Conserved Structure and Evolution of DPF Domain of PHF10-The Specific Subunit of PBAF Chromatin Remodeling Complex

PHD finger protein 10 promotes cell proliferation by regulating CD44 transcription in gastric cancer

PHD finger protein 10 (PHF10) plays an important role in the tumorigenesis of gastric cancer (GC). However, clinical significance and underlying molecular mechanisms about PHF10 is unclear. In the article, it suggested that PHF10 involved in tumor progression and metastasis based on the analysis of datasets and 190 cases of tumor tissues in GC. And PHF10 provided the diagnostic value with areas under the receiver operating characteristics curve of 0.71 ± 0.069. Then we established GC cell lines MKN28 with PHF10 overexpression and SGC7901 with PHF10 knockdown. CCK8 assay and tumor xenograft experiment showed that upregulation of PHF10 could promote MKN28 cell proliferation, while PHF10 knockdown would inhibit the proliferation of SGC7901 in vitro and vivo. Nevertheless, PHF10 could upregulate CD44 mRNA expression by acting on its promoter at the level of transcription. This effect could be associated with BRG, BAF155 and SNF5, which were conserved subunits of switch/sucrose non-fermentable (SWI/SNF) complex. In conclusion, PHF10 targeting CD44 plays an essential part during the modulation of proliferation of GC cell and may offer a new therapeutic direction for GC.

Contact Inhibition of Proliferation Is Accompanied by Expression of the PHF10D Subunit of the Chromatin Remodeling Complex PBAF in Mouse and Human Cell Lines

PHF10 is a subunit of the PBAF complex, which regulates the expression of many genes in developing and maturing organisms. PHF10 has four isoforms that differ in domain structure. The PHF10A isoform, containing a DPF domain at the C-terminus and 46 amino acids at the N-terminus, is necessary for the expression of proliferation genes; the functions of the other isoforms are less studied. In this work, we have established that, upon contact inhibition of mouse and human cell proliferation caused by the establishment of a tight junction and adherence junction between cells, the expression of the PHF10A isoform stops and instead the PHF10D isoform is expressed, which does not contain DPF-domain and N-terminal sequence. The function of the PHF10D isoform may be associated with the establishment of intercellular contacts.

A novel chromatin-remodeling complex variant, dcPBAF, is involved in maintaining transcription in differentiated neurons

The Polybromo-associated BAF (BRG1- or BRM-associated factors) (PBAF) chromatin-remodeling complex is essential for transcription in mammalian cells. In this study, we describe a novel variant of the PBAF complex from differentiated neuronal cells, called dcPBAF, that differs from the canonical PBAF existing in proliferating neuroblasts. We describe that in differentiated adult neurons, a specific subunit of PBAF, PHF10, is replaced by a PHF10 isoform that lacks N- and C-terminal domains (called PHF10D). In addition, dcPBAF does not contain the canonical BRD7 subunit. dcPBAF binds promoters of the actively transcribed neuron-specific and housekeeping genes in terminally differentiated neurons of adult mice. Furthermore, in differentiated human neuronal cells, PHF10D-containing dcPBAF maintains a high transcriptional level at several neuron-specific genes.

Targeting Chromatin-Remodeling Factors in Cancer Cells: Promising Molecules in Cancer Therapy

ATP-dependent chromatin-remodeling complexes can reorganize and remodel chromatin and thereby act as important regulator in various cellular processes. Based on considerable studies over the past two decades, it has been confirmed that the abnormal function of chromatin remodeling plays a pivotal role in genome reprogramming for oncogenesis in cancer development and/or resistance to cancer therapy. Recently, exciting progress has been made in the identification of genetic alteration in the genes encoding the chromatin-remodeling complexes associated with tumorigenesis, as well as in our understanding of chromatin-remodeling mechanisms in cancer biology. Here, we present preclinical evidence explaining the signaling mechanisms involving the chromatin-remodeling misregulation-induced cancer cellular processes, including DNA damage signaling, metastasis, angiogenesis, immune signaling, etc. However, even though the cumulative evidence in this field provides promising emerging molecules for therapeutic explorations in cancer, more research is needed to assess the clinical roles of these genetic cancer targets.

The TRIPLE PHD FINGERS proteins are required for SWI/SNF complex-mediated +1 nucleosome positioning and transcription start site determination in Arabidopsis

Eukaryotes have evolved multiple ATP-dependent chromatin remodelers to shape the nucleosome landscape. We recently uncovered an evolutionarily conserved SWItch/Sucrose Non-Fermentable (SWI/SNF) chromatin remodeler complex in plants reminiscent of the mammalian BAF subclass, which specifically incorporates the MINUSCULE (MINU) catalytic subunits and the TRIPLE PHD FINGERS (TPF) signature subunits. Here we report experimental evidence that establishes the functional relevance of TPF proteins for the complex activity. Our results show that depletion of TPF triggers similar pleiotropic phenotypes and molecular defects to those found in minu mutants. Moreover, we report the genomic location of MINU2 and TPF proteins as representative members of this SWI/SNF complex and their impact on nucleosome positioning and transcription. These analyses unravel the binding of the complex to thousands of genes where it modulates the position of the +1 nucleosome. These targets tend to produce 5′-shifted transcripts in the tpf and minu mutants pointing to the participation of the complex in alternative transcription start site usage. Interestingly, there is a remarkable correlation between +1 nucleosome shift and 5′ transcript length change suggesting their functional connection. In summary, this study unravels the function of a plant SWI/SNF complex involved in +1 nucleosome positioning and transcription start site determination.