Maturation and pro-peptide cleavage of beta-secretase.
Amyloid beta-peptide is generated by two sequential proteolytic cleavages mediated by beta-secretase (BACE) and gamma-secretase. BACE was recently identified as a membrane-associated aspartyl protease. We have now analyzed the maturation and pro-peptide cleavage of BACE. Pulse-chase experiments revealed that BACE is post-translationally modified during transport to the cell surface, which can be monitored by a significant increase in the molecular mass. The increase in molecular mass is caused by complex N-glycosylation. Treatment with tunicamycin and N-glycosidase F led to a BACE derivative with a molecular weight corresponding to an unmodified version. In contrast, the mature form of BACE was resistant to endoglycosidase H treatment. The cytoplasmic tail of BACE was required for efficient maturation and trafficking through the Golgi; a BACE variant lacking the cytoplasmic tail undergoes inefficient maturation. In contrast a soluble BACE variant that does not contain a membrane anchor matured more rapidly than full-length BACE. Pro-BACE was predominantly located within the endoplasmic reticulum. Pro-peptide cleavage occurred immediately before full maturation and trafficking through the Golgi.
Capell
A
A
Adolf Butenandt-Institute, Department of Biochemistry, Laboratory for Alzheimer's Disease Research, Ludwig-Maximilians-University, 80336 Munich, Germany.
Steiner
H
H
Willem
M
M
Kaiser
H
H
Meyer
C
C
Walter
J
J
Lammich
S
S
Multhaup
G
G
Haass
C
C
D000581:Amidohydrolases / Q000494:pharmacology; D053829:Amyloid Precursor Protein Secretases; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D016282:Aspartic Acid Endopeptidases / Q000737:chemistry* / Q000378:metabolism*; D001692:Biological Transport; D001921:Brain / Q000378:metabolism; D002460:Cell Line; D002462:Cell Membrane / Q000378:metabolism; D003001:Cloning, Molecular; D017077:Culture Media, Conditioned; D018076:DNA, Complementary / Q000378:metabolism; D010450:Endopeptidases; D004721:Endoplasmic Reticulum / Q000378:metabolism; D015723:Gene Library; D006026:Glycoside Hydrolases / Q000494:pharmacology; D006031:Glycosylation; D006056:Golgi Apparatus / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008856:Microscopy, Fluorescence; D016297:Mutagenesis, Site-Directed; D043524:Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase; D010455:Peptides / Q000378:metabolism*; D011233:Precipitin Tests; D017434:Protein Structure, Tertiary; D013997:Time Factors; D014162:Transfection; D014415:Tunicamycin / Q000494:pharmacology
D000900:Anti-Bacterial Agents; D017077:Culture Media, Conditioned; D018076:DNA, Complementary; D010455:Peptides; D014415:Tunicamycin; D006026:Glycoside Hydrolases; D053829:Amyloid Precursor Protein Secretases; D010450:Endopeptidases; D016282:Aspartic Acid Endopeptidases; C509284:BACE2 protein, human; C509280:BACE1 protein, human; D000581:Amidohydrolases; D043524:Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase