Two interphase cells with immunofluorescence labeling of actin filaments (purple), microtubules (yellow), and nuclei (green). This image won first place in the Nikon 2003 Small World photo competition...

Phase contrast image of PtK1 cell (marsupial kidney epithelial cell) injected with Pak1 inhibitory fragment (H83L), X-rhodamine tubulin, and expressing constitutively active Rac(Q61L). Microtubule dyn...

Phase contrast of a PtK1 cell (marsupial kidney epithelial cell) injected with Pak1 inhibitory fragment (H83L, 120 uM needle concentration) and X-rhodamine tubulin. Microtubules dynamics in these cell...

Microtubules in a Rac1(Q61L)-expressing PtK1 cell injected with Pak inhibitory fragment PBD/ID(H83L). Microtubules do not exhibit retrograde flow and undergo very little net growth. Epifluorescence i...

Actin dynamics in a Rac1(Q61L)-expressing PtK1 cell injected with Pak inhibitory fragment PBD/ID(H83L). Fast retrograde flow still occurs in the lamellipodium, but the width of the lamellipodium is re...

Differential interference microscopy (DIC) image of PtK1 cell (marsupial kidney epithelial cell expressing dominant-negative Rac1(T17N). Live cells were used to study microtubule dynamics using X-rhod...

Microtubules in a PtK1 cell injected with the Pak inhibitory fragment PBD/ID(H83L). Microtubules do not exhibit retrograde flow and undergo very little net growth. Epifluorescence image series were ac...

Actin dynamics in a Rac1(Q61L)-expressing PtK1 cell. Fast retrograde flow occurs in the lamellipodium and slow retrograde flow in the lamellum. The cell was microinjected with X-rhodamine-conjugated a...

Microtubules in a constitutively active Rac1(Q61L)-expressing PtK1 cell. Microtubules are subjected to continuous retrograde flow away from the cell edge, but many plus ends undergo net growth and rem...

Phase contrast image of a PTK-1 cell expressing constitutively active Rac1(Q61L). Live cells were visualized using X-rhodamine tubulin (injected at 1 mg/mL)and eGFP-Rac1(Q61L) (injected into the nucl...