Abstract:
Histone writers and erasures – the proteins that
add or remove histone post translational modifications
– are key drivers of epigenetic transcriptional events
inside the cell. Many enzymes that control epigenetic
modifications are dysregulated in human diseases.
For example, overexpression of the erasure histone
deacetylase (HDAC) enzymes can lead to epigenetic
changes in transcription and ultimately disease, such as
cancer. We recently pioneered a simple method called
substrate trapping to isolate HDAC1 substrates using
an inactive HDAC1 mutant. Our recent publication
documented that different HDAC1 mutants preferentially
bound different substrates, suggesting that three mutants
(H141A, F150A, C151A) should be used for efficient
trapping. Based on this observation, we performed a
proteomics-based trapping study of HDAC1 using all
three optimal mutants simultaneously. In this study,
using trapping with three mutants, 12 potential HDAC1
substrates were identified that were not observed when
only a single mutant was used. Although trapping with
three mutants identified novel substrates of HDAC1,
the throughput of the experiment was low compared
to trapping with a single mutant. Therefore, this study
confirms that trapping with a single mutant is simple
and effective, although three mutants may be desirable
when high efficiency or a large number of substrates is
necessar
