Joe Lannan

Joe Lannan

Biophysicist investigating the ultrafast contraction of Spirostomum ambiguum. PhD Candidate at NCSU and founder of Koinslot INC, a retro handheld gaming company.

Research

Education

Current Research

Investigation of Spirostomum ambiguum Cytoskeleton

My primary research focuses on investigating the cytoskeleton of Spirostomum ambiguum, often called “the fastest cell” due to its ability to contract its giant single-celled body in the blink of an eye. We found that its contraction is due to unique filaments known as the myoneme that allow it to contract without using traditional contractile machinery.

Spirostomum Contraction

Key Research Areas and Techniques:

Immuno-TEM imaging of Spirostomum Ambiguum

I performed advanced imaging using Immuno-TEM on the Spirostomum myoneme. This technique labeled centrin on the myoneme, confirming the presence of centrin in contracted and elongated cells and showing the structure of centrin-binding filaments in the myoneme. I further analyzed the structures of the uncontracted myoneme using AI-computer vision and graph theory analysis. This represented one of the first applications of immuno-TEM to this organism, requiring development of specialized protocols.

Confocal fluorescence imaging

Spirostomum presents many unique challenges for imaging, including its ability to rapidly contract and its sensitivity to chemicals. I’ve developed specialized methods for fixation and imaging, and applied various image analysis techniques using ImageJ and biophysical modeling to understand force generation of the Spirostomum cytoskeleton. Our techniques enable visualization of the myoneme network in both contracted and elongated states, providing critical insights into the contractile mechanism.

Multiscale computational modeling

I performed Molecular Dynamics simulations to analyze the effects of calcium binding to the myoneme. Preliminary results showed changes in persistence length of the myoneme as measured by correlation function of angles between residues of Sfi1. I also collaborated on models of the whole organism using energy minimization with the myoneme modeled as springs. This work bridges molecular-level events with organism-scale phenomena, providing a comprehensive understanding of the contraction mechanism.

Magnetic Tweezers Development

As part of our work on synthetic cytoskeletons, I’ve built and improved magnetic tweezers using multiple approaches:

This technology enables the application of controlled forces to cellular components, allowing us to probe mechanical properties and simulate cytoskeletal functions in synthetic systems.

Previous Research Experience

Condensed Matter Physics (NCSU, Dougherty Lab)

Worked with creating organic semiconductor devices using C8-BTBT, investigating surface effects on field effect transistors. Found that initial layers exhibited changes in crystal structure when grown on a surface versus in bulk.

Marine Biological Laboratory Projects

Imaging of archaea with SEM and ExM

Worked with Dyke Mullins lab to perform SEM and Expansion Microscopy imaging of understudied archaea. Produced some of the first SEM images published on these organisms.

Coordinated movement of snowflake yeast

Collaborated with Will Ratcliff’s lab to investigate genetically modified yeast selected for clumping and multicellular-like growth. Found that coordinated movement and organization could emerge from cell entanglement without direct selection.

Condensate separation of rRNA in the nucleus

Worked with Cliff Brangwynne’s lab to microinject labeled rRNA sequences and SARS-COVID RNA to investigate condensate dynamics of the nucleolus, showing sequence-dependent condensation importance for nucleolar organization.

Technical Expertise

Relevant Courses and Advanced Training