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Identification of Nucleolar Factors During HIV-1 Replication Through Rev Immunoprecipitation and Mass Spectrometry
Published on: June 26, 2019
Identification of a human cDNA sequence which encodes a novel membrane-associated protein containing a zinc
Ying-Chun Bao1, Hiromichi Tsuruga, Momoki Hirai
1Division of Cell Therapy, Division of Hematopoietic Factors, The Advanced Clinical Research Center, The Institute of Medical Science, University of Tokyo, 6-1 Shirokanedai 4-chome, Minato-ku, Tokyo 108-8639, Japan.
Abstract:
We report the cloning and characterization of a human cDNA predicted to encode a novel hydrophobic protein containing four transmembrane domains and a zinc metalloprotease motif, HEXXH, between the third and fourth transmembrane domains, and have named the molecule metalloprotease-related protein-1 (MPRP-1). The MPRP-1 gene was localized to chromosome 1-p32.3 by radiation hybrid mapping, and Northern blot analysis revealed expression in many organs, with strong expression in the heart, skeletal muscle, kidney and liver. Immunohistochemical analyisis showed that MPRP-1 was localized in the endoplasmic reticulum (ER), and not in the Golgi compartment. Fragments of DNA encoding a segment homologous to the HEXXH motif of MPRP-1 are widely found in bacteria, yeast, plants, and animals. These results suggest that the MPRP-1 may have highly conserved functions, such as in intracellular proteolytic processing in the ER.
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