Response to Biophysical Journal comment to the editor by Skóra regarding the article entitled: Vast heterogeneity in cytoplasmic diffusion rates revealed by nanorheology and Doppelgänger simulations.

In a Comment to the Editor, Skóra raises a concern that the modeling framework implemented in Garner et al. (Biophysical Journal, 2023) neglects a potentially important term in the Brownian dynamics simulation of diffusion. Omission of this diffusivity gradient term may lead to an underestimation of the mean and overestimation of the variance of the cytoplasmic viscosity.

A unified model for the dynamics of ATP-independent ultrafast contraction.

In nature, several ciliated protists possess the remarkable ability to execute ultrafast motions using protein assemblies called myonemes, which contract in response to Ca ions. Existing theories, such as actomyosin contractility and macroscopic biomechanical latches, do not adequately describe these systems, necessitating development of models to understand their mechanisms. In this study, we image and quantitatively analyze the contractile kinematics observed in two ciliated protists ( sp.

Vast heterogeneity in cytoplasmic diffusion rates revealed by nanorheology and Doppelgänger simulations.

The cytoplasm is a complex, crowded, actively driven environment whose biophysical characteristics modulate critical cellular processes such as cytoskeletal dynamics, phase separation, and stem cell fate. Little is known about the variance in these cytoplasmic properties. Here, we employed particle-tracking nanorheology on genetically encoded multimeric 40 nm nanoparticles (GEMs) to measure diffusion within the cytoplasm of individual fission yeast (Schizosaccharomyces pombe) cellscells.

Physical properties of the cytoplasm modulate the rates of microtubule polymerization and depolymerization.

The cytoplasm is a crowded, visco-elastic environment whose physical properties change according to physiological or developmental states. How the physical properties of the cytoplasm impact cellular functions in vivo remains poorly understood. Here, we probe the effects of cytoplasmic concentration on microtubules by applying osmotic shifts to fission yeast, moss, and mammalian cells.

Plant and mouse EB1 proteins have opposite intrinsic properties on the dynamic instability of microtubules.

Objective: Most eukaryotic cells contain microtubule filaments, which play central roles in intra-cellular organization. However, microtubule networks have a wide variety of architectures from one cell type and organism to another. Nonetheless, the sequences of tubulins, of Microtubule Associated proteins (MAPs) and the structure of microtubules are usually well conserved throughout the evolution.

EB1 contributes to microtubule bundling and organization, along with root growth, in .

Microtubules are involved in plant development and adaptation to their environment, but the sustaining molecular mechanisms remain elusive. Microtubule-end-binding 1 (EB1) proteins participate in directional root growth in However, a connection to the underlying microtubule array has not been established yet. We show here that EB1 proteins contribute to the organization of cortical microtubules in growing epidermal plant cells, without significant modulation of microtubule dynamics.