Hippocampal neuron cultured for 3 weeks and stained for DNA in the nucleus (blue), the microtubule- associated protein MAP2 (green), and actin filaments (red). In mature neurons, MAP2 is present only in cell  bodies and dendrites and absent from axons. Actin filaments are present thoughout the neuron, including axons, but are especially enriched in dendritc spines, which appear as bright red dots along the dendrites. Hippocampal neuron cultured for 24 hours and stained for DNA in the nucleus (blue), microtubules (green), and actin filaments (red). Note the high concentration of actin in the growth cones at the tips of emerging neurites in this immature neuron.

click to start movie (AVI - Microsoft MPEG-4 format)

click to start movie (AVI  - Microsoft MPEG-4 format)
Hippocampal neuron expressing GFP-Actin.   Neuro2a neuroblastoma cells transfected with CFP-Actin (red) and YFP-MAP2c (green) were imaged during the formation of a process. Note the gradual alignment of MAP2c-decorated microtubules and the protrusion of the actin-rich growth cone. Actin in the growth cone is highly dynamic undergoing rapid retrograde flow.
Spherical aggregate of differentiating P19 cells, stained for MAP2 (red), F-actin (green) and nuclei (blue). 
Shelley Halpain, Ph.D.
Associate Professor, Department of Cell Biology
The Scripps Research Institute and Institute for Childhood and Neglected Diseases 
10550 North Torrey Pines Road, ICND210E
La Jolla, CA 92037
Fax: (858) 784-9860
e-mail: shelley@scripps.edu
 

All rights reserved. ©2003 ShelleyHalpain.