Abstract
Previous studies suggest tissue inhibitor of metalloproteinase-2 (TIMP-2) plays a role in neural crest (NC) pathway choice. TIMP-2 expression by cranial NC correlates positively with taking the dorsolateral pathway. However in the trunk where TIMP-2 is not expressed in NC cells, NC cells initially take the ventromedial pathway. Here, we tested whether miss-expression of TIMP-2 in trunk NC cells redirects NC cell migration into the dorsolateral pathway. A bicistronic vector driving both TIMP-2 and enhanced green fluorescent protein (EGFP) expression or one lacking the TIMP-2 sequence was introduced by in ovo electroporation into NC precursors at the future wing bud axial level. Embryos were then reincubated for 24 hours and those exhibiting EGFP expression were fixed, immunostained as whole mounts for EGFP and NC cells (HNK-1 antibody), embedded, and sectioned. Pathway choice of trunk NC cells was scored as either taking the ventromedial, dorsolateral, or both. Our results show that miss-expressing TIMP-2 in early trunk NC cells significantly increases dorsolateral migration.