ZIC1 is a context-dependent medulloblastoma driver in the rhombic lip.

Transcription factors are frequent cancer driver genes, exhibiting noted specificity based on the precise cell of origin. We demonstrate that ZIC1 exhibits loss-of-function (LOF) somatic events in group 4 (G4) medulloblastoma through recurrent point mutations, subchromosomal deletions and mono-allelic epigenetic repression (60% of G4 medulloblastoma). In contrast, highly similar SHH medulloblastoma exhibits distinct and diametrically opposed gain-of-function mutations and copy number gains (20% of SHH medulloblastoma).

Early rhombic lip Protogenin stem cells in a human-specific neurovascular niche initiate and maintain group 3 medulloblastoma.

We identify a population of Protogenin-positive (PRTG) MYC NESTIN stem cells in the four-week-old human embryonic hindbrain that subsequently localizes to the ventricular zone of the rhombic lip (RL). Oncogenic transformation of early Prtg rhombic lip stem cells initiates group 3 medulloblastoma (Gr3-MB)-like tumors. PRTG stem cells grow adjacent to a human-specific interposed vascular plexus in the RL, a phenotype that is recapitulated in Gr3-MB but not in other types of medulloblastoma.

Stem chewing lice on Cretaceous feathers preserved in amber.

Phthirapteran lice (true lice or parasitic lice) are a major group of ectoparasitic insects living on their bird or mammal hosts during their entire life cycle. Due to their highly specialized lifestyles, they are extremely poorly represented in fossil records. Molecular clock estimations have speculated extensively about the origin time of parasitic lice, yet none have been confirmed unequivocally.

Cimbicidae (Hymenoptera, 'Symphyta') in the Paleogene: revision, the new subfamily Cenocimbicinae, and new taxa from the Eocene Okanagan Highlands.

We erect the Cenocimbicinae, a new subfamily of Cimbicidae (Hymenoptera, Symphyta), restricted to the Selandian Menat Formation of France, the oldest occurrence of the family, and the Ypresian Okanagan Highlands of far-western North America. We describe new taxa from the Okanagan Highlands: Allenbycimbex morrisae gen. et sp.