The extracellular matrix (ECM) of the adult brain is unique in its molecular composition, and while abundant in various types of proteoglycans, it lacks most common ECM proteins, such as collagens and fibronectin, in its parenchyma. Brevican, a member of the lectican family proteoglycans, is one of the most abundant proteoglycans in the adult brain and is localized mainly in perineuronal nets (PNN), a major form of the ECM in the adult brain surrounding neuronal cell bodies. Dr. Yamaguchi's studies revealed that brevican (and also other lecticans) binds tenascin-R, a nervous system-specific ECM protein, through its C-type lectin domain by protein-protein interactions. Interestingly, both tenascin-R and hyaluronan, another ligand for lecticans, have been identified in PNN. These findings have led to the proposal that hyaluronan, lectican, and tenascin-R form a ternary complex (""""""""HLT complex"""""""") in PNN, and that such a ternary complex constitutes the core of the adult brain ECM. This HLT model has substantial physiological and pathophysiological implications. First, it has been suggested that the PNN is functionally involved in the process of synapse elimination which underlies developmental changes of neural plasticity. Because both lecticans and tenascin-R are known to act as repulsive substrates, it is hypothesized that the HLT complex serves as a super-repulsive substrate that prevents excessive synapse formation on mature neurons. Second, the brain ECM has been implicated in the invasive behavior of glioma cells. As the major components of the brain ECM, the HLT matrix may be an important factor that defines the invasiveness of glioma cells. The main goal of this proposal is to determine the roles of the HLT matrix in adult neural function and in glioma invasion, thereby forming a new paradigm for the physiological and pathophysiological roles of the brain ECM. Toward this goal: 1) the ternary interaction of hyaluronan, brevican, and tenascin-R will be characterized; 2) the effect of the brevican-tenascin-R complex on neurite outgrowth and growth cone responses will be determined; 3) the roles of the HLT matrix on synapse formation and elimination in vivo will be identified using Purkinje cell-targeted transgene expression; and 4) the role of hyaluronan in glioma invasion will be determined by genetic manipulation of hyaluronan synthesis using the hyaluronan synthase Has2.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
5R01NS032717-07
Application #
6393659
Study Section
Pathobiochemistry Study Section (PBC)
Program Officer
Mamounas, Laura
Project Start
1995-06-01
Project End
2003-05-31
Budget Start
2001-06-01
Budget End
2002-05-31
Support Year
7
Fiscal Year
2001
Total Cost
$353,828
Indirect Cost
Name
Sanford-Burnham Medical Research Institute
Department
Type
DUNS #
009214214
City
La Jolla
State
CA
Country
United States
Zip Code
92037
Kadoya, Kuniko; Fukushi, Jun-Ichi; Matsumoto, Yoshihiro et al. (2008) NG2 proteoglycan expression in mouse skin: altered postnatal skin development in the NG2 null mouse. J Histochem Cytochem 56:295-303
Fukushi, Jun-ichi; Inatani, Masaru; Yamaguchi, Yu et al. (2003) Expression of NG2 proteoglycan during endochondral and intramembranous ossification. Dev Dyn 228:143-8
Srikrishna, Geetha; Huttunen, Henri J; Johansson, Lena et al. (2002) N -Glycans on the receptor for advanced glycation end products influence amphoterin binding and neurite outgrowth. J Neurochem 80:998-1008
Jones, Leonard L; Yamaguchi, Yu; Stallcup, William B et al. (2002) NG2 is a major chondroitin sulfate proteoglycan produced after spinal cord injury and is expressed by macrophages and oligodendrocyte progenitors. J Neurosci 22:2792-803
Ogawa, T; Hagihara, K; Suzuki, M et al. (2001) Brevican in the developing hippocampal fimbria: differential expression in myelinating oligodendrocytes and adult astrocytes suggests a dual role for brevican in central nervous system fiber tract development. J Comp Neurol 432:285-95
Miura, R; Ethell, I M; Yamaguchi, Y (2001) Carbohydrate-protein interactions between HNK-1-reactive sulfoglucuronyl glycolipids and the proteoglycan lectin domain mediate neuronal cell adhesion and neurite outgrowth. J Neurochem 76:413-24
Yamaguchi, Y (2000) Lecticans: organizers of the brain extracellular matrix. Cell Mol Life Sci 57:276-89
Hagihara, K; Miura, R; Kosaki, R et al. (1999) Immunohistochemical evidence for the brevican-tenascin-R interaction: colocalization in perineuronal nets suggests a physiological role for the interaction in the adult rat brain. J Comp Neurol 410:256-64
Miura, R; Aspberg, A; Ethell, I M et al. (1999) The proteoglycan lectin domain binds sulfated cell surface glycolipids and promotes cell adhesion. J Biol Chem 274:11431-8
Kosaki, R; Watanabe, K; Yamaguchi, Y (1999) Overproduction of hyaluronan by expression of the hyaluronan synthase Has2 enhances anchorage-independent growth and tumorigenicity. Cancer Res 59:1141-5

Showing the most recent 10 out of 15 publications