Graded Wnt and JAK-STAT signals regulate the division rate, AP location and differentiation of Drosophila ovarian follicle stem cells to define a domain of stem cells maintained by population asymmetry.
A new family of sterol-specific lipid transfer proteins has been found that anchors in the endoplasmic reticulum; some of these proteins stretch across membrane contacts and mediate sterol traffic from the plasma membrane.
Cells accumulate damaged proteins during aging and, by compromising the function of chaperones in folding newly synthesized G1 cyclins, proteostasis breakdown inhibits cell-cycle entry and drives yeast cells into senescence.
The Drosophila response to injection of alpha-actinin reinforces the notion that exposure of cytoskeletal components acts as a sign of cell damage conserved throughout metazoan evolution.
Variability in bacterial transcription start site selection involves DNA “scrunching” and “anti-scrunching,” which may represent a general mechanism for start site selection in all organisms.
The small subunit ribosomal protein uS7/Rps5 interacts with translation initiation factor eIF2α to stabilize first the open, and then the closed conformation of the pre-initiation complex to promote accurate start codon selection in vivo.
RNA polymerase II generates numerous transcript isoforms, including transcripts initiating downstream of the START codon, that are efficiently degraded by the nonsense-mediated mRNA decay pathway.
Motivational coupling of action to reward and inhibition to punishment is subserved by dissociable learning and choice processes, and is modulated by dopamine/noradrenaline transporter blockade.
