USP4 is regulated by Akt phosphorylation and deubiquitylates TGF-beta type I receptor

Stability and membrane localization of Transforming growth factor-β (TGF-β) type I receptor (TβRI) is essential for controlling TGF-β signaling. TβRI is targeted for ubiquitination-mediated degradation by Smad7/Smurf2 complex. However, it is unclear whether polyubiquitin modified TβRI can be reversed. Here we performed a genome-wide gain of function screen and identified ubiquitin-specific protease (USP) 4 as a strong inducer of TGF-β signaling. Putative oncogenic USP4 was found to interact with TβRI as deubiquitinating enzyme thus maintains TβR1 levels at the plasma membrane. Depletion of USP4 mitigates TGF-β-induced breast cancer cell migration, epithelial to mesenchymal transition and metastasis. Importantly, Akt/Protein kinase B (PKB), which has been associated with poor prognosis in breast cancer, associates with and phosphorylates USP4. Akt mediated phosphorylation relocates USP4 to cytoplasm and membrane and is required for maintaining its protein stability. Moreover, Akt-induced breast cancer cell migration was inhibited by USP4 depletion and TβRI kinase inhibition. Our results identified USP4 as an important determinant for crosstalk between TGF-β and Akt, which provides new opportunities for cancer treatment

Whole genome functional analysis identifies novel components required for mitotic spindle integrity in human cells

A loss-of-function screen for siRNAs that arrest human cells in metaphase reveals genes involved in mitotic spindle integrity

The transcription factor ZNF469 regulates collagen production in liver fibrosis.

Non-alcoholic fatty liver disease (NAFLD) - characterized by excess accumulation of fat in the liver - now affects one third of the world's population. As NAFLD progresses, extracellular matrix components including collagen accumulate in the liver causing tissue fibrosis, a major determinant of disease severity and mortality. To identify transcriptional regulators of fibrosis, we computationally inferred the activity of transcription factors (TFs) relevant to fibrosis by profiling the matched transcriptomes and epigenomes of 108 human liver biopsies from a deeply-characterized cohort of patients spanning the full histopathologic spectrum of NAFLD. CRISPR-based genetic knockout of the top 100 TFs identified ZNF469 as a regulator of collagen expression in primary human hepatic stellate cells (HSCs). Gain- and loss-of-function studies established that ZNF469 regulates collagen genes and genes involved in matrix homeostasis through direct binding to gene bodies and regulatory elements. By integrating multiomic large-scale profiling of human biopsies with extensive experimental validation we demonstrate that ZNF469 is a transcriptional regulator of collagen in HSCs. Overall, these data nominate ZNF469 as a previously unrecognized determinant of NAFLD-associated liver fibrosis

The transcription factor ZNF469 regulates collagen production in liver fibrosis.

Metabolic dysfunction-associated steatotic liver disease (MASLD) - characterized by excess accumulation of fat in the liver - now affects one-third of the world's population. As MASLD progresses, extracellular matrix components including collagen accumulate in the liver, causing tissue fibrosis, a major determinant of disease severity and mortality. To identify transcriptional regulators of fibrosis, we computationally inferred the activity of transcription factors (TFs) relevant to fibrosis by profiling the matched transcriptomes and epigenomes of 108 human liver biopsies from a deeply characterized cohort of patients spanning the full histopathologic spectrum of MASLD. CRISPR-based genetic KO of the top 100 TFs identified ZNF469 as a regulator of collagen expression in primary human hepatic stellate cells (HSCs). Gain- and loss-of-function studies established that ZNF469 regulates collagen genes and genes involved in matrix homeostasis through direct binding to gene bodies and regulatory elements. By integrating multiomic large-scale profiling of human biopsies with extensive experimental validation, we demonstrate that ZNF469 is a transcriptional regulator of collagen in HSCs. Overall, these data nominate ZNF469 as a previously unrecognized determinant of MASLD-associated liver fibrosis

Impaired Design Fluency Is a Marker of Pathological Cognitive Aging; Results from the Korean Longitudinal Study on Health and Aging

ObjectiveaaWe investigated neuropsychological markers that can be used to discriminate pathological cognitive aging from normal cognitive aging. MethodsaaWe administered frontal lobe function tests including the Wisconsin Card Sorting Test (WCST), digit span test, lexical fluency test, fixed condition design fluency test, and Trail Making Test B (TMT-B) to 92 individuals with pathological cognitive aging (PCA) and 222 individuals with normal cognitive aging (NCA). We examined the main effects of participants ’ diagnoses (PCA, NCA) and age (65-69 years old, 70-74 years old and 75 years old or over) on their test performance using multivariate analysis of variance. ResultsaaThe main effects of both the diagnosis (F=2.860, p=0.002) and the age group (F=2.484, p<0.001) were significant. The PCA group showed lower performance on the backward digit span test (F=14.306, p<0.001), fixed condition design fluency test (F=8.347, p=0.004) and also exhibited perseverative errors in the WCST (F=4.19, p=0.042) compared with the NCA group. The main effect of the diagnosis on the backward digit span test and the fixed condition design fluency test remained significant after Bonferroni correction

Identification of Novel Genes and Pathways Regulating SREBP Transcriptional Activity

BACKGROUND: Lipid metabolism in mammals is orchestrated by a family of transcription factors called sterol regulatory element-binding proteins (SREBPs) that control the expression of genes required for the uptake and synthesis of cholesterol, fatty acids, and triglycerides. SREBPs are thus essential for insulin-induced lipogenesis and for cellular membrane homeostasis and biogenesis. Although multiple players have been identified that control the expression and activation of SREBPs, gaps remain in our understanding of how SREBPs are coordinated with other physiological pathways. METHODOLOGY: To identify novel regulators of SREBPs, we performed a genome-wide cDNA over-expression screen to identify proteins that might modulate the transcription of a luciferase gene driven from an SREBP-specific promoter. The results were verified through secondary biological assays and expression data were analyzed by a novel application of the Gene Set Enrichment Analysis (GSEA) method. CONCLUSIONS/SIGNIFICANCE: We screened 10,000 different cDNAs and identified a number of genes and pathways that have previously not been implicated in SREBP control and cellular cholesterol homeostasis. These findings further our understanding of lipid biology and should lead to new insights into lipid associated disorders