Transforming growth factor-beta 1 specifically induce proteins involved in the myofibroblast contractile apparatus.
Transforming growth factor-beta(1) (TGF-beta(1)) induces alpha-smooth muscle actin (alpha-SMA) and collagen synthesis in fibroblast both in vivo and in vitro and plays a significant role in tissue repair and the development of fibrosis. During these processes the fibroblasts differentiate into activated fibroblasts (so called myofibroblasts), characterized by increased alpha-SMA expression. Because TGF-beta(1) is considered the main inducer of the myofibroblast phenotype and cytoskeletal changes accompany this differentiation, the main objective of this investigation was to study how TGF-beta(1) alters protein expression of cytoskeletal-associated proteins. Metabolic labeling of cell cultures by [(35)S]methionine, followed by protein separation on two-dimensional gel electrophoresis, displayed approximately 2500 proteins in the pI interval of 3-10. Treatment of TGF-beta(1) led to specific spot pattern changes that were identified by mass spectrometry and represent specific induction of several members of the contractile apparatus such as calgizzarin, cofilin, and profilin. These proteins have not previously been shown to be regulated by TGF-beta(1), and the functional role of these proteins is to participate in the depolymerization and stabilization of the microfilaments. These results show that TGF-beta(1) induces not only alpha-SMA but a whole set of actin-associated proteins that may contribute to the increased contractile properties of the myofibroblast. These proteins accompany the induced expression of alpha-SMA and may participate in the formation of stress fibers, cell contractility, and cell spreading characterizing the myofibroblasts phenotype.
Malmström
Johan
J
Department of Molecular Sciences, AstraZeneca R&D Lund, SE-221 87 Lund, Sweden.
Lindberg
Henrik
H
Lindberg
Claes
C
Bratt
Charlotte
C
Wieslander
Elisabet
E
Delander
Eva-Lena
EL
Särnstrand
Bengt
B
Burns
Jorge S
JS
Mose-Larsen
Peter
P
Fey
Stephen
S
Marko-Varga
György
G
D008841:Actin Cytoskeleton / Q000378:metabolism; D051339:Actin Depolymerizing Factors; D000199:Actins / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects* / Q000502:physiology; D002478:Cells, Cultured; D003285:Contractile Proteins / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D007554:Isotopes / Q000737:chemistry; D013058:Mass Spectrometry; D008840:Microfilament Proteins / Q000378:metabolism; D009130:Muscle, Smooth / Q000166:cytology / Q000378:metabolism*; D051304:Profilins; D009418:S100 Proteins / Q000378:metabolism; D016212:Transforming Growth Factor beta / Q000494:pharmacology*; D053773:Transforming Growth Factor beta1
D051339:Actin Depolymerizing Factors; D000199:Actins; D003285:Contractile Proteins; D007554:Isotopes; D008840:Microfilament Proteins; C495738:PFN1 protein, human; D051304:Profilins; D009418:S100 Proteins; C508960:TGFB1 protein, human; D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; C072337:S100A11 protein, human