Hapln1b interacts with kitlgb to maintain kitlgb-kitb interactions in the AGM. (A) ISH expression pattern of runx1 in control morphants, kitlga mRNA–injected embryos, kitlgb mRNA–injected embryos, hapln1b morphants, embryos injected with both hapln1b MO and kitlga mRNA, and embryos injected with both hapln1b MO and kitlgb mRNA. (A′) Analysis of runx1 expression. All results are compared with control MO. Data were analyzed by Fisher’s exact test using R. Control (ctl) MO vs +kitlga, P = .05826; NI vs +kitlgb, P = .7939; NI vs +hapln1b, P < .0001; NI vs +hapln1b+kitlga, P < .0001; and NI vs +hapln1b+kitgb: P < .0001. (B) ISH expression of cmyb in NI control embryos, hapln1b mRNA–injected embryos, kitlgb mRNA–injected embryos, and embryos injected with both hapln1b and kitlgb. (B′) analysis of cmyb expression. All analysis is compared with the NI control. Data were analyzed by Fisher’s exact test using R. NI vs +kitlga, P = .8373; NI vs +kitlgb, P = .99; NI vs +hapln1b, P = .0051; NI vs +hapln1b+kitlga, P = .036; and NI vs +hapln1b+kitgb, P = .8617. h1b, hapln1b; ka, kitlga; Kb, kitlgb. (C) Electrostatic potential of KITL, kiltga and kitlgb at biological pH. Blue, positive charge; white, neutral charge; red, negative charge. NI, non-injected.