Verena Cmentowski @vcmentowski.bsky.social explored the mechanism that triggers dynein activation at kinetochores. CENP‑E facilitates the recruitment of dynein-dynactin and cofactors to kinetochores and regulates dynein motility. #SpindleCroatia2026
Tarun Kapoor developed a chemical genetic approach to analyze the functions of VPS4, a key protein required for nuclear envelope repair in human cells. Upon VPS4 inhibition, CHMP7 persists, and inner nuclear membrane defects form, leading to DNA damage. #SpindleCroatia2026
Julie Welburn @jwelburn.bsky.social showed the molecular basis for how PRC1 recruits CENP-E to the central spindle in anaphase. She also explored how drug binding varies with beta-tubulin isotypes, showing that human meiotic beta8-tubulin has a reduced sensitivity to nocodazole. #SpindleCroatia2026
Marin Barišić @barisiclab.bsky.social showed that acentrosomal cells often divide with uncongressed chromosomes. Lack of Aurora A at the poles of acentrosomal spindles is the main cause of chromosome missegregation. #SpindleCroatia2026
Ryota Uehara identified TPX2 as an adaptive factor for mitotic control after whole-genome duplication. TPX2 depletion caused multipolar spindles selectively in tetraploids. These cells required longer spindles to maintain their bipolarity than diploids. #SpindleCroatia2026
Véronique Marthiens asked how tissue properties affect mitosis. In the mammalian embryonic brain, biomechanical constraints enhance neural stem cell vulnerability by increasing microtubule growth and chromosome missegregation via cortical tension. #SpindleCroatia2026
Gerben Vader @vaderlab.bsky.social discussed mitotic vulnerabilities in chromosomally unstable cancer cells. KIF18A is a selective target causing chromosome misalignment and prolonged mitosis. “KIF18A-like” vulnerabilities are now being explored to expand anti-mitotic therapies. #SpindleCroatia2026
Beth Weaver explored the effect of microtubule-targeting agents on cancer cells and found that paclitaxel induces multipolar spindles without mitotic arrest in breast cancer. Pole focusing is a major mechanism of resistance. #SpindleCroatia2026
Geert Kops @kopslab.bsky.social showed beautiful fibrous coronas in bovine oocytes, which extend far beyond the kinetochores. The corona nucleates microtubules and promotes spindle assembly, but it may also be a liability if it completely encapsulates the chromosome. #SpindleCroatia2026
Ido Lavi developed a kinetic model in which RanGTP-regulated nucleators bind to microtubules and induce branching, while the microtubules polymerize at (+) ends and are transported poleward by Eg5. Multistep branching is important to get the right polarity. #SpindleCroatia2026
Martin Würtz @wuertzmartin.bsky.social explored augmin-microtubule interactions and showed that stable microtubule anchoring is mediated by the calponin homology domain of HAUS6, which determines the orientation of the augmin complex during microtubule branching. #SpindleCroatia2026
Ivana Gašić @ivanagasic.bsky.social showed that gamma-tubulin is regulated by the same machinery that regulates alpha-beta-tubulin levels, including TTC5, SCAPER, and CCR4-NOT. Disruption of this regulation compromises mitotic fidelity. #SpindleCroatia2026
Day3 of #SpindleCroatia2026! Arshad Desai @odlab.bsky.social showed that TRIM37 loss restores rapid spindle assembly in acentriolar cells by enabling the formation of pseudo-centrosomes. CDK5RAP2 was dispensable for this, but PLK4's CPB was required.
Kristjana Skendo from @labmeraldi.bsky.social showed that HURP, NuSAP, and Kid localize to bridging fibers in metaphase and, together with HAUS6/Augmin, act downstream of TPX2. Combined depletions lead to shorter overlaps, chromosome misalignment, and segregation errors. #SpindleCroatia2026
William Conway used cryo-electron tomography to map microtubule polarity in human metaphase spindles, and found that microtubules form locally antiparallel bundles with 8 nm wall-to-wall spacing. The spacing scaled inversely with microtubule density. #SpindleCroatia2026
Zachary Mullin-Bernstein from @dumontlabucsf.bsky.social used microneedle manipulation to pull on anaphase midzone bundles. The bundles locally transmit force to each other in the spindle’s short axis, and globally, leading to spindle shortening. #SpindleCroatia2026
Tomomi Kiyomitsu showed that short metaphase asters create a halo-like cytoplasmic concentration of dynein around aster tips in medaka early embryos. In anaphase, dynein relocates from the halo to growing asters, promoting successful cytokinesis. #SpindleCroatia2026
Andrew McAinsh showed that the first mitosis in human embryos is highly error-prone. MCAK agonist reduces multipolar divisions and those with multiple lagging chromosomes. Mosaicism is normal physiology in humans, and it may promote implantation. #SpindleCroatia2026
Tomoya Kitajima is designing different bead-based artificial kinetochores with the selected capabilities of microtubule attachment, force sensing, and spindle checkpoint activation in cells. They used NDC80-NUF2 beads as a tool to reduce errors in oocytes. #SpindleCroatia2026
Samya Aich asked what the minimal components for building a centriole are. He developed a synthetic phase-separated condensate platform, where Cep63 was sufficient for cartwheel assembly, and STIL overexpression led to procentriole assembly. #SpindleCroatia2026
Rita Tewari @ritatewari.bsky.social presented the unconventional mitosis in the malaria parasite. The Aurora-related kinase ARK1 is part of a highly divergent chromosomal passenger complex, whereas ARK2 interacts with EB1 and Myosin-K. #SpindleCroatia2026
Lovro Gudlin @lgudlin.bsky.social demonstrated a universal spindle scaling law, where metaphase plate width scales with genome size following a power law with an exponent of ~1/3. Chromosome crowding within the metaphase plate predicts the observed scaling. #SpindleCroatia2026
Dan Needleman showed that NDC80 binds noncooperatively to kinetochore microtubules in situ. The tension dependency of kinetochore microtubule detachments results from centromere-localized Aurora B phosphorylating NDC80 in a tension-dependent manner. #SpindleCroatia2026
Thomas Müller-Reichert showed that in C. elegans embryos, spindle length scales with cell size, but chromosome segregation dynamics remain constant. In RPE1 cells, 11-12 microtubules are attached end-on to each kinetochore, and monopolar spindles have a twist. #SpindleCroatia2026
Bonnibelle Leeds developed simulations of biorientation in yeast, which predict rapid biorientation. Error correction occurs due to four mechanisms: catch bond, Aurora, geometric bias, and direction-sensitive grip. #SpindleCroatia2026
Shane Fiorenza introduced a model which demonstrates that length-dependent regulation at both microtubule ends allows plus- and minus-end dynamics to mutually synchronize. This coordinated control of both microtubule ends regulates spindle length. #SpindleCroatia2026
Meredith Betterton showed that PRC1 accumulation at overlap edges drives PRC1 tilting, tighter spacing of the microtubules, and more resistance to sliding forces. Motor-crosslinker force balance sets the microtubule separation. #SpindleCroatia2026
Alex Mogilner made us rethink search-and-capture: Short microtubules at the kinetochore search for the long ones coming from the centrosome, helped by microtubule pivoting. Congression happens when sister kinetochores are pulled towards both poles. #SpindleCroatia2026
