+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Trafficking of lysosomal cathepsin B-green fluorescent protein to the surface of thyroid epithelial cells involves the endosomal/lysosomal compartment

, : Trafficking of lysosomal cathepsin B-green fluorescent protein to the surface of thyroid epithelial cells involves the endosomal/lysosomal compartment. Journal of Cell Science 115(Pt 24): 4877-4889

Cathepsin B, a lysosomal cysteine proteinase, is involved in limited proteolysis of thyroglobulin with thyroxine liberation at the apical surface of thyroid epithelial cells. To analyze the trafficking of lysosomal enzymes to extracellular locations of thyroid epithelial cells, we have expressed a chimeric protein consisting of rat cathepsin B and green fluorescent protein. Heterologous expression in CHO cells validated the integrity of the structural motifs of the chimeric protein for targeting to endocytic compartments. Homologous expression, colocalization and transport experiments with rat thyroid epithelial cell lines FRT or FRTL-5 demonstrated the correct sorting of the chimeric protein into the lumen of the endoplasmic reticulum, and its subsequent transport via the Golgi apparatus and the trans-Golgi network to endosomes and lysosomes. In addition, the chimeras were secreted as active enzymes from FRTL-5 cells in a thyroid-stimulating-hormone-dependent manner. Immunoprecipitation experiments after pulse-chase radiolabeling showed that secreted chimeras lacked the propeptide of cathepsin B. Thus, the results suggest that cathepsin B is first transported to endosomes/lysosomes from where its matured form is retrieved before being secreted, supporting the view that endosome/lysosome-derived cathepsin B contributes to the potential of extracellular proteolysis in the thyroid.


PMID: 12432075

DOI: 10.1242/jcs.00184

Other references

Buisseret-Delmas, C.B.tini, C., 1977: Anatomical identification of vestibulo olivary and cerebelloo olivary projection in the cat. Comptes rendus hebdomadaires des seances Serie D Sciences naturelles: 285 (7) 783-784

Fujita, T.; Gotohda, N.; Kato, Y.; Kinoshita, T.; Takahashi, S.; Konishi, M.; Daiko, H.; Nishimura, M.; Kuwata, T.; Ochiai, A.; Kinoshita, T., 2013: Clinicopathological features of stomach cancer with invasive micropapillary component. Invasive micropapillary carcinoma has been recognized as a rare disease entity with aggressive tumor behavior. However, few reports have described invasive micropapillary carcinoma in the gastrointestinal tract, particularly its involvement in gas...

Das, U.N., 2002: Insulin and inflammation: further evidence and discussion. Nutrition 18(6): 526-527

Davis C.P.; Mulcahy D.; Takeuchi A.; Savage D.C., 1972: Spirochetes and spiral shaped bacteria in normal rat ceca. Abstracts of the Annual Meeting of the American Society for Microbiology 72: 118

Petro, M.L.; Lancon, J.A., 2001: Occipital aneurysmal bone cyst. Pediatric Neurosurgery 34(1): 45-46

Ada, G.L.; Perry, B.T., 1954: The nucleic acid content of influenza virus. Australian Journal of Experimental Biology and Medical Science 32(4): 453-468

Duus R.E., 1988: Response class in the organization setting the effects of location specific feedback. Location-specific, publicly posted performance data were effective in improving and increasing interactions between staff and residents of an institutional residential program. The procedure used to provide the performance feedback to direct care...

Umemoto, T.; Hamada, N., 2003: Characterization of biologically active cell surface components of a periodontal pathogen. The roles of major and minor fimbriae of Porphyromonas gingivalis. Background: We previously reported that the presence of 2 different types of fimbriae expressed on the cell surface of Porphyromonas gingivalis ATCC 33277. The initial event in most infectious diseases involves adhesion of pathogens to host tissue...

Key, J.D.; Mann, R.J., 1985: Caricatures in Vanity Fair. Medical Heritage 1(1): 75-78

McCarthy, T.J.; Mapp, R.K., 1970: A comparative investigation of methods used to estimate aloin and related compounds in Aloes. Although glucagon exerts positive inotropic effects in patients with no or mild impairment of cardiac function, similar effects are not consistently observed in patients with chronic heart failure. Accordingly, the inotropic effects of glucagon on...