Intersectin 2 nucleotide exchange factor regulates Cdc42 activity during Xenopus early development

► ITSN2 long isoform (ITSN2-L) is involved in Xenopus early embryonic development. ► Embryos expressing the C-terminal extension of ITSN2-L demonstrated gastrulation arrest. ► The DH-PH tandem of ITSN2-L colocalized with actin and affected actin polymerization in embryos. ► Developmental defects induced by microinjection of DH-PH mRNA depended on the activity of Cdc42.