Molecular cloning and expression of Ena/Vasp-like (Evl) during Xenopus development.

Ena/VASP proteins are actin-binding proteins implicated in the regulation of axon guidance, platelet aggregation, cell motility, and cell adhesion. The vertebrate Ena/VASP family is comprised of three genes: Ena (Enabled), VASP (Vasodilator Stimulated Phosphoprotein), and Evl (Ena/VASP-Like). We have cloned and characterized cDNAs encoding three alternatively spliced isoforms of Xenopus laevis Evl, designated Xevl, Xevl-I and Xevl-H. Analysis of the temporal expression of Xevl, Xevl-I and Xevl-H demonstrates that transcripts for each isoform are first detectable at low levels at stage 18, show increased abundance by stage 23, and persist throughout the remainder of embryogenesis. In situ hybridization analyses using a probe that detects all three Xevl isoforms or a probe that specifically detects the Xevl-H isoform revealed expression in the cement gland, brain, neural tube, myotome, and neural placodes, including the otic, lateral line, and olfactory placodes. These results suggest roles for Xevl in regulating actin dynamics and cell adhesion in neural and mesodermal tissues during later stages of Xenopus development.