Poe Dohn (crocusgender5)

Macroautophagy (hereafter referred to as autophagy) is a conserved process that promotes cellular homeostasis through the degradation of cytosolic components, also known as cargo. During autophagy, cargo is sequestered into double-membrane vesicles called autophagosomes, which are predominantly transported in the retrograde direction to the perinuclear region to fuse with lysosomes, thus ensuring cargo degradation.1 The mechanisms regulating directional autophagosomal transport remain unclear. The ATG8 family of proteins associates with autophagosome membranes2 and plays key roles in autophagy, including the movement of autophagosomes. This is achieved via the association of ATG8 with adaptor proteins like FYCO1, involved in the anterograde transport of autophagosomes toward the cell periphery.1,3-5 We previously reported that phosphorylation of LC3B/ATG8 on threonine 50 (LC3B-T50) by the Hippo kinase STK4/MST1 is required for autophagy through unknown mechanisms.6 Here, we show that STK4-mediated phosphorylation of LC3B-T50 reduces the binding of FYCO1 to LC3B. In turn, impairment of LC3B-T50 phosphorylation decreases starvation-induced perinuclear positioning of autophagosomes as well as their colocalization with lysosomes. Moreover, a significantly higher number of LC3B-T50A-positive autophagosomes undergo aberrant anterograde movement to axonal tips in mammalian neurons and toward the periphery of mammalian cells. Our data support a role of a nutrient-sensitive STK4-LC3B-FYCO1 axis in the regulation of the directional transport of autophagosomes, a key step of the autophagy process, via the post-translational modification of LC3B.The Silurian Period occupies a pivotal stage in the unfolding of key evolutionary events, including the rise of jawed vertebrates.1-4 However, the understanding of this early diversification is often hampered by the patchy nature of the Silurian fossil record,5 with the articulated specimens of jawed vertebrates only known in isolated localities, most notably Qujing, Yunnan, China.6-9 Here, we report a new Silurian maxillate placoderm, Bianchengichthys micros, from the Ludlow of Chongqing, with a near-complete dermatoskeleton preserved in articulation. Although geographically separated, the new taxon resembles the previously reported Qilinyu in possessing a unique combination of dermatoskeletal characters. However, the dermal bone of the mandible in Bianchengichthys unexpectedly differs from those in both Qilinyu and Entelognathus and displays a broad oral lamina carrying a line of tooth-like denticles, in addition to the marginal toothless flange. The external morphology of the pectoral fin is preserved and reveals an extensively scale-covered lobate part, flanked by a fringe of lepidotrichia-like aligned scales. The phylogenetic analysis reveals that Bianchengichthys is positioned immediately below Entelognathus plus modern gnathostomes. The discovery significantly widens the distribution of Silurian placoderm-grade gnathostomes in South China and provides a range of morphological disparity for the outgroup comparison to the earliest evolution of jaws, dentitions, and pectoral fins in modern gnathostomes. We also demonstrate that the previously reported Silurian placoderms from central Vietnam10 are maxillate placoderms close to Qilinyu, Silurolepis, and Bianchengichthys, corroborating the paleogeographic proximity between the Indochina and South China blocks during the Middle Paleozoic.11.Prior experience of a stimulus can inhibit subsequent acquisition or expression of a learned association of that stimulus. However, the neuronal manifestations of this learning effect, named latent inhibition (LI), are poorly understood. Here, we show that prior odor exposure can produce context-dependent LI of later appetitive olfactory memory performance in Drosophila. Odor pre-exposure forms a short-lived aversive memory whose lone expression lacks context-dependence. Acquisition of odor pre-exposure memo