BAZ1A

BAZ1A Full Name

bromodomain adjacent to zinc finger domain, 1A

BAZ1A Introduction

Bromodomain adjacent to zinc finger domain protein 1A (BAZ1A), also widely known as ATP-utilizing chromatin assembly and remodeling factor 1 (ACF1), is a critical epigenetic regulator in eukaryotic cells. It serves as the essential accessory and targeting subunit of the ATP-dependent chromatin assembly factor (ACF) complex, a prominent member of the ISWI (imitation switch) family of chromatin remodelers. Structurally, BAZ1A possesses multiple functional domains, including a plant homeodomain (PHD) finger and a bromodomain, which enable it to "read" specific epigenetic marks such as acetylated histones.

Figure 1. Mammalian ISWI family chromatin remodeling complexes. (Source: Aydin ÖZ, et al. 2014)

The primary physiological function of BAZ1A is to orchestrate chromatin architecture by regulating the spacing and positioning of nucleosomes. By harnessing the energy derived from ATP hydrolysis via its partner ATPase, the BAZ1A-containing ACF complex slides nucleosomes along the DNA strand to create evenly spaced chromatin arrays. This dynamic remodeling is fundamental for regulating cellular access to the underlying DNA sequence. Consequently, BAZ1A is deeply involved in critical nuclear processes, including transcriptional regulation, DNA replication, and the maintenance of genomic stability. Notably, BAZ1A plays a vital role in the cellular DNA damage response (DDR). Upon genomic injury, it rapidly accumulates at DNA double-strand break (DSB) sites to facilitate localized chromatin relaxation, thereby allowing critical downstream DNA repair machinery to access the lesions.

Clinically, the dysregulation of BAZ1A is increasingly implicated in various pathologies, spanning from human malignancies to vascular diseases. In oncology, abnormal BAZ1A expression is closely associated with tumorigenesis and altered chemoresistance. For instance, recent studies in colorectal cancer have revealed that alternative splicing of BAZ1A disrupts the DNA damage response, promoting tumor progression while concurrently altering tumor sensitization to specific chemotherapies. Furthermore, BAZ1A acts as an oncogenic driver in hepatocellular carcinoma and ovarian carcinosarcoma. Beyond cancer, emerging evidence highlights its novel role in cardiovascular pathology; the interaction between BAZ1A and its regulatory long non-coding RNA (BAZ1A-AS1) has been shown to drive vascular smooth muscle cell proliferation and neointima formation. Additionally, de novo genetic mutations in BAZ1A have been linked to syndromic forms of intellectual disability due to impaired transcriptional regulation during neurodevelopment. As research rapidly expands, BAZ1A is recognized not only as a master regulator of the epigenome but also as a promising therapeutic target.

Alternate Names for BAZ1A

BAZ1A; bromodomain adjacent to zinc finger domain, 1A; bromodomain adjacent to zinc finger domain protein 1A; ACF1; hACF1; WALp1; WCRF180; Acf1; ACF1, drosophila, homolog of; ATP dependent chromatin remodelling protein; ATP utilizing chromatin assembly an

• 1. Aydin ÖZ, et al. ISWI chromatin remodeling complexes in the DNA damage response. Cell Cycle. 2014;13(19):3016-25.
  2. Mohan N, et al. Alternative splicing of BAZ1A in colorectal cancer disrupts the DNA damage response and increases chemosensitization. Cell Death Dis. 2024 Aug 7;15(8):570.