HSP70 binds to specific non-coding RNA and regulates human RNA polymerase III.

Molecular chaperones are critical for protein homeostasis and are implicated in several human pathologies such as neurodegeneration and cancer. While the binding of chaperones to nascent and misfolded proteins has been studied in great detail, the direct interaction between chaperones and RNA has not been systematically investigated. Here, we provide the evidence for widespread interaction between chaperones and RNA in human cells.

Operation of a TCA cycle subnetwork in the mammalian nucleus.

Nucleic acid and histone modifications critically depend on the tricarboxylic acid (TCA) cycle for substrates and cofactors. Although a few TCA cycle enzymes have been reported in the nucleus, the corresponding pathways are considered to operate in mitochondria. Here, we show that a part of the TCA cycle is operational also in the nucleus.

The RNA helicase DHX9 establishes nucleolar heterochromatin, and this activity is required for embryonic stem cell differentiation.

Long non-coding RNAs (lncRNAs) have been implicated in the regulation of chromatin conformation and epigenetic patterns. lncRNA expression levels are widely taken as an indicator for functional properties. However, the role of RNA processing in modulating distinct features of the same lncRNA is less understood.

Challenges in the analysis of long noncoding RNA functionality.

Long noncoding RNA (lncRNA) are emerging as important regulators of diverse biological functions. Although mechanistic models are starting to emerge, it is also clear that the lncRNA field needs appropriate model systems in order to better elucidate the functions of lncRNA and their roles in both physiological and pathological conditions. The field of lncRNA is new, and the biochemical and genetic methods used to address function and mechanisms of lncRNA have only recently been developed or adapted from techniques used to investigate protein-coding genes.

lncRNA maturation to initiate heterochromatin formation in the nucleolus is required for exit from pluripotency in ESCs.

The open chromatin of embryonic stem cells (ESCs) condenses into repressive heterochromatin as cells exit the pluripotent state. How the 3D genome organization is orchestrated and implicated in pluripotency and lineage specification is not understood. Here, we find that maturation of the long noncoding RNA (lncRNA) pRNA is required for establishment of heterochromatin at ribosomal RNA genes, the genetic component of nucleoli, and this process is inactivated in pluripotent ESCs.