Carmen V. Melendez-Vasquez, .
Assistant
Professor
E-mail: melendez@genectr.hunter.cuny.edu
Education
BSc 1991 Universidad Central de Venezuela
MSc 1992 Instituto Venezolano de Investigaciones Cientificas
PhD 1996
Postdoc
1997
1998-2003 New
York University
Research Interest
Actomyosin Regulation and Mechanism of Myelin Formation
Myelin is a highly
specialized membrane, which wraps around nerve fibers in the peripheral (PNS)
and central (CNS) nervous systems. While the function of the myelin sheath in
facilitating the efficient and rapid propagation of nerve impulses has long
been known, the mechanisms of its formation have remained elusive. During nerve
development, Schwann cells in the PNS and oligodendrocytes (Fig.1) in the CNS
undergo a series of striking changes that ultimately lead to their maturation
into specialized glial cells able to wrap around nerve fibers, and make myelin.
Figure 1. An oligodendrocyte the myelinating glial cell
of the CNS in culture, stained for myelin basic protein (MBP, red) and myosin
light chain (green)
Very little is known
about the mechanisms behind these morphogenetic events, but they are likely to
involve a combination of structural cytoskeletal elements and force-generating
molecules driving the extension of the plasma membrane and its coordinated
movement around the axon. Candidate molecules to accomplish such roles are
actin and the actin-associated motor protein myosin II. Using an in vitro
co-culture system (Fig. 2) our laboratory is actively investigating the regulation
of molecular motors during myelination by Schwann cells and
oligodendrocytes.
Figure 2. Myelinating co-culture of
Schwann cells and DRG neurons. Myelin
shown in red (MBP) and axons in blue (neurofilament)
The overall goal of
our research is to provide novel insights into the mechanisms that regulate
myelin morphology and formation in the PNS and CNS. A basic understanding of
the molecular machinery of myelination should aid in the development of new
therapeutic strategies to promote remyelination in pathological conditions such
as multiple sclerosis.
Selected Publications
Zhang Y., Taveggia C., Melendez-Vasquez, CV., Einheber S., Raine C S.,
Salzer J L., Brosnan C F and Gareth R. John (2006)
Interleukin-11 potentiates oligodendrocyte survival and maturation, and myelin
formation J.Neurosci 26: 12174-12185
Melendez-Vasquez, C.V., Carey D., Zanazzi, G., Reizes, O., Maurel
P., Salzer J.L. (2005) Differential expression of proteoglycans at central and
peripheral Nodes of Ranvier Glia 52:301-308.
Melendez -Vasquez, C.V., Einheber S., Salzer J.L (2004)
John GR, Chen L, Rivieccio MA, Melendez-Vasquez CV, Hartley A, Brosnan
CF.(2004) Interleukin-1beta induces a reactive astroglial phenotype via deactivation
of the Rho GTPase-Rock axis. J Neurosci.
24: 2837-2845.
Melendez-Vasquez, C.V., Rios, J.C., Zanazzi, G., Lambert, S., Bretscher, A. & Salzer, J.
(2001) Nodes of Ranvier form in association with ERM (ezrin-radixin-moesin)-positive Schwann cell processes. Proc. Natl. Acad. Sci. 98:1235-1240
Rios, J.C.*, Melendez -Vasquez, C.V*., Einheber, S.,
Lustig,M., Grumet, M., Gollan, L., Peles, E., Hemperly, J.J. & Salzer, J.L.
(2000) Caspr and contactin co-localize in the paranodal and internodal membranes
of myelinated axons. J. Neuroscience 20: 8354-8364. (*equal contribution).