Microglia: Immune and non-immune functions.

As resident macrophages of the central nervous system (CNS), microglia are associated with diverse functions essential to the developing and adult brain during homeostasis and disease. They are aided in their tasks by intricate bidirectional communication with other brain cells under steady-state conditions as well as with infiltrating peripheral immune cells during perturbations. Harmonious cell-cell communication involving microglia are considered crucial to maintain the healthy state of the tissue environment and to overcome pathology such as neuroinflammation.

Current tools to interrogate microglial biology.

Microglial cells perform a plethora of functions in the central nervous system (CNS), involving them in brain development, maintenance of homeostasis in adulthood, and CNS diseases. Significant technical advancements have prompted the development of novel systems adapted to analyze microglia with increasing specificity and intricacy. The advent of single-cell technologies combined with targeted mouse models has been decisive in deciphering microglia heterogeneity and dissecting microglial functions.

Correction to 'Elucidation of the BMI1 interactome identifies novel regulatory roles in glioblastoma'.

[This corrects the article DOI: 10.1093/narcan/zcab009.].

Elucidation of the BMI1 interactome identifies novel regulatory roles in glioblastoma.

Glioblastoma (GBM) is the most common and aggressive intrinsic brain tumour in adults. Epigenetic mechanisms controlling normal brain development are often dysregulated in GBM. Among these, BMI1, a structural component of the Polycomb Repressive Complex 1 (PRC1), which promotes the H2AK119ub catalytic activity of Ring1B, is upregulated in GBM and its tumorigenic role has been shown and .

Selective modification of a native protein in a patient tissue homogenate using palladium nanoparticles.

We have developed new benign palladium nanoparticles able to catalyze the Suzuki-Miyaura cross-coupling reaction on human thyroglobulin (Tg), a naturally iodinated protein produced by the thyroid gland, in homogenates from patients' tissues. This represents the first example of a chemoselective native protein modification using transition metal nanoobjects in near-organ medium.

Correction to: c-MYC overexpression induces choroid plexus papillomas through a T-cell mediated inflammatory mechanism.

In the original version of this article [1], there was 1 error in the affiliation of the European Institute of Oncology (affiliation 3). In this correction article the updated affiliation is shown for clarification.

c-MYC overexpression induces choroid plexus papillomas through a T-cell mediated inflammatory mechanism.

Choroid plexus tumours (CPTs) account for 2-5% of brain tumours in children. They can spread along the neuraxis and can recur after treatment. Little is known about the molecular mechanisms underlying their formation and only few high fidelity mouse models of p53-deficient malignant CPTs are available.

Regulatory mechanisms of incomplete huntingtin mRNA splicing.

Huntington's disease is caused by a CAG repeat expansion in exon 1 of the HTT gene. We have previously shown that exon 1 HTT does not always splice to exon 2 producing a small transcript (HTTexon1) that encodes the highly pathogenic exon 1 HTT protein. The mechanisms by which this incomplete splicing occurs are unknown.

PLGA-PEG-supported Pd Nanoparticles as Efficient Catalysts for Suzuki-Miyaura Coupling Reactions in Water.

Chemical transformations that can be performed selectively under physiological conditions are highly desirable tools to track biomolecules and manipulate complex biological processes. Here, we report a new nanocatalyst consisting of small palladium nanoparticles stabilized on the surface of PLGA-PEG nanoparticles that show excellent catalytic activity for the modification of biological building blocks through Suzuki-Miyaura cross-coupling reactions in water. Brominated or iodinated amino acids were coupled with aryl boronic acids in phosphate buffer in good yields.

Palladium: a future key player in the nanomedical field?

Metal nanostructures offer invaluable possibilities for targeted drug delivery, detection/diagnosis and imaging. Whereas iron, gold, silver and platinum nanoarchitectures have largely dominated this field to date, several hurdles impede the widespread application of those nanopharmaceuticals in a clinical context. Therefore, technologies based on alternative metals are now being evaluated for their potential in medical applications.

Designing logical codon reassignment - Expanding the chemistry in biology.

Over the last decade, the ability to genetically encode unnatural amino acids (UAAs) has evolved rapidly. The programmed incorporation of UAAs into recombinant proteins relies on the reassignment or suppression of canonical codons with an amino-acyl tRNA synthetase/tRNA (aaRS/tRNA) pair, selective for the UAA of choice. In order to achieve selective incorporation, the aaRS should be selective for the designed tRNA and UAA over the endogenous amino acids and tRNAs.

Site-specific control of N7-metal coordination in DNA by a fluorescent purine derivative.

A synthetic strategy that utilizes O6-protected 8-bromoguanosine gives broad access to C8-guanine derivatives with phenyl, pyridine, thiophene, and furan substituents. The resulting 8-substituted 2'-deoxyguanosines are push-pull fluorophores that can exhibit environmentally sensitive quantum yields (Φ=0.001-0.

Fluorescence properties of 8-(2-pyridyl)guanine "2PyG" as compared to 2-aminopurine in DNA.

Because of their environment-sensitive fluorescence quantum yields, base analogues such as 2-aminopurine (2AP), 6-methylisoxanthopterin (6-MI), and 3-methylisoxanthopterin (3-MI) are widely used in nucleic-acid folding and catalysis assays. Emissions from these guanine mimics are quenched by base-stacking interactions and collisions with purine residues. Fluorescent base analogues that remain highly emissive in folded nucleic acids can provide sensitive means to differentiate DNA/RNA structures by participating in energy transfer from proximal ensembles of unmodified nucleobases.

Highly fluorescent guanosine mimics for folding and energy transfer studies.

Guanosines with substituents at the 8-position can provide useful fluorescent probes that effectively mimic guanine residues even in highly demanding model systems such as polymorphic G-quadruplexes and duplex DNA. Here, we report the synthesis and photophysical properties of a small family of 8-substituted-2'-deoxyguanosines that have been incorporated into the human telomeric repeat sequence using phosphoramidite chemistry. These include 8-(2-pyridyl)-2'-deoxyguanosine (2PyG), 8-(2-phenylethenyl)-2'-deoxyguanosine (StG) and 8-[2-(pyrid-4-yl)-ethenyl]-2'-deoxyguanosine (4PVG).

Cation-mediated energy transfer in G-quadruplexes revealed by an internal fluorescent probe.

A single pyridine unit incorporated into G-quadruplex DNA has revealed efficient energy transfer reactions in cation-containing G-quadruplexes. 8-(2-Pyridyl)-2'-deoxyguanosine, "2PyG", is a highly sensitive internal fluorescent probe of G-quadruplex folding and energy transfer. 2PyG was minimally disruptive to G-quadruplex folding and exhibited intense fluorescence, even when it was base-stacked with other guanine residues.