How motor proteins induce mechanical movement at the molecular level has been a focus of biophysicists for a long time. While the whole picture is yet to be completely revealed, recent developments in looking at nanometer‐scale movement with millisecond‐time resolution driven by single motors have revealed important new details about the moving step size and amount of force generated per molecule.

A variety of intracellular motile processes involve the directed movement of particles along microtubules, including organelle transport, endoplasmic reticulum extension, and movements in mitosis. Recently, a microtubule‐dependent motor protein, kinesin, was purified and was found to be present in a soluble form in a wide variety of organisms and tissues. Because microtubules provide polar pathways over long distances within cells, kinesin and the motors which move in the opposite direction to kinesin on microtubules provide a mechanism for directed communications within (...) cells. The possible roles of kinesin and other soluble microtubule‐dependent motors in intracellular motile functions are discussed in the light of recent studies of the reconstitution of organelle motility with isolated components. (shrink)

Recently discovered transcription‐independent features of p53 involve the choice of DNA damage repair pathway after PARylation, and p53's complex formation with phosphoinositide lipids, PI(4,5)P2. PARylation‐mediated rapid accumulation of p53 at DNA damage sites is linked to the recruitment of downstream repair factors and tumor suppression. This links p53's capability to sense damaged DNA in vitro and its relevant functions in cells. Further, PI(4,5)P2 rapidly accumulates at damage sites like p53 and complexes with p53, while it is required for ATR recruitment. (...) These findings help explain how p53 and PI(4,5)P2 maintain genome stability by directing DNA repair pathway choice. Additionally, there is a strong correlation between p53 sequence homology, genome mutation rates as well as lifespans across various mammalian species. Further investigation is required to better understand the connections between genome stability, tumor suppression, longevity and the transcriptional‐independent function of p53. (shrink)