Transcriptome-based systematic identification of extracellular matrix proteins.
Extracellular matrix (ECM), which provides critical scaffolds for all adhesive cells, regulates proliferation, differentiation, and apoptosis. Different cell types employ customized ECMs, which are thought to play important roles in the generation of so-called niches that contribute to cell-specific functions. The molecular entities of these customized ECMs, however, have not been elucidated. Here, we describe a strategy for transcriptome-wide identification of ECM proteins based on computational screening of >60,000 full-length mouse cDNAs for secreted proteins, followed by in vitro functional assays. These assays screened the candidate proteins for ECM-assembling activities, interactions with other ECM molecules, modifications with glycosaminoglycans, and cell-adhesive activities, and were then complemented with immunohistochemical analysis. We identified 16 ECM proteins, of which seven were localized in basement membrane (BM) zones. The identification of these previously unknown BM proteins allowed us to construct a body map of BM proteins, which represents the comprehensive immunohistochemistry-based expression profiles of the tissue-specific customization of BMs.
Manabe
Ri-ichiroh
R
Sekiguchi Biomatrix Signaling Project, Exploratory Research for Advanced Technology, Japan Science and Technology Agency, c/o Aichi Medical University, Nagakute, Aichi 480-1195, Japan.
Tsutsui
Ko
K
Yamada
Tomiko
T
Kimura
Mina
M
Nakano
Itsuko
I
Shimono
Chisei
C
Sanzen
Noriko
N
Furutani
Yutaka
Y
Fukuda
Tomohiko
T
Oguri
Yasuko
Y
Shimamoto
Keiko
K
Kiyozumi
Daiji
D
Sato
Yuya
Y
Sado
Yoshikazu
Y
Senoo
Haruki
H
Yamashina
Shohei
S
Fukuda
Shiro
S
Kawai
Jun
J
Sugiura
Nobuo
N
Kimata
Koji
K
Hayashizaki
Yoshihide
Y
Sekiguchi
Kiyotoshi
K