Lysosomal alpha-mannosidase (EC 3.2.1.24) is a major exoglycosidase in the glycoprotein degradation pathway. A deficiency of this enzyme causes the lysosomal storage disease, alpha-mannosidosis, which has been described in humans, cattle, domestic cats and guinea pigs. Recently, great progress has been made in studying the enzyme and its deficiency. This includes cloning of the gene encoding the enzyme, characterization of mutations related to the disease, establishment of valuable animal models, and encouraging results from bone marrow transplantation experiments.
Animal ; Cats ; Cattle ; Cloning, Molecular ; Disease Models, Animal ; Guinea Pigs ; Human ; Lysosomes/*enzymology ; Mannosidases/*deficiency/*genetics/metabolism ; Mannosidosis/diagnosis/*etiology/*therapy ; Mutation ; Support, Non-U.S. Gov't ; Support, U.S. Gov't, P.H.S. ; Transcription, Genetic

Lysosomal alpha-mannosidase (EC 3.2.1.24) is an exoglycosidase in the glycoprotein degradation pathway and is encoded by a 3.0 kb cDNA. A 2.3 kb cDNA from a minor species of HeLa cell mRNA was discovered by RT-PCR cloning. Southern blotting and PCR analysis of the HeLa cell genomic DNA showed that the 2.3 kb message was encoded by the lysosomal alpha-mannosidase gene. Sequence comparison of the cDNA with the corresponding genomic DNA indicated that the 2.3 kb message was generated by an unusual intra-exonic joining event.
*Alternative Splicing ; Base Sequence ; DNA, Complementary/genetics ; Exons ; Hela Cells ; Human ; Lysosomes/*enzymology ; Mannosidases/*genetics ; Molecular Sequence Data ; RNA, Messenger/*genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Support, U.S. Gov't, P.H.S.