Sudeepa Rajan, Jimok Yoon, Heng Wu, Raju Baskar, Roman Aguirre, Jonathan R. Terman, Emil Reisler
Why F-actin is often simultaneously bundled together with multiple different bundling proteins and how these complex stable F-actin bundles undergo spatiotemporally targeted disassembly to drive cellular remodeling are poorly understood. Rajan et al. identify mechanisms for assembling and disassembling complex networks of multi-protein–bundled F-actin, including a synergism between different bundlers and disassemblers in these processes.
Rachel S. Keegan, Dina Malkeyeva, Meg B. Weever, Elaine M. Dunleavy
In the fruit fly, the centromeric histone CENP-A is assembled in two phases: prophase of meiosis I and postmeiosis II. Keegan et al. show that a new pool of constitutive centromere protein CENP-C is loaded at the centromere in prophase of meiosis I. This pool is critical for kinetochore assembly and meiotic chromosome segregation.
Alba Muniesa-Vargas, Cristina Ribeiro-Silva, Carlota Davó-Martínez, Anja Raams, Bart Geverts, Jacinta van de Grint, Maroussia Ganpat, Karen L. Thijssen, Joris Pothof, Adriaan B. Houtsmuller, Arjan F. Theil, Wim Vermeulen, Hannes Lans
Muniesa-Vargas et al. use live-cell imaging to uncover how XPG activity is dynamically controlled during nucleotide excision repair. They show that TFIIH and XPA promote its recruitment, while incision by XPF and XPG, as well as the arrival of PCNA and DNA processing by EXO1, promote its release.
Nicala Jenkins, Zainab Adamji, Maria R. Narciso, Nourhan R. Almasri, Sharifa Lomiyev, Roberto J. Botelho
Long associated with the regulation of the endolysosomal pathway, the authors show that the PIKfyve lipid kinase extends its sphere of influence to modulate the architecture and dynamics of the ER by balancing phosphoinositide species at their inter-organellar sites.
Shiying Huang, Yeun Ju Kim, Xiaofu Cao, Timothy W. Bumpus, Mira Sohn, Matthew Tyler Menold, Ryan K. Dale, Jin Joo Kang, Saori Uematsu, Shagun Gupta, Shu-Bing Qian, Haiyuan Yu, Tamas Balla, Jeremy M. Baskin
Plasma membrane identity depends on tight control of anionic lipid composition, but how cells sense and correct imbalances remains poorly understood. Huang et al. find that PI4P depletion lowers phosphatidylserine and upregulates RhoB, driving phospholipase D-mediated phosphatidic acid synthesis and actin remodeling to preserve membrane structure and identity.
Wang et al. show that deletion of the nonhelical tailpiece (NHT) in myosin-II results in enlarged bipolar filaments with reduced bare zones, decreased disassembly, and impaired cell migration, providing mechanistic insight into disease-associated stop-codon mutations in the NHT of myosin-IIA.
Honghai Liu, Niyatie Ammanamanchi, Jocelyn D. Mich-Basso, Brian K. Panama, Yao Li, Winston Huang, Dena Almeida, Christopher M. Lewarchik, Brendan Lo, Yijen Wu, Michael Gotthardt, Michael I. Kotlikoff, Wolfgang Baehr, Randall Rasmusson, Guy Salama, Bernhard Kühn
Cardiomyocyte contractions require calcium transients. Liu et al. show that mitotic cardiomyocytes suppress calcium transients and remodel the sarcoplasmic reticulum/endoplasmic reticulum. These changes are required for cardiomyocyte division and identify a link between calcium signaling and cytokinesis in cardiomyocytes.
Andreas Boland previews work from Williams and colleagues, which shows that chromosome segregation is independent of separase-mediated feedback and that synchrony is affected by a small number of stochastic effects.
Ray and Singhvi discuss recent work from Sakers and colleagues, showing that Nedd4l/HECT E3 ligase ubiquitination of astrocyte NL2 promotes astrocyte morphogenesis.
Nicola Diny previews a study from Petrova et al., which reveals that eosinophils drive a developmental program for postnatal intestinal remodeling and maturation.
