earlier studies using colchicine ( l. g. tilney and j. r. gibbins , 1969 , j. cell sci . 5 , 195-210 ) had suggested that intact microtubules ( mts ) are necessary for archenteron elongation during the second phase of sea urchin gastrulation ( secondary invagination ) , presumably by allowing secondary mesenchyme cells ( smcs ) to extend their long filopodial processes .
C0007634
cell
C0600315
filopodial