Localization of smoothelin in avian smooth muscle and identification of a vascular-specific isoform

AbstractSmoothelin is a smooth muscle-specific protein of minor abundance first identified via a monoclonal antibody obtained using an avian gizzard extract as antigen. Dual labelling of ultrathin sections with antibodies to smoothelin together with antibodies to other smooth muscle proteins showed that smoothelin was co-distributed with filamin and desmin in the cytoskeleton domain of the smooth muscle cell. From the finding that smoothelin, unlike desmin, was readily extracted by Triton X-100 as well as under conditions that solubilized myosin, β-actin and filamin, we conclude that smoothelin is most likely associated with the actin cytoskeleton. Western blot analysis of gizzard smooth muscle tissue revealed an immunoreactive protein band with an apparent molecular weight of 59 kDa that separated into 3–4 isolated variants, while avian vascular muscle showed a polypeptide band of 95 kDa. These results point to the presence of specific isoforms in visceral and vascular smooth muscles. The 59 kDa isoform was shown to be distinct from the 60 kDa filamin-binding protein, described by Maekawa and Sakai (FEBS Lett. 221, 68–72, 1987). As compared to other smooth muscle markers, such as calponin and SM22, smoothelin appeared very late during differentiation in the chick gizzard, on about the 18th embryonic day

Responses of the PAS-positive pars intermedia cells in the cichlid fish Sarotherodon mossambicus to ambient calcium and background adaptation

Contains fulltext : 10734.pdf (publisher's version ) (Open Access

Physiological and biochemical aspects of the teleostean pars intermedia

Contains fulltext : mmubn000001_026847671.pdf (publisher's version ) (Open Access)Promotores : S. Wendelaar Bonga en A. van Overbeeke131 p

Isolation of the biosynthetic products of the PAS positive pars-intermedia cells in the cichlid teleost Sarotherodon mossambicus

Contains fulltext : 10730.pdf (publisher's version ) (Open Access

Biosynthesis of melanotropins and endorphins by the lead haematoxylin positive cells in the pars intermedia of the cichlid teleost Sarotherodon mossambicus

Contains fulltext : 10735.pdf (publisher's version ) (Open Access

Environmental control of prolactin synthesis in the teleost fish Oreochromis (formerly sarotherodon) mossambicus

Contains fulltext : 10763.pdf (publisher's version ) (Open Access

Regulation and characteristics of vascular smooth muscle cell phenotypic diversity

Vascular smooth muscle cells can perform both contractile and synthetic functions, which are associated with and characterised by changes in morphology, proliferation and migration rates, and the expression of different marker proteins. The resulting phenotypic diversity of smooth muscle cells appears to be a function of innate genetic programmes and environmental cues, which include biochemical factors, extracellular matrix components, and physical factors such as stretch and shear stress. Because of the diversity among smooth muscle cells, blood vessels attain the flexibility that is necessary to perform efficiently under different physiological and pathological conditions. In this review, we discuss recent literature demonstrating the extent and nature of smooth muscle cell diversity in the vascular wall and address the factors that affect smooth muscle cell phenotype. (Neth Heart J 2007;15:100-8.17612668

Smoothelin in vascular smooth muscle cells

Smoothelin-A and -B have only been found in fully differentiated contractile smooth muscle cells. They are increasingly used to monitor the smooth muscle cell differentiation process to a contractile or synthetic phenotype. Vascular-specific smoothelin-B is the first smooth muscle cell marker that disappears when vascular tissues are compromised, for example, in atherosclerosis or restenosis. Recently obtained data show that smoothelin deficiency results in a considerable loss of contractile potential and hence in impaired smooth muscle function and suggest that smoothelins are part of the contractile apparatus