Accurate axon guidance is absolutely essential
to the development and function of the nervous
system, and abnormalities in neural connectivity
are associated with a multitude of neuro-
developmental disorders. 

Formation of neural connections occurs in the
embryo and depends upon precise navigation
by the neuronal growth cone.  The growth cone
is the motile structure at the tip of the growing
axon that navigates through the embryonic
terrain to find its specific target.  Motility and
steering of the growth cone occur through
dynamic regulation of its cytoskeleton.  One of
the fundamental problems in understanding
axon pathfinding is to determine how guidance
cue signaling pathways are integrated to coordinate
cytoskeletal dynamics.

The long-term goal of my lab is to understand
how cytoskeletal coordination occurs in the
embryonic growth cone.  Specifically, we focus
on the regulation of the plus-ends of microtubules
(MTs), which play a key role in growth cone steering.
An important feature of MT plus-ends is the presence
of a conserved set of proteins called 'plus-end tracking
proteins' (+TIPs) that localize to the plus-ends and
regulate their behavior.  Evidence suggests that +TIPs
act in response to upstream guidance cues by
coordinating the downstream MT response. 
Our research utilizes high-resolution live imaging
and computational analysis of cytoskeletal
behavior in cultured Xenopus laevis growth cones
to answer the question of how +TIPs interact and
function within the growth cone.

+TIP EB1 fused to GFP in live
Xenopus laevis
growth cone

EB1-red and CLASP-green

+TIP EB1 (in green) tracks along the growing ends of microtubules (in red) in a live Xenopus laevis growth cone
The Lowery Lab
Biology Department at Boston College
Funding for this research has been provided by
 Boston College, American Cancer Society, March of Dimes,
 the National Institute of Mental Health and the National Institute of Dental and Craniofacial Research.