Cell-specific localization of the sulphydryl oxidase QSOX in rat peripheral tissues.
Rat quiescin/sulphydryl oxidase (rQSOX) introduces disulphide bridges into peptides and proteins with the reduction of molecular oxygen to hydrogen peroxide. Its occurrence has been previously highlighted in a wide range of organs by reverse transcription-polymerase chain reaction (RT-PCR) and Northern blot analyses, methods that have provided information concerning its expression in whole organs but that do not reveal the cell types expressing this enzyme. In this report, in addition to RT-PCR and Western blot experiments, the cell-specific localization of rQSOX has been investigated in a wide range of male and female adult rat tissues by using in situ hybridization and immunohistochemistry. Labelling was detected in most organs and systems including the immune, endocrine and reproductive systems, the respiratory, digestive and urinary tracts and the skin. No labelling was observed in the heart, blood vessel endothelium, liver or smooth and skeletal muscles. rQSOX expression was mainly localized in epithelial cells specialized in secretion, strengthening the hypothesis that QSOX enzymes play an important role in the mechanism of secretion, notably in the folding of secreted proteins. The intracellular patterns of immunolabelling indicate that the protein usually follows the secretory pathway, which is in accordance with its secreted nature and its presumed involvement in the elaboration of the extracellular matrix. In seminiferous tubules, where a high level of expression was noticed, QSOX might play an important physiological role in sperm function and serve as a marker for the diagnosis of male infertility.
Tury
Anna
A
Laboratoire d'Histologie, E.A. 3922 Estrogènes, Expression Génique et Pathologies du Système Nerveux Central, IFR INSERM 133, Faculté de Médecine et de Pharmacie, Université de Franche-Comté, 19 Rue Ambroise Paré, 25041, Besançon, France.
Mairet-Coello
Georges
G
Esnard-Fève
Annick
A
Benayoun
Béatrice
B
Risold
Pierre-Yves
PY
Griffond
Bernadette
B
Fellmann
Dominique
D
D000818:Animals; D005260:Female; D005786:Gene Expression Regulation; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008297:Male; D051379:Mice; D010088:Oxidoreductases / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012671:Seminiferous Tubules / Q000378:metabolism*; D012680:Sensitivity and Specificity; D014018:Tissue Distribution; D050862:Oxidoreductases Acting on Sulfur Group Donors
D010088:Oxidoreductases; D050862:Oxidoreductases Acting on Sulfur Group Donors