Biology subjects

Combs, C.

Publications and source records attributed to Combs, C..

3 recordsLinked to original sources

bioRxiv2022

Mechanical activation of mitochondrial energy metabolism during cell differentiation

In multicellular lives, differentiation of many types of stem and progenitor cells is often accompanied by a metabolic transition from glycolysis to mitochondrial oxidative phosphorylation. The mechanisms driving this metabolic transition in vivo are largely unknown. Here, we show that, during differentiation of the Drosophila female germline cyst, the surrounding somatic cells compress the cyst and increase the tension of cyst cells membranes. Transmembrane channel-like, an evolutionarily conserved ion channel involved in mechanosensation, maintains cytosolic Ca2+ levels in compressed differentiating cysts. Cytosolic Ca2+ induces transcriptional activation of oxidative phosphorylation through a CaMKI-Fray-JNK signaling relay. Our findings demonstrate a molecular link between cell mechanics and mitochondrial energy metabolism, with implications in other developmentally orchestrated metabolic transitions in mammals. One-Sentence SummaryMechanical forces from the surrounding tissue activate mitochondrial energy metabolism in differentiating cells in vivo.

cell biology↗

bioRxiv2022

Pericentrin is a Kinesin-1 Activator that Drives Centriole Motility

Centrosome positioning is essential for their function. Typically, centrosomes are transported to various cellular locations through the interaction of centrosome nucleated microtubules with motor proteins. However, it remains unknown how centrioles migrate in cellular contexts in which centrioles do not nucleate microtubules. Here, we demonstrate that during interphase inactive centrioles move directly along the non-centrosomal microtubule network as cargo for the motor protein Kinesin-1. We identify Pericentrin-Like-Protein (PLP) as a novel Kinesin-1 interacting molecule essential for centriole motility. PLP directly interacts with the cargo binding domain of Kinesin-1 and they comigrate on microtubules in vitro. Finally, we demonstrate that PLP-Kinesin-1 dependent transport is essential for centrosome asymmetry age-dependent centrosome inheritance in asymmetric stem cell division.

cell biology↗

bioRxiv2021

Multiview super-resolution microscopy

We enhance the performance of confocal microscopy over imaging scales spanning tens of nanometers to millimeters in space and milliseconds to hours in time, improving volumetric resolution more than 10-fold while simultaneously reducing phototoxicity. We achieve these gains via an integrated, four-pronged approach: 1) developing compact line-scanners that enable sensitive, rapid, diffraction-limited imaging over large areas; 2) combining line-scanning with multiview imaging, developing reconstruction algorithms that improve resolution isotropy and recover signal otherwise lost to scattering; 3) adapting techniques from structured illumination microscopy, achieving super-resolution imaging in densely labeled, thick samples; 4) synergizing deep learning with these advances, further improving imaging speed, resolution and duration. We demonstrate these capabilities on more than twenty distinct fixed and live samples, including protein distributions in single cells; nuclei and developing neurons in Caenorhabditis elegans embryos, larvae, and adults; myoblasts in Drosophila wing imaginal disks; and mouse renal, esophageal, cardiac, and brain tissues.

bioengineering↗