Backstepping Mechanism of Kinesin-1.

Kinesin-1 is an ATP-driven molecular motor that transports cellular cargo along microtubules. At low loads, kinesin-1 almost always steps forward, toward microtubule plus ends, but at higher loads, it can also step backward. Backsteps are usually 8 nm but can be larger.

Tumor protein D54 defines a new class of intracellular transport vesicles.

Transport of proteins and lipids from one membrane compartment to another is via intracellular vesicles. We investigated the function of tumor protein D54 (TPD54/TPD52L2) and found that TPD54 was involved in multiple membrane trafficking pathways: anterograde traffic, recycling, and Golgi integrity. To understand how TPD54 controls these diverse functions, we used an inducible method to reroute TPD54 to mitochondria.

FAST in the deployed military setting.

Introduction: Focused assessment with sonography in trauma (FAST) is historically an effective method of assessing the patient in the trauma bay in order to aid decision-making and optimise patient outcomes. However, in the UK civilian practice, the use of FAST may decline given a recent change in National Institute for Health and Care Excellence guidance as a result of improvement in CT availability and resuscitation techniques.

Method: In the Role 3 Medical Treatment Facility, Camp Bastion, 187 patients with trauma who received FAST in the trauma bay in 2014 were reviewed to determine the accuracy of FAST in the deployed environment.

Curvature-induced expulsion of actomyosin bundles during cytokinetic ring contraction.

Many eukaryotes assemble a ring-shaped actomyosin network that contracts to drive cytokinesis. Unlike actomyosin in sarcomeres, which cycles through contraction and relaxation, the cytokinetic ring disassembles during contraction through an unknown mechanism. Here we find in and that, during actomyosin ring contraction, actin filaments associated with actomyosin rings are expelled as micron-scale bundles containing multiple actomyosin ring proteins.

Dyslipidaemia and the military patient.

Dyslipidaemias refer to abnormal levels of circulating lipids and high cholesterol and is related to cardiovascular death. This paper examines the types and prevalence of dyslipidaemia with specific reference to a military population and describes who to target in screening strategies used to detect people with abnormal lipid profiles. The diagnostic limits for a diagnosis of dyslipidaemia are explored.

The Kinesin-12 Kif15 is a processive track-switching tetramer.

Kinesin-12 motors are a little studied branch of the kinesin superfamily with the human protein (Kif15) implicated in spindle mechanics and chromosome movement. In this study, we reconstitute full-length hKif15 and its microtubule-targeting factor hTpx2 in vitro to gain insight into the motors mode of operation. We reveal that hKif15 is a plus-end-directed processive homotetramer that can step against loads of up to 3.

An unmet actin requirement explains the mitotic inhibition of clathrin-mediated endocytosis.

Clathrin-mediated endocytosis (CME) is the major internalisation route for many different receptor types in mammalian cells. CME is shut down during early mitosis, but the mechanism of this inhibition is unclear. In this study, we show that the mitotic shutdown is due to an unmet requirement for actin in CME.

Kinesin backsteps.

Kinesin-1 is a walking machine that takes ~8 nm steps along microtubules. Some aspects of the molecular mechanism of walking are now clear, but many are not. In the present paper, we discuss currently controversial points, focusing on the pathways by which kinesin takes occasional backsteps.

Kinesin's moonwalk.

Kinesin-1 is a single-molecule walking machine, driven by ATP turnover. Recent optical trapping experiments show that pulling backwards on a walking kinesin-1 molecule causes the mechanical walking action to reverse, while the coupled chemical cycle of ATP turnover continues, apparently, to run forwards -- kinesin can moonwalk. Individual forward- and back-steps are fast, and each appears to be a single event, complete in a few tens of microseconds, with no substeps.