating the two cell types as early as E12.5, using differences in expression of enhanced yellow fluorescent protein driven from the tyrosine hydroxylase gene, and then used RNA sequencing to confirm the characteristic molecular signatures of the two cell types. We identified genes differentially expressed by adrenal chromaffin cells and sympathetic neurons. Deletion of a gene highly expressed by adrenal chromaffin cells, NIK-related kinase, a gene on the X-chromosome, results in reduced expression of adrenaline-synthesizing enzyme, phenyl-N-methyl transferase, by adrenal chromaffin cells and changes in cell cycle dynamics. Finally, many imprinted genes are up-regulated in chromaffin cells and may play key roles in their development.

Interplay between intrinsic reprogramming potential and microenvironment controls neuroblastoma cell plasticity and identity

“…We nevertheless disagree with their interpretation of cell phenotypes. We strongly believe that CARTPT and INSM1, used by Dong et al to define sympathoblast identity, rather witness a chromaffin-like phenotype, since they are co-expressed with DLK1 , CDKN1C , CHGA / CHGB , TH , DBH and SLC18A1 in our data 25–27,40–44 . Integration of our single-cell RNA-seq data from 14 PDX models revealed two distinct cell populations expressing either markers of chromaffin cells or markers of sympathoblasts.…”

“…We next assessed the heterogeneity of the human tumor cell populations and documented that most clusters were shared by all PDX models ( Table S4 ). Several populations could be defined according to the differential expression of specific genes: cycling cells marked by the expression of TOP2A, MKI67 and CDK1 (clusters 2 and 6), cells driven by a MYCN/ 2p amplicon signature (clusters 0-1-2-3-13), cells expressing chromaffin markers such as CDKN1C , SLC18A1 /VMAT1 25,26 and DLK1 27 (clusters 9-10-11) and cells with a sympathoblast-like identity such as TFAP2B 28 (cluster 7) ( Figures 6E, S3D-F and Table S4 ).…”

Single-cell atlas of developing murine adrenal gland reveals relation of Schwann cell precursor signature to neuroblastoma phenotype

“…Of note is Rgs5, the marker for the committed progenitor cluster. It is suggested to be involved in chromaffin differentiation, is negatively regulated by MYCN, and its genomic locus is reported to be affected in neuroblastoma ( 45 , 46 ). It therefore would be intriguing to investigate what occurs to cells with the committed progenitors gene program in MYCN mouse models.…”

Development of the Autonomic Nervous System: Clinical Implications

“…40,41,95 They then begin differentiating into chromaffin cells, with a subset turning on PNMT and expressing adrenalin. 96,97 Like sympathetic neurons, adrenal chromaffin development is dependent on BMP signaling, Phox2b, and Mash1/Ascl. 41,44,46 Neural crest-derived glial cells in the form of sustentacular cells are also present in the adrenal medulla and may act as stem-like cells.…”

“…These new data have promise to yield interesting insights into not only chromaffin cell development but also how dysregulation of this network can trigger chromaffin cell-derived cancers. 96…”