Pim oncogenes are overexpressed in a wide range of tumours from a haematological and epithelial origin. Pim genes encode serine/threonine kinases that have been shown to counteract the increased sensitivity to apoptosis induction that is associated with MYC-driven tumorigenesis. Recently, considerable progress has been made in characterizing the pathways of PIM-mediated survival signalling. Given the unique structure of their active site and the minimal phenotype of mice mutant for all Pim family members, these oncogenes might be promising targets for highly specific and selective drugs with favourable toxicity profiles. In this Review, we discuss the physiological functions and oncogenic activities of Pim kinases.

Summary 7-methylguanosine (m7G) is present at mRNA caps and at defined internal positions within tRNAs and rRNAs. However, its detection within low-abundance mRNAs and microRNAs (miRNAs) has been hampered by a lack of sensitive detection strategies. Here, we adapt a chemical reactivity assay to detect internal m7G in miRNAs. Using this technique (Borohydride Reduction sequencing [BoRed-seq]) alongside RNA immunoprecipitation, we identify m7G within a subset of miRNAs that inhibit cell migration. We show that the METTL1 methyltransferase mediates m7G methylation within miRNAs and that this enzyme regulates cell migration via its catalytic activity. Using refined mass spectrometry methods, we map m7G to a single guanosine within the let-7e-5p miRNA. We show that METTL1-mediated methylation augments let-7 miRNA processing by disrupting an inhibitory secondary structure within the primary miRNA transcript (pri-miRNA). These results identify METTL1-dependent N7-methylation of guanosine as a new RNA modification pathway that regulates miRNA structure, biogenesis, and cell migration.

DDX3X is a multifunctional RNA helicase with documented roles in different cancer types. Here, we demonstrate that DDX3X plays an oncogenic role in breast cancer cells by modulating the cell cycle. Depletion of DDX3X in MCF7 cells slows cell proliferation by inducing a G1 phase arrest. Notably, DDX3X inhibits expression of Kruppel‐like factor 4 (KLF4), a transcription factor and cell cycle repressor. Moreover, DDX3X directly interacts with KLF4 mRNA and regulates its splicing. We show that DDX3X‐mediated repression of KLF4 promotes expression of S‐phase inducing genes in MCF7 breast cancer cells. These findings provide evidence for a novel function of DDX3X in regulating expression and downstream functions of KLF4, a master negative regulator of the cell cycle.

Cytokines are critical checkpoints of inflammation. The treatment of human autoimmune disease has been revolutionized by targeting inflammatory cytokines as key drivers of disease pathogenesis. Despite this, there exist numerous pitfalls when translating preclinical data into the clinic. We developed an integrative biology approach combining human disease transcriptome data sets with clinically relevant in vivo models in an attempt to bridge this translational gap. We chose interleukin-22 (IL-22) as a model cytokine because of its potentially important proinflammatory role in epithelial tissues. Injection of IL-22 into normal human skin grafts produced marked inflammatory skin changes resembling human psoriasis. Injection of anti-IL-22 monoclonal antibody in a human xenotransplant model of psoriasis, developed specifically to test potential therapeutic candidates, efficiently blocked skin inflammation. Bioinformatic analysis integrating both the IL-22 and anti-IL-22 cytokine transcriptomes and mapping them onto a psoriasis disease gene coexpression network identified key cytokine-dependent hub genes. Using knockout mice and small-molecule blockade, we show that one of these hub genes, the so far unexplored serine/threonine kinase PIM1, is a critical checkpoint for human skin inflammation and potential future therapeutic target in psoriasis. Using in silico integration of human data sets and biological models, we were able to identify a new target in the treatment of psoriasis.

Chromatin is highly dynamic, undergoing continuous global changes in its structure and type of histone and DNA modifications governed by processes such as transcription, repair, replication, and recombination. Members of the chromodomain helicase DNA-binding (CHD) family of enzymes are ATP-dependent chromatin remodelers that are intimately involved in the regulation of chromatin dynamics, altering nucleosomal structure and DNA accessibility. Genetic studies in yeast, fruit flies, zebrafish, and mice underscore essential roles of CHD enzymes in regulating cellular fate and identity, as well as proper embryonic development. With the advent of next-generation sequencing, evidence is emerging that these enzymes are subjected to frequent DNA copy number alterations or mutations and show aberrant expression in malignancies and other human diseases. As such, they might prove to be valuable biomarkers or targets for therapeutic intervention.

Chromodomain helicase DNA-binding (CHD) chromatin remodelers regulate transcription and DNA repair. They govern cell-fate decisions during embryonic development and are often deregulated in human pathologies. Chd1-8 show upon germline disruption pronounced, often developmental lethal phenotypes. Here we show that contrary to Chd1-8 disruption, Chd9 -/animals are viable, fertile and display no developmental defects or disease predisposition. Germline deletion of Chd9 only moderately affects gene expression in tissues and derived cells, whereas acute depletion in human cancer cells elicits more robust changes suggesting that CHD9 is a highly context-dependent chromatin regulator that, surprisingly, is dispensable for mouse development.

(1) None of 115 non-related Yugoslav ataxic patients belong to any known SCAs nor to DRPLA gene; (2) the distribution of SCA17 alleles in the Yugoslav population is consistent with the distribution in other populations and (3) the paucity of alleles with more than 39 repeats could suggest that SCA17 is very rare in the Yugoslav population.

Vital processes such as transcription, repair, replication and recombination continuously shape cellular chromatin landscape. The chromodomain helicase DNA‐binding (CHD) family of enzymes regulate chromatin dynamics by utilising energy from ATP hydrolysis to alter nucleosomal position, structure and composition, thereby modulating accessibility of the underlying DNA sequence. The CHD enzymes are highly conserved in evolution, and genetic studies in fungi, plants and animals demonstrate their critical roles in regulation of cellular identity and fate and organismal development. Advances in genomic studies over the past two decades led to the identification of frequent DNA copy‐number alterations, mutations and aberrant expression of CHDs in human malignancies and various disorders, highlighting their importance as relevant biomarkers or targets for therapeutic intervention. Key Concepts CHD family of enzymes (CHD1‐9) are evolutionary conserved ATP‐dependent chromatin remodelers that mobilise nucleosomes to regulate DNA‐templated processes, such as transcription, replication and repair. They are critical for normal organismal development and are frequently mutated in human disorders and cancers. Chromodomain helicase DNA‐binding proteins (CHD1‐9) are evolutionary conserved family of ATP‐dependent chromatin remodelers that mobilise nucleosomes to regulate DNA‐templated processes such as transcription, replication and DNA repair. CHD enzymes share a common domain structure: two N‐terminal chromodomains, a central ATPase/helicase domain, and a C‐terminal DNA‐binding domain. CHD proteins play crucial roles in diverse cellular processes, including embryonic development, stem cell maintenance and differentiation, and tissue‐specific gene expression. Dysregulation of CHD proteins has been associated with various human diseases, including cancer and neurodevelopmental disorders. CHD proteins are attractive targets for the development of new therapies for diseases associated with chromatin dysfunction. Understanding the molecular mechanisms underlying the function of CHD proteins may pave the way for the development of new drugs that target these proteins and improve the treatment of a variety of human diseases.