Interplay of self-organization of microtubule asters and crosslinking protein condensates.

The cytoskeleton is a major focus of physical studies to understand organization inside cells given its primary role in cell motility, cell division, and cell mechanics. Recently, protein condensation has been shown to be another major intracellular organizational strategy. Here, we report that the microtubule crosslinking proteins, MAP65-1 and PRC1, can form phase separated condensates at physiological salt and temperature without additional crowding agents in vitro.

Cytoskeletal regulation of a transcription factor by DNA mimicry via coiled-coil interactions.

A long-established strategy for transcription regulation is the tethering of transcription factors to cellular membranes. By contrast, the principal effectors of Hedgehog signalling, the GLI transcription factors, are regulated by microtubules in the primary cilium and the cytoplasm. How GLI is tethered to microtubules remains unclear.

Simultaneous Visualization of the Dynamics of Crosslinked and Single Microtubules In Vitro by TIRF Microscopy.

Microtubules are polymers of αβ-tubulin heterodimers that organize into distinct structures in cells. Microtubule-based architectures and networks often contain subsets of microtubule arrays that differ in their dynamic properties. For example, in dividing cells, stable bundles of crosslinked microtubules coexist in close proximity to dynamic non-crosslinked microtubules.

The tail wags the tubulin.

The C-terminal tail of tubulin influences microtubule assembly and stability. In this issue of Developmental Cell, Chen et al. combine in vitro experiments using recombinant tubulin with molecular dynamics simulations to provide molecular-level insights into the importance of α-tubulin tail and its post-translational modifications in microtubule assembly and stability.

Micron-scale geometrical features of microtubules as regulators of microtubule organization.

The organization of micron-sized, multi-microtubule arrays from individual microtubules is essential for diverse cellular functions. The microtubule polymer is largely viewed as a passive building block during the organization process. An exception is the 'tubulin code' where alterations to tubulin at the amino acid level can influence the activity of microtubule-associated proteins.

Differential regulation of single microtubules and bundles by a three-protein module.

A remarkable feature of the microtubule cytoskeleton is the coexistence of subpopulations having different dynamic properties. A prominent example is the anaphase spindle, where stable antiparallel bundles exist alongside dynamic microtubules and provide spatial cues for cytokinesis. How are the dynamics of spatially proximal arrays differentially regulated? We reconstitute a minimal system of three midzone proteins: microtubule-crosslinker PRC1 and its interactors CLASP1 and Kif4A, proteins that promote and suppress microtubule elongation, respectively.

Interplay between the Kinesin and Tubulin Mechanochemical Cycles Underlies Microtubule Tip Tracking by the Non-motile Ciliary Kinesin Kif7.

The correct localization of Hedgehog effectors to the tip of primary cilia is critical for proper signal transduction. The conserved non-motile kinesin Kif7 defines a "cilium-tip compartment" by localizing to the distal ends of axonemal microtubules. How Kif7 recognizes microtubule ends remains unknown.

Multiple oligomeric structures of a bacterial small heat shock protein.

Small heat shock proteins are ubiquitous molecular chaperones that form the first line of defence against the detrimental effects of cellular stress. Under conditions of stress they undergo drastic conformational rearrangements in order to bind to misfolded substrate proteins and prevent cellular protein aggregation. Owing to the dynamic nature of small heat shock protein oligomers, elucidating the structural basis of chaperone action and oligomerization still remains a challenge.

Characterization of rice small heat shock proteins targeted to different cellular organelles.

Small heat shock proteins (sHSPs) are a family of ATP-independent molecular chaperones which prevent cellular protein aggregation by binding to misfolded proteins. sHSPs form large oligomers that undergo drastic rearrangement/dissociation in order to execute their chaperone activity in protecting substrates from stress. Substrate-binding sites on sHSPs have been predominantly mapped on their intrinsically disordered N-terminal arms.

The influence of social networks on patients' attitudes toward type II diabetes.

Social networks are increasingly recognized as important determinants of many chronic diseases, yet little data exist regarding the influence of social networks on diabetes. We surveyed diabetic patients to determine how social networks affect their overall level of concern regarding diabetes and its complications. We adapted a previously published instrument and surveyed 240 diabetic patients at two primary care practices.

Dependence on emergency care among young adults in the United States.

Background: Young adults have a high prevalence of many preventable diseases and frequently lack a usual source of ambulatory care, yet little is known about their use of the emergency department.

Objective: To characterize care provided to young adults in the emergency department.

Design, Setting, And Participants: Cross-sectional analysis of visits from young adults age 20 to 29 presenting to emergency departments (N = 17,048) and outpatient departments (N = 14,443) in the National Hospital Ambulatory Medical Care Survey and National Ambulatory Medical Care Survey.