Tunicate and sponge phagocytes highly express CEBPα homologs. (A) Scatter plots of sponge archaeocytes with log₂ (TPM + 1) values. The x-axes indicate sponge CEBPα and CEBPγ. The y-axes indicate total expression levels of phagocytosis-related genes and PLA2G15 (CEBPα homologs were excluded from phagocytosis-related genes in these analyses). (B) Expression levels with log₂ (TPM + 1) values of CEBPα, CEBPγ, and phagocytosis-related genes in tunicate. Transcriptome data of phagocytes were examined by RNA-seq, and data of the other lineages were based on expressed sequence tag counts obtained from the Ghost Database (http://ghost.zool.kyoto-u.ac.jp/cgi-bin/gb2/gbrowse/kh/). (C) Blood cells of tunicate was aspirated by cardiac puncture. Collected blood cells were incubated with pHrodo beads and analyzed by flow cytometry. (D) Blood cells of tunicate were analyzed by flow cytometry based on their size, autofluorescence, and fluorescence of engulfed beads. (E) Normalized expression levels (Gapdh = 1) of CEBPα, CEBPγ, and PLA2G15 in various lineage blood cells of tunicate were evaluated by RT-qPCR. Data are mean ± standard error of the mean. ∗P < .05, ∗∗∗P < .001, ∗∗∗∗P < .0001.