In This Issue
People & Ideas
A proteolytic cascade ensures that OMA1 cleaves and inactivates mitochondrial fusion protein OPA1 in times of stress, preventing damaged mitochondria from fusing with healthy organelles. (See also companion paper from Ehses et al. in this issue.)
PtdIns4P recognition by Vps74/GOLPH3 links PtdIns 4-kinase signaling to retrograde Golgi trafficking
Retention of Golgi-resident integral membrane proteins depends on the supply of PI(4)P.
Initial localization of ATM to double-strand breaks requires the MRE11–RAD50–NBS1 complex, but prolonged association requires ATM autophosphorylation.
The regenerative capacity of muscle is regulated by p38-γ, which phosphorylates MyoD and leads to formation of a complex that represses myogenin transcription.
A novel intermembrane space–targeting signal docks cysteines onto Mia40 during mitochondrial oxidative folding
A nine-residue intermembrane-targeting signal brings the active Cys of substrate proteins into contact with Mia40 oxidase for folding and import into mitochondria.
m-AAA proteases cleave OPA1 to ensure a balance of long and short OPA1 isoforms, whereas cleavage by OMA1 causes an accumulation of the short OPA1 variants. (See also companion paper from Head et al. in this issue.)
cIAPs keep RIP1 from getting to the DISC complex and complex II; when cIAPs are repressed, signaling is modulated by the cFLIP isoform.
Sorting of both soluble and integral membrane proteins is disrupted by loss of ADF/cofilin, suggesting that actin severing controls expansion of a sorting domain within the TGN.
Mechanical interactions between any two opposite-polarity motors are necessary and sufficient for bidirectional organelle transport in live cells.
The protein mutated in Huntington's disease is phosphorylated by the inflammatory kinase IKK, which promotes other post-translational modifications, and protein degradation.
Although FGF-2 causes the FGFR to be internalized and degraded, NCAM gets cells moving by stabilizing the receptor, promoting receptor recycling, and initiating a promigratory signaling cascade.
The Chlamydomonas reinhardtii BBSome is an IFT cargo required for export of specific signaling proteins from flagella
The Bardet-Biedl syndrome protein complex (BBSome) is a cargo adapter rather than an essential part of the intraflagellar transport (IFT) machinery.