The monocytic leukemia zinc finger protein MOZ is a histone acetyltransferase

Area of Science:

• Molecular Biology
• Cancer Genetics

Background:

• The monocytic leukemia zinc finger protein (MOZ) gene is frequently rearranged in acute myeloid leukemia (AML).
• Fusion partners of MOZ, such as CBP, p300, and TIF2, are known transcriptional coactivators with histone acetyltransferase (HAT) activity.
• MOZ protein contains a putative acetyl CoA-binding motif, suggesting it may possess HAT activity.

Purpose of the Study:

• To investigate whether MOZ possesses intrinsic histone acetyltransferase (HAT) activity.
• To characterize the functional domains of the MOZ protein, including its transcriptional regulatory capabilities.

Main Methods:

• Biochemical assays were employed to directly assess the HAT activity of MOZ.
• Functional domain analysis was performed to identify transcriptional repression and activation domains within MOZ.
• Yeast-based transcription activation assays were utilized to evaluate the function of the MOZ activation domain.

Main Results:

• Direct evidence was presented demonstrating that MOZ possesses intrinsic HAT activity.
• MOZ was found to have a transcriptional repression domain at its N-terminus and a transcriptional activation domain at its C-terminus.
• The MOZ C-terminal activation domain, although lacking sequence similarity to yeast proteins, could activate transcription in yeast when tethered.

Conclusions:

• MOZ functions as a histone acetyltransferase (HAT).
• MOZ exhibits characteristics of a transcriptional coregulator, possessing both repression and activation domains.
• These findings support the hypothesis that aberrant acetylation mediated by abnormal MOZ proteins plays a role in leukemogenesis.