Related Experiment Video
Updated: Oct 20, 2026

X-Ray Crystallography to Study the Oligomeric State Transition of the Thermotoga maritima M42 Aminopeptidase TmPep1050
Published on: May 13, 2020
A 45 amino acid residue domain necessary and sufficient for proteolytic cleavage of the MAP1B polyprotein precursor
M Tögel1, R Eichinger, G Wiche
1Institute of Biochemistry and Molecular Cell Biology, Vienna Biocenter, University of Vienna, Austria.
Abstract:
The microtubule-associated proteins 1B and 1A are synthesized as polyprotein precursors which are rapidly cleaved to give rise to heavy and light chains constituting the respective microtubule-associated protein 1B or microtubule-associated protein 1A complex. To identify domains necessary for precursor processing, we expressed microtubule-associated protein 1B deletion mutants in fibroblasts and monitored proteolytic cleavage of the precursor proteins by immunoblot analysis. We found that a novel hydrophilic, proline-rich 45 amino acid domain containing the cleavage site is necessary and sufficient for processing. This domain is conserved in microtubule-associated protein 1A. Additional sequences in the N-terminal half of the heavy chain contribute to the efficiency of cleavage.
Related Concept Videos
Mitochondrial Precursor Proteins
Most of the mitochondrial precursors...
Translocation of Proteins into the Mitochondria
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
Conservation of Protein Domains Over Different Proteins
A limited set of protein domains often duplicate and recombine during evolution. These domains can be organized in different combinations to form...
Microtubule Associated Proteins (MAPs)
Insertion of Single-pass Transmembrane Proteins in the RER
Integral transmembrane proteins possess transmembrane and extra membrane domains. The transmembrane domains are primarily made of 20-25 hydrophobic amino acids arranged in a helical secondary confirmation. These...
Insertion of Multi-pass Transmembrane Proteins in the RER
The multipass transmembrane proteins are the type IV integral membrane proteins with multiple topogenic sequences determining their spatial arrangement in the ER membrane. Nearly all multipass proteins lack a cleavable signal sequence and use...

