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New millipede specimens from the Paleozoic of Scotland are described, including Archidesmus macnicoli Peach, 1882, from the Lower Devonian (Lochkovian) Tillywhandland Quarry SSSI and three new taxa—Albadesmus almondi, Pneumodesmus newmani, and Cowiedesmus eroticopodus—from the mid Silurian (late Wenlock—early Ludlow) Cowie Formation at Cowie Harbour. Cowiedesmus eroticopodus new species is placed within the new Cowiedesmidae within the new order Cowiedesmida. Kampecaris tuberculata Brade-Birks from the Lower Devonian (Siegenian) of the Lanark Basin near Dunure is shown not to be a kampecarid myriapod, redescribed as Palaeodesmus tuberculata and placed order incertae sedis within Archipolypoda. Anthracodesmus macconochiei Peach is also redescribed and tentatively placed order incertae sedis within Archipolypoda. Archidesmus macnicoli, Albadesmus almondi, and Palaeodesmus tuberculata are each demonstrated to have broad sternites with laterally placed coxal sockets and paramedian pores containing paired valves. These pores are interpreted as having housed eversible vesicles. Some specimens of Archidesmus macnicoli and Cowiedesmus eroticopodus are male and have a pair of modified legs on trunk segment 8, identified as leg pairs 10 and 11, respectively. The presence of modified anterior legs restricted to segment 8 increases the range of variability known in modified appendage location in male millipedes and compounds existing uncertainty about using the presence of gonopods on trunk segment 7 as a synapomorphy of Helminthomorpha. An affinity between Archidesmida and Cowiedesmida is suggested based on possession of modified legs on segment 8 and Archidesmida + Cowiedesmida is placed along with Euphoberiida in Archipolypoda based on possession of free, broad sternites with bivalved paramedian pores and fused pleurotergites. The oldest known evidence of spiracles is demonstrated in Pneumodesmus newmani, proving that the oldest known millipedes were fully terrestrial.

The family of WD40-repeat (WDR) proteins is one of the largest in eukaryotes, but little is known about their function in brain development. Among 26 WDR genes assessed, we found 7 displaying a major impact in neuronal morphology when inactivated in mice. Remarkably, all seven genes showed corpus callosum defects, including thicker (Atg16l1, Coro1c, Dmxl2, and Herc1), thinner (Kif21b and Wdr89), or absent corpus callosum (Wdr47), revealing a common role for WDR genes in brain connectivity. We focused on the poorly studied WDR47 protein sharing structural homology with LIS1, which causes lissencephaly. In a dosage-dependent manner, mice lacking Wdr47 showed lethality, extensive fiber defects, microcephaly, thinner cortices, and sensory motor gating abnormalities. We showed that WDR47 shares functional characteristics with LIS1 and participates in key microtubule-mediated processes, including neural stem cell proliferation, radial migration, and growth cone dynamics. In absence of WDR47, the exhaustion of late cortical progenitors and the consequent decrease of neurogenesis together with the impaired survival of late-born neurons are likely yielding to the worsening of the microcephaly phenotype postnatally. Interestingly, the WDR47-specific C-terminal to LisH (CTLH) domain was associated with functions in autophagy described in mammals. Silencing WDR47 in hypothalamic GT1-7 neuronal cells and yeast models independently recapitulated these findings, showing conserved mechanisms. Finally, our data identified superior cervical ganglion-10 (SCG10) as an interacting partner of WDR47. Taken together, these results provide a starting point for studying the implications of WDR proteins in neuronal regulation of microtubules and autophagy.WD40-repeat proteins | corpus callosum agenesis | microcephaly | neurogenesis | autophagy T he function of WD40-repeat (WDR)-containing proteins, one of the largest eukaryotic protein families, is largely unknown. Their importance is, however, evident based on their highly conserved repeating units from bacteria to mammals (1), commonly made of seven repetitive blades of 40 amino acids that end with a tryptophan-aspartic acid dipeptide at the C terminus.As shown by crystallography studies, including the crystal structure of the beta gamma dimer of the G-protein transducin (2), a classical WDR protein, all WDR proteins are predicted to fold into a circularized beta-propeller structure, serving as a rigid platform (or scaffold) for protein-protein interactions by providing many stable and symmetrical surfaces (3, 4). One reason why WDR domains may have been less studied than other common domains, such as kinases or PDZ or SH3 domains (3), is that no WDR domain has yet been found with catalytic activity (3), but this does not mean that the scaffold domains are less important. To the contrary, their serving as a platform for multiple enzymatic reactions and signaling events is highly significant (5).In recent years, human genetic studies have also begun to recognize the importance of WDR gen...

In cats, TCC of the urinary bladder appears to be a rare and aggressive disease that is more prevalent in male cats and frequently develops at sites distant from the trigone (unlike TCC in dogs). Nevertheless, initial clinical signs of TCC in cats in this study were similar to those reported for affected dogs.

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