title: Smooth muscle actin and myosin expression in cultured airway smooth muscle cells.
abstract: In this study, the expression of smooth muscle actin and myosin was examined in cultures of rat tracheal smooth muscle cells. Protein and mRNA analyses demonstrated that these cells express alpha- and gamma-smooth muscle actin and smooth muscle myosin and nonmuscle myosin-B heavy chains. The expression of the smooth muscle specific actin and myosin isoforms was regulated in the same direction when growth conditions were changed. Thus, at confluency in 1 or 10% serum-containing medium as well as for low-density cells (50-60% confluent) deprived of serum, the expression of the smooth muscle forms of actin and myosin was relatively high. Conversely, in rapidly proliferating cultures at low density in 10% serum, smooth muscle contractile protein expression was low. The expression of nonmuscle myosin-B mRNA and protein was more stable and was upregulated only to a small degree in growing cells. Our results provide new insight into the molecular basis of differentiation and contractile function in airway smooth muscle cells.
authors.affiliation: Department of Molecular Physiology, University of Vermont, Burlington 05405, USA.
authors.forename: J Z
authors.initials: JZ
authors.lastname: Wong
authors.forename: J
authors.initials: J
authors.lastname: Woodcock-Mitchell
authors.forename: J
authors.initials: J
authors.lastname: Mitchell
authors.forename: P
authors.initials: P
authors.lastname: Rippetoe
authors.forename: S
authors.initials: S
authors.lastname: White
authors.forename: M
authors.initials: M
authors.lastname: Absher
authors.forename: L
authors.initials: L
authors.lastname: Baldor
authors.forename: J
authors.initials: J
authors.lastname: Evans
authors.forename: K M
authors.initials: KM
authors.lastname: McHugh
authors.forename: R B
authors.initials: RB
authors.lastname: Low
mesh_terms: D000199:Actins / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D015152:Blotting, Northern; D002478:Cells, Cultured; D003285:Contractile Proteins / Q000378:metabolism; D003598:Cytoskeletal Proteins / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D007150:Immunohistochemistry; D008297:Male; D009130:Muscle, Smooth / Q000166:cytology / Q000378:metabolism*; D009218:Myosins / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D014132:Trachea / Q000166:cytology / Q000378:metabolism*
chemical_list: D000199:Actins; D003285:Contractile Proteins; D003598:Cytoskeletal Proteins; D012333:RNA, Messenger; D009218:Myosins