WISH assays. (A-D) WISH assays of mpo and gata1 at 22 hpf. Knock-down of SUMO paralogs by MOs results in an increased expression of the granulocytic-specific marker mpo (A-B) and a decreased expression of the erythroid-specific marker gata1 (C-D). Blue arrows indicate mpo⁺ cells and red arrows indicate gata1⁺ cells. Note that mpo expression in the A-LPM does not show any significant change (square bracket in panels A and B). (E-H) WISH assays of hbae1 and hbae3 at 48 hpf. Expression of hemoglobin hbae1 and hbae3 decreases in SUMO-deficient embryos (F and H) compared with those of WT (E and G). (I-L) Two-color WISH analysis of gata1 (red) and mpo (black) at 22 hpf. Panels K and L are highly magnified images of corresponding boxed regions from I and J, respectively. (M-P) Whereas zebrafish SUMO2 mRNA specifically reverses the SUMO-deficient phenotypes (M and O), SUMO2 ΔGG mRNA becomes ineffective (N and P). D.r indicates Danio rerio.