Date: 1 February 2024 (Thursday)
Time: 5:00 pm – 6:00 pm
Venue: Cheung Kung Hai Lecture Theatre 1, G/F, William M.W. Mong Block, 21 Sassoon Road

5:00 p.m.

Presenter: Georgy SAPOZHNIKOV (PhD candidate)
Primary Supervisor: Dr. You-Qiang SONG
Presentation Title: Mechanosensing as a factor of aberrant apoptosis by Alzheimer’s disease
Abstract: By Alzheimer’s disease amyloid provokes a response from organism, among others, via Piezo1 and TRPV4 ion channels, sensitive to mechanical input. Aberrant apoptosis is a damage factor by AD. Until now, hardly any research links these aspects. We inspect the conflux of proteins and gene expression pathways of the two phenomena. Bayesian framework identified 8 gene drug targets differentially expressed within microglia in AD-affected brain, associated with mechanical response of tissue. We produced a whole-genome RNAseq analysis of HNRNP A1 knock-out mice models with AD, and obtained differentially expressed genes, for which Gene Ontology database analysis showed significant engagement in apoptotic processes. Another section was dedicated to caspase activation and mechanical forces in epithelium as a flexible model for manipulation. Our results validate the claim that aberrant apoptosis by Alzheimer’s disease is to a certain degree a consequence of mechanosensing properties of the tissues in which it takes place.

5:30 p.m.

Presenter: Marc Nicholas ZOPFI (MPhil candidate)
Primary Supervisor: Prof. Shih-Chieh TI
Presentation Title: The competition between the microtubule-stabilizing drug paclitaxel and tubulin acetyltransferases 
Abstract: Microtubules are polymers of α/β-tubulin heterodimers that act as major components of eukaryotic cytoskeletons. Catalysed by tubulin acetyltransferases, α-tubulin acetylation acts as a marker of stable cellular microtubules. While the sensitivity of cancer cells to the chemotherapeutic drug paclitaxel is correlated to tubulin acetylation level, the effect of paclitaxel on acetyltransferases is unclear. Our structural analysis of the acetyltransferases’ binding pattern shows enzymes sharing the same tubulin binding site as paclitaxel. In this study, we generated and purified recombinant tubulin and tubulin acetyltransferases for in vitro reconstitution assays. Fluorescent microscopy is used to visualize changes in the acetyltransferases’ binding affinity in the presence of paclitaxel. Furthermore, cancer cell-based assays are performed to assess the level of acetyltransferase expression and tubulin acetylation. Our study reveals that acetyltransferases and paclitaxel compete for the taxane-binding site on β-tubulin, providing the molecular basis for future dissection of the biological functions of tubulin acetyltransferases.

ALL ARE WELCOME

Should you have any enquiries, please feel free to contact Jerry Siu at 3917 6912.