Luca Ducoli
Postdoctoral Scholar, Dermatology
Stanford Advisors
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Paul Khavari, Postdoctoral Faculty Sponsor
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Paul Khavari, Postdoctoral Research Mentor
All Publications
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Glucose binds and activates NSUN2 to promote translation and epidermal differentiation.
Nucleic acids research
2024
Abstract
Elevations in intracellular glucose concentrations are essential for epithelial cell differentiation by mechanisms that are not fully understood. Glucose has recently been found to directly bind several proteins to alter their functions to enhance differentiation. Among the newly identified glucose-binding proteins is NSUN2, an RNA-binding protein that we identified as indispensable for epidermal differentiation. Glucose was found to bind conserved sequences within NSUN2, enhancing its binding to S-adenosyl-L-methionine and boosting its enzymatic activity. Additionally, glucose enhanced NSUN2's proximity to proteins involved in mRNA translation, with NSUN2 modulating global messenger RNA (mRNA) translation, particularly that of key pro-differentiation mRNAs containing m5C modifications, such as GRHL3. Glucose thus engages diverse molecular mechanisms beyond its energetic roles to facilitate cellular differentiation processes.
View details for DOI 10.1093/nar/gkae1097
View details for PubMedID 39565212
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Mitochondrial Raf1 Regulates Glutamine Catabolism.
bioRxiv : the preprint server for biology
2024
Abstract
Raf kinases play vital roles in normal mitogenic signaling and cancer, however, the identities of functionally important Raf-proximal proteins throughout the cell are not fully known. Raf1 proximity proteomics/BioID in Raf1-dependent cancer cells unexpectedly identified Raf1-adjacent proteins known to reside in the mitochondrial matrix. Inner-mitochondrial localization of Raf1 was confirmed by mitochondrial purification and super-resolution microscopy. Inside mitochondria, Raf1 associated with glutaminase (GLS) in diverse human cancers and enabled glutaminolysis, an important source of biosynthetic precursors in cancer. These impacts required Raf1 kinase activity and were independent of canonical MAP kinase pathway signaling. Kinase-dead mitochondrial matrix-localized Raf1 impaired glutaminolysis and tumorigenesis in vivo. These data indicate that Raf1 localizes inside mitochondria where it interacts with GLS to engage glutamine catabolism and support tumorigenesis.
View details for DOI 10.1101/2024.03.08.581297
View details for PubMedID 38496616
View details for PubMedCentralID PMC10942467
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Analyzing RNA-Protein Interactions by Cross-Link Rates and CLIP-seq Libraries.
Current protocols
2023; 3 (1): e659
Abstract
UV cross-linking-based methods are the most common tool to explore in vivo RNA-protein interactions. UV cross-linking enables the freezing of direct interactions in the cell, which can then be mapped by high-throughput sequencing through a family of methods termed CLIP-seq. CLIP-seq measures the distribution of cross-link events by purifying a protein of interest and sequencing the covalently bound RNA fragments. However, there are disagreements and ambiguities as to which proteins are RNA-binding proteins and what interactions are significant as all proteins contact all RNAs at some frequency. Here we describe a protocol for both determining RNA-protein interactions through a combination of RNA library preparation and the measurement of absolute cross-link rates, which helps determine what proteins are RNA-binding proteins and what interactions are significant. This protocol, comprising an updated form of the easyCLIP protocol, describes guidelines for RNA library preparation, oligo and protein standard construction, and the measurement of cross-link rates. These methods are easily visualizable through their fluorescent labels and can be adapted to study RNA-binding properties of both functional, high affinity RNA-binding proteins, and the accidental RNA interactions of non-RNA-binding proteins. © 2023 Wiley Periodicals LLC. Basic Protocol 1: RNA library construction Basic Protocol 2: Determining UV cross-link rates Support Protocol 1: Cross-linking and lysing cells Support Protocol 2: Adapter preparation Support Protocol 3: Preparation of cross-linked RBP standard.
View details for DOI 10.1002/cpz1.659
View details for PubMedID 36705610
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The p300/CBP Inhibitor A485 Normalizes Psoriatic Fibroblast Gene Expression In Vitro and Reduces Psoriasis-Like Skin Inflammation In Vivo.
The Journal of investigative dermatology
2022
Abstract
Psoriasis is a chronic inflammatory skin disease that often recurs at the same locations, indicating potential epigenetic changes in lesional skin cells. In this study, we discovered that fibroblasts isolated from psoriatic skin lesions retain an abnormal phenotype even after several passages in culture. Transcriptomic profiling revealed the upregulation of several genes, including the extra domain A splice variant of fibronectin and ITGA4 in psoriatic fibroblasts. A phenotypic library screening of small-molecule epigenetic modifier drugs revealed that selective CBP/p300 inhibitors were able to rescue the psoriatic fibroblast phenotype, reducing the expression levels of extra domain A splice variant of fibronectin and ITGA4. In the imiquimod-induced mouse model of psoriasis-like skin inflammation, systemic treatment with A485, a potent CBP/p300 blocker, significantly reduced skin inflammation, immune cell recruitment, and inflammatory cytokine production. Our findings indicate that epigenetic reprogramming might represent a new approach for the treatment and/or prevention of relapses of psoriasis.
View details for DOI 10.1016/j.jid.2022.09.004
View details for PubMedID 36174717
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Functional annotation of human long noncoding RNAs via molecular phenotyping
GENOME RESEARCH
2020; 30 (7): 1060–72
View details for DOI 10.1101/gr.254219.119.
View details for Web of Science ID 000554900100011
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Functional annotation of human long noncoding RNAs via molecular phenotyping.
Genome research
2020
Abstract
Long noncoding RNAs (lncRNAs) constitute the majority of transcripts in the mammalian genomes, and yet, their functions remain largely unknown. As part of the FANTOM6 project, we systematically knocked down the expression of 285 lncRNAs in human dermal fibroblasts and quantified cellular growth, morphological changes, and transcriptomic responses using Capped Analysis of Gene Expression (CAGE). Antisense oligonucleotides targeting the same lncRNAs exhibited global concordance, and the molecular phenotype, measured by CAGE, recapitulated the observed cellular phenotypes while providing additional insights on the affected genes and pathways. Here, we disseminate the largest-to-date lncRNA knockdown data set with molecular phenotyping (over 1000 CAGE deep-sequencing libraries) for further exploration and highlight functional roles for ZNF213-AS1 and lnc-KHDC3L-2.
View details for DOI 10.1101/gr.254219.119
View details for PubMedID 32718982