Fig 6

(A) Top: single-cell sequencing of METRN in human embryonic hearts [64]. METRN is most up-regulated in the neural crest cluster (purple dotted box). Scale bar denotes relative gene expression. Bottom: spatiotemporal sequencing [64] of METRN in human embryonic hearts. Dot color denotes relative transcript expression. (B) Single-cell sequencing [65] from the neuronal cluster of human adult hearts. Scale bar denotes relative gene expression. (C) Coexpression of METRN and astroglial genes from human adult single-cell sequencing data [65]. Axes denote relative gene expression. (D) Confocal 20 μm z-projection of 6 dpf zebrafish animals with metrn RNAScope. Metrn localizes to the retina and the brain. (E) Confocal z-sections of metrn RNAScope 5 dpf Tg(sox10:nls-eos) zebrafish embryos. Metrn⁺ puncta (white arrowhead) localize to Eos⁺ cells. (F) Quantification of metrn⁺ puncta per cell in the heart. (G) Quantification of the number of metrn mRNA puncta in the heart at 2, 4, and 6 dpf. (H) Quantification of locational development of metrn mRNA puncta in the heart at 2, 4, and 6 dpf. (I) Confocal z-sections of metrn mRNA puncta (white arrowheads) across location and time in the heart (white dotted outline). Data are represented as mean ± SEM. Scale bar equals 10 μm. Statistics summarized in S1 Table. See S1 Data for raw data. dpf, days postfertilization; OT, outflow tract; P, pupil.