Biochemistry

The TTLL10 polyglycylase is stimulated by tubulin glutamylation and inhibited by polyglycylation

1. Steven W Cummings
2. Yan Li
3. Jeffrey O Spector
4. Christopher Kim
5. Antonina Roll-Mecak

• Curated by eLife

  eLife Assessment

  In their study, Cummings et al. provide a valuable advance in understanding the hierarchical regulation of tubulin polyglycylation, demonstrating that TTLL8 initiates monoglycylation which is a prerequisite for TTLL10-mediated polyglycylation. The evidence supporting these mechanistic insights is solid, relying on a compelling combination of purified biochemical assays, mass spectrometry, and microscopy. The work is further valued for revealing an unexpected crosstalk between polyglycylation and polyglutamylation that ensures a balanced post-translational modification landscape for proper cilia function.

Reviewed by eLife

RamanMAE: Masked Autoencoders Enable Efficient Molecular Imaging by Learning Biologically Meaningful Spectral Representations

1. Santosh Kumar Paidi
2. Parul Maheshwari

Reviewed by Arcadia Science

Blue-shifted ancyromonad channelrhodopsins for multiplex optogenetics

1. Elena G Govorunova
2. Oleg A Sineshchekov
3. Hai Li
4. Yueyang Gou
5. Hongmei Chen
6. Shuyuan Yang
7. Yumei Wang
8. Stephen Mitchell
9. Alyssa Palmateer
10. Leonid S Brown
11. François St-Pierre
12. Mingshan Xue
13. John L Spudich

• Curated by eLife

  eLife Assessment

  This important study describes newly identified light-gated ion channel homologs (channelrhodopsins, ChRs) in several protist species, with a primary focus on the biophysical characterization of ChRs of ancyromonads. The authors employed a powerful combination of bioinformatics, manual and automated patch-clamp electrophysiology, absorption spectroscopy, and flash photolysis. Additionally, they evaluated the applicability of the newly discovered anion-conducting ChRs in cortical neurons of mouse brain slices and in living C. elegans worms. The evidence supporting most of the claims is compelling, and this work will be of interest to the microbial rhodopsin community and neuro- and cardioscientists utilizing optogenetics in their research.

Reviewed by eLife

Dock-and-lock binding of SxIP ligands is required for stable and selective EB1 interactions

1. Teresa Almeida
2. Eleanor Hargreaves
3. Tobias Zech
4. Igor Barsukov

• Curated by eLife

  eLife Assessment

  This study provides important insights into how the EBH domain of microtubule end-binding protein 1 (EB1) interacts with SxIP peptides derived from the MACF plus-end tracking protein. The revised manuscript includes convincing ITC and NMR experiments that clarify the role of flanking residues and address the influence of dimerization and cooperativity on binding. While some mechanistic aspects remain difficult to resolve experimentally, the data and analysis now more clearly justify the proposed "dock-and-lock" model and its interpretive value. This work will be of interest to structural biologists and biophysicists studying microtubule-associated protein interactions.

Reviewed by eLife

Tentative evidence that aging is caused by a small number of interacting processes

1. Axel Kowald
2. Thomas B L Kirkwood

Reviewed by PREreview

Multiple modes of cholesterol translocation in the human Smoothened receptor

1. Prateek D Bansal
2. Maia Kinnebrew
3. Rajat Rohatgi
4. Diwakar Shukla

• Curated by eLife

  eLife Assessment

  In this useful study, the authors conducted a set of computational and experimental investigations of the mechanism of cholesterol transport in the smoothened (SMO) protein. The computational component integrated multiple state-of-the-art approaches such as adaptive sampling, free energy simulations, and Markov state modeling, providing support for the proposed mechanistic model, which is also consistent with the experimental mutagenesis data. However, substantial revisions are needed for the discussion of the computational results and interpretation of the literature to provide a more balanced and accurate perspective on cholesterol-mediated SMO regulation. In the current form, therefore, the strength of evidence of the study is considered incomplete.

Reviewed by eLife

Dynamic assembly of malate dehydrogenase-citrate synthase multienzyme complex in the mitochondria

1. Joy Omini
2. Inga Krassovskaya
3. Taiwo Dele-Osibanjo
4. Connor Pedersen
5. Toshihiro Obata

• Curated by eLife

  eLife Assessment

  This study reports a dynamic association/dissociation between malate dehydrogenase (MDH1) and citrate synthase (CIT1) in Saccharomyces cerevisiae under different metabolic conditions that control TCA pathway flux rate. The research question is timely, the use of the NanoBiT split-luciferase system to monitor protein-protein interactions is innovative, and the significance of the findings is valuable. However, the strength of evidence needed to support the conclusions was found to be incomplete based on a lack of critical control and mechanistic experiments.

Reviewed by eLife

Systematic characterization of site-specific proline hydroxylation using hydrophilic interaction chromatography and mass spectrometry

1. Hao Jiang
2. Jimena Druker
3. James W Wilson
4. Dalila Bensaddek
5. Jason R Swedlow
6. Sonia Rocha
7. Angus I Lamond

• Curated by eLife

  eLife Assessment

  The study presents a valuable resource of proline hydroxylation proteins for molecular biology studies in oxygen-sensing and cell signaling with the characterization of Repo-man proline hydroxylation site. The evidence supporting the claim of the authors is solid, although further clarification of the overall efficiency of the HILIC analysis, the specificity/sensitivity of immonium ion analysis, as well as quantification of proline hydroxylation identifications will be helpful. The work will be of interest to researchers studying post-translational modification, oxygen sensing, and cell signaling.

Reviewed by eLife

MCAK recognizes the nucleotide-dependent feature at growing microtubule ends

1. Wei Chen
2. Yin-Long Song
3. Jian-Feng He
4. Xin Liang

• Curated by eLife

  eLife Assessment

  This work presents valuable new information on the microtubule-binding mode of the microtubule kinesin-13, MCAK, the authors use quantitative single-molecule studies to propose that MCAK preferentially binds to a GDP-Pi-tubulin portion of the microtubule end. However, the evidence provided to support this claim remains incomplete and would benefit from more rigorous methodology particularly the diffraction limited experiments do not provide sufficient spatial resolution to support the authors' conclusions. In addition, a more through discussion of the existing literature would further strengthen the manuscript.

Reviewed by eLife

Coupled equilibria of dimerization and lipid binding modulate SARS Cov 2 Orf9b interactions and interferon response

1. CJ San Felipe
2. Jyoti Batra
3. Monita Muralidharan
4. Shivali Malpotra
5. Durga Anand
6. Rachel Bauer
7. Kliment A Verba
8. Danielle L Swaney
9. Nevan J Krogan
10. Michael Grabe
11. James S Fraser

• Curated by eLife

  eLife Assessment

  This fundamental study demonstrates that lipid binding can regulate the dimerization state of the SARS-CoV2 Orf9b protein. The data from biophysical and cellular experiments along with mathematical modeling are compelling. This paper is broadly relevant to those studying coupled equilibria across all aspects of biology.

Reviewed by eLife