Author: Katharine White

New Graduate Students!

Warm welcome to our new Graduate students: Carlos Arias Matus & Ijeoma Asilebo & Châu Nguyen! Carlos is an IBMS graduate student and is studying how pHi drives 2D and 3D cell phenotype, IJ is an IBMS graduate student and is developing and applying new tools to manipulate single-cell pH. Châu is a Biochemistry Graduate student and joined us in December to study molecular mechanisms of pH-dependent cell division with a focus on pH-dependent protein degradation! Learn more about these awesome White Lab trainees by clicking “more info” on their bio entries here: https://sites.nd.edu/whitelab/lab-members/

Our work on spatiotemporal pHi dynamics during cell division is published in JCS!

Congrats to Julia Spear on her recent paper published in Journal of Cell Science! In the paper (Spear and White, 2023), Julia used timelapse confocal microscopy to measure intracellular pH in single dividing cells. She found that pHi oscillates during cell cycle progression and pHi dynamics correlate with cell cycle transitions. Julia next asked whether these pHi changes are sufficient to regulate cell cycle. She manipulated pHi and found that high pHi promotes S/G2 and G2/M transitions. She also found that G1 duration is sensitive to pHi with low pHi shortening G1 and high pHi elongating G1. These results indicate that finely titrated pHi regulation might be necessary for normal cell cycle progression and suggests a role for the increased pHi of cancer in driving cell cycle dysregulation.

Julia’s paper was highlighed in the JCS issue and she was selected for a “First Person” author feature!

Congrats to Caitlin and Leah on receiving Graduate Fellowships!

Leah Lund (Biochemistry Program) was recently awarded an Interdisciplinary Interface Training Project (IITP) graduate research fellowship from the Walther Cancer Foundation. Leah’s project will explore how molecular cues associated with mechanical stiffening of the tumor microenvironment contribute to or reinforce pH dysregulation in cancer. This project is performed in close collaboration with Donny Hanjaya Putra’s Lab in the Aerospace and Mechanical Engineering Department at Notre Dame.

Caitlin Donahue (Biochemistry Program) was recently awarded a graduate research fellowship from the Berthaiume Institute of Precision Health (BIPH) at Notre Dame. Caitlin’s project will be applying optogenetic tools to unravel roles for pHi in initiating and sustaining cancer cell behaviors.

Our work on spatiotemporal pHi manipulation is published in JACS!

Congrats to Caitlin Donahue and Michael Siroky on their recent paper published in JACS! Caitlin applied an optogenetic tool to raise pHi in single cells and study their responses. Undergraduate researcher Michael Siroky (ND ’22, Biochemistry & Neuroscience) worked closely with Caitlin on this project. See Publications for links to the paper!

In this video, first author Caitlin Donahue (Biochemistry Ph.D. Candidate) gives a “behind the scenes” on the paper, discussing key takeaways, surprising results, and next steps for the project!

Welcome Natalie and Chad!

Welcome to new White lab members! Natalie Waschbush is an undergraduate researcher at Notre Dame majoring in Biochemistry with a Neuroscience concentration. Our new technician Chad Sallaberry recently completed a master’s degree in Biochemistry at University of Colorado, Colorado Springs. Click the links to find out more about Natalie and Chad!

Welcome Brandon Czowski!

A warm welcome to Brandon Czowski!  Brandon is a biochemistry Ph.D. student who completed his B.S. in Biochemistry at Grand Valley State University. He’s ramping up a project on the more molecular arm of our lab, identifying molecular mechanisms of pH sensitive proteins. Learn more about Brandon here. And learn more about everyone in our growing lab here!