Volume 23 Issue 9, September 2021

Tissue-resident stem cells are capable of remarkable plasticity in areas of tissue damage, where inflammatory cells accumulate as part of the reparative response. A study in the lung now provides critical insight on how inflammatory signals alter cell-to-cell Notch signalling within the airway niche to drive stem cell plasticity.

With advanced high-throughput technologies, scientists can now use transcriptional signatures to study melanocytes as they become cancer. A new study identifies transcriptional programs at single-cell resolution across platforms and species, which enables prediction of melanoma prognosis and response to immune-checkpoint inhibitor therapy.

Stem cells are the functional units of tissue repair but do not act alone. Studies on flatworms now reveal specialized populations of differentiated cells that transiently emerge to coordinate whole-body regeneration. The stem-cell-centric view of repair processes must be revised to account for the importance of cell fate dynamics beyond the niche.

Enhancer of zeste homolog 2 (EZH2) has been shown to promote development of castration-resistant prostate cancer (CRPC) through various mechanisms. A new study now shows that a phosphorylated EZH2 interacts with the androgen receptor (AR) and reprograms AR transcriptional activity to facilitate transition of CRPC into a lineage infidelity state.

Mice deficient in the piRNA pathway display sterility only in males. Taking advantage of a more representative piRNA pathway in golden hamsters, three studies now demonstrate that the piRNA pathway is essential for fertility in hamsters of both sexes and thus strongly link this small RNA pathway to fertility regulation in both men and women.

Benham-Pyle et al. present a single-cell analysis of planarian regeneration and identify rare amputation-specific cell states in the muscle, epidermis and intestine that are required for patterning and stem cell proliferation.

Using human airway organoids and mouse models, Choi et al. show that an IL-1β–Notch–Fosl2 signalling axis regulates the conversion of secretory cells into alveolar type 2 cells after injury.

Lu, Wang et al. show in mice that the pre-existing embryonic coronary plexus at the inner myocardium undergoes angiogenic expansion through DLL4–NOTCH1 signalling to vascularize the expanding myocardium.

Zhu et al. report that, in response to growth signals, ERK undergoes TRIM15-mediated lysine-63-linked ubiquitination, which facilitates ERK interaction with MEK and therefore enhances ERK activity.

A set of three papers reports that the piRNA pathway is essential for mammalian female fertility based on genetic perturbation experiments performed in golden hamsters.

A set of three papers reports that the piRNA pathway is essential for mammalian female fertility based on genetic perturbation experiments performed in golden hamsters.

A set of three papers reports that the piRNA pathway is essential for mammalian female fertility based on genetic perturbation experiments performed in golden hamsters.

Davies et al. demonstrate that androgen receptor–targeted therapy induces lineage-plastic transcriptional reprogramming, which is mediated by EZH2 and favours stem cell and neuronal gene networks in treatment-resistant prostate cancer.

Constructing a single-cell transcriptional map of primary human epidermal melanocytes, Belote et al. uncover distinct subpopulations of melanocytes, characterize dedifferentiation patterns associated with melanoma prognosis and uncover the unique cellular origins of acral melanoma.