bioRxiv Science⌕ Search

Biology subjects

Zarebidaki, F.

Publications and source records attributed to Zarebidaki, F..

3 recordsLinked to original sources

Taking shortcuts: Great for travel, but not for reproducible methods sections

Methods sections are often missing critical details needed to reproduce an experiment. Methodological shortcut citations, in which authors cite previous papers instead of describing the method in detail, may contribute to this problem. This meta-research study used three approaches to systematically examine the use of shortcut citations in neuroscience, biology and psychiatry. First, we examined papers to determine why authors use citations in the methods section and to assess how often shortcut citations were used. Common reasons for using citations in the methods section included explaining how something was done by citing a previous resource that used the method (methodological shortcut citation), giving credit or specifying what was used (who or what citation), and providing context or a justification (why citation). Next, we reviewed 15 papers to determine what can happen when readers follow shortcut citations to find methodological details. While shortcut citations can be used effectively, problems encountered included difficulty identifying or accessing the cited materials, missing or insufficient descriptions of the cited method, and chains of shortcut citations. Third, we examined journal policies. Fewer than one quarter of journals had policies describing how authors should report methods that have been described previously or asking authors to explain modifications of previously described methods. We propose that methodological shortcut citations should meet three criteria; cited resources should describe a method very similar to the authors method, provide enough detail to allow others to implement the method, and be open access. We outline actions that authors and journals can take to use shortcut citations responsibly, while fostering a culture of open and reproducible methods reporting.

neuroscience↗

Dynamin is primed at endocytic sites for ultrafast endocytosis

Dynamin mediates fission of vesicles from the plasma membrane during endocytosis. Typically, dynamin is recruited from the cytosol to endocytic sites, requiring seconds to tens of seconds. However, ultrafast endocytosis in neurons internalizes vesicles as quickly as 50 ms during synaptic vesicle recycling. Here we demonstrate that Dynamin 1 is pre-recruited to endocytic sites for ultrafast endocytosis. Specifically, Dynamin 1xA, a splice variant of Dynamin 1, interacts with Syndapin 1 to form molecular condensates on the plasma membrane when the proline-rich domain of this variant is dephosphorylated. When this domain is mutated to include phosphomimetic residues or Syndapin 1s dynamin-interacting domain is mutated, Dynamin 1xA becomes diffuse, and consequently, ultrafast endocytosis slows down by [~]100-fold. Mechanistically, Syndapin 1 acts as an adaptor by binding the plasma membrane and stores Dynamin 1xA at endocytic sites. This cache bypasses the recruitment step and accelerates endocytosis at synapses.

neuroscience↗

Complexin suppresses spontaneous exocytosis by capturing the membrane-proximal regions of VAMP2 and SNAP25

The neuronal protein complexin contains multiple domains that exert both clamping and facilitatory functions to tune spontaneous and action potential triggered synaptic release. We address the clamping mechanism and show that the accessory helix of complexin arrests the assembly of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex that forms the core machinery of intracellular membrane fusion. In a reconstituted fusion assay, site- and stage-specific photo-cross-linking reveals that prior to fusion the complexin accessory helix laterally binds the membrane-proximal C-terminal ends of SNAP25 and VAMP2. Corresponding complexin interface mutants selectively increase spontaneous release of neurotransmitter in living neurons, implying that the accessory helix suppresses final zippering/assembly of the SNARE four-helix bundle by restraining VAMP2 and SNAP25.

neuroscience↗