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Updated: May 16, 2026

Method for Measuring the Activity of Deubiquitinating Enzymes in Cell Lines and Tissue Samples
Published on: May 10, 2015
The deubiquitinase USP44 is a tumor suppressor that protects against chromosome missegregation
Andrew J Holland1, Don W Cleveland
1Ludwig Institute for Cancer Research and Department of Cellular and Molecular Medicine, UCSD, La Jolla, California 92093-0670, USA. a1holland@ucsd.edu
Abstract:
The mitotic checkpoint plays an important role in preventing chromosome segregation errors and the production of aneuploid progeny. In this issue, Zhang et al. examine mice and cells lacking the deubiquitinating enzyme USP44. Surprisingly, they find that USP44 prevents chromosome segregation errors through a function independent of its previously identified role in the mitotic checkpoint. Usp44-null animals develop aneuploidy and experience increased rates of tumorigenesis, implicating USP44 as novel tumor suppressor.
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