Clara secretory protein

Zhang L, Whitsett JA, Stripp BR (1997) Regulation of Clara cell secretory protein gene transcription by thyroid transcription factor-1. Biochim Biophys Acta 1350(3) 359-367... 

Stripp BR, Lund J, Mango GW, etal. 1996. Clara cell secretory protein a determinant of PCB bioaccumulation in mammals. Am J Physiol 27LL656-L664. 

Vimentin is a 58-kD intermediate filament found predominantly in mesenchymal cells. However, vimentin is expressed in most spindle cell carcinomas and is reported by some to be expressed in a relatively high percentage of pulmonary adenocarcinomas. Thyroid transcription factor-1 (TTF-1), a 38- to 40-kD transcription factor member of the NKx2 family of home-odomain transcription factors, is expressed in thyroid and pulmonary epithelial cells. 49 TTF-1 binds to and activates the promoters for Clara cell secretory protein and surfactant proteins A, B, and As reported... 

Hacked BP, Gitlm JD Cell-specihc expression of a Clara cell secretory protein-human growth hormone gene in the bronchiolar epithelium of transgenic mice Proc Natl Acad Sci USA 1992, 89 9079-9083... 

After an intratracheal instillation of benzo[a]py-rene (1 mg dissolved in 50 /tl tricaprylin), the Clara cell secretory protein dominant-negative mutant form of p53 transgenic mice was more susceptible... 

The prominent organelle in the cytoplasm of Clara cells from both wild-type strain 129 and Clara cell secretory protein -/- 129 mice is the smooth endoplasmic reticulum, which occupies about 20% of the cell cytoplasm (Strife et al. 2002). Despite the similarities in abundance there were two aspects of the smooth endoplasmic reticulum that differed markedly between both genotypes of mice. First, electron-dense material that was abundant within the lumen of smooth endoplasmic reticulum of Clara cells from wild-type mice was not as evident within the lumen of smooth endoplasmic reticulum of Clara cells from Clara cell secretory protein -/-129 mice. Second, Clara cells from Clara cell secretory protein -/- 129 mice were unique in that they possessed large concentric whorls of endoplasmic reticulum located within the apical portion of the cell. Membrane-bound inclusions, which appeared to he surrounded by at least one layer of endoplasmic reticulum, were found at the centre of these whorls and contained material of varying electron density and compaction. Some of these inclusions had the characteristics of mitochondria based on the presence of crista-like membrane inclusion. 

Clara cell secretory protein, known by a number of other names including urinary protein 1, uteroglo-bulin (Peri et al. 1995, Mukherjee et al. 1999), PCB-binding protein, and Clara cell 10 kDa protein (Mantile et al. 1993, Dodge et al. 1994, Singh and Katyal 1997) has been described as a multifunctional protein . 

Ozone (1.010.1 ppm) transiently increased IL-6 mRNA showing peak levels at 4 h of ozone exposure in both wild-type and Clara cell secretory protein -/- mice (Mango et al. 1998). Differential metallo-thionein and IL-6 mRNA expression demonstrated increased ozone-induced oxidative stress associated with Clara cell secretory protein deficiency. 

While bronchiolar epithelium in normal C57BL/ 6 mice contains cells that express high levels Clara cell 10 kDa secretory protein and CYP2F, and exhibit the characteristic pattern of naphthalene injury and repair, Clara cell 10 kDa secretory protein and CYP2F expression was less abundant in transgenic C57BL/g yS T cell knock-out mice (Van Winkle et al. 1997). In knock-out mice 1 to 2 days post injury, injury was not uniform within the terminal bronchiole. Distal ends of the bronchiole contained Clara cell 10 kDa secretory protein positive epithehal cells and were not injured. 

Hong KU, Reynolds SD, Giangreco A, Hurley CM, Stripp BR. Clara cell secretory protein-expressing cells of the airway neuroepithelial body microenvironment include a label-retaining subset and are critical for epithelial renewal after progenitor cell depletion. Am J Respir Cell Mol Biol 2001 24 671-681. 

In primates, including man, the Clara cell has the features of a serous secretory cell that produces a protein-rich secretion. 

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