Biology subjects

Griffith, W. P.

Publications and source records attributed to Griffith, W. P..

2 recordsLinked to original sources

bioRxiv2026

A lipid-binding protein in black-legged tick saliva selectively recognizes Borrelia burgdorferi lipids

A proteomic analysis of Ixodes scapularis nymph saliva identified 252 proteins, including six tubular lipid-binding proteins (TULIPs). Comparing nymphs fed on mice that were uninfected or infected with Borrelia burgdorferi, twelve salivary proteins showed significant differences in the amounts detected, including XP_040079658.2, which we refer to as TULIP2. Considering the known immunity-related functions of some TULIPs, we expressed and purified TULIP2 from Escherichia coli and analyzed its interaction with B. burgdorferi lipids. The purification of TULIP2 from E. coli presented many obstacles, due to insolubility, which is consistent with previous reports from studies of other TULIP family members. The binding results showed specificity for B. burgdorferi lipids, with evidence for cholesteryl {beta}-galactoside as a major binding target. Molecular modeling of TULIP2 did not show any strong lipid binding sites. We used molecular dynamics simulation of TULIP2 to explore its conformational landscape by thermal unfolding. The earliest unfolding intermediate opened a hydrophobic pocket to which cholesteryl {beta}-galactoside was predicted to bind strongly. We propose that a specific lipid bilayer interaction with TULIP2 triggers the opening of the ligand-binding site.

biochemistry↗

bioRxiv2023

Targeting APEX2 to the mRNA encoding fatty acid synthase β in yeast identifies proteins that bind and control its translational efficiency in the cell cycle

Profiling the repertoire of proteins associated with a given mRNA during the cell cycle is unstudied. Furthermore, it is much easier to ask and answer what mRNAs a specific protein might bind to than the other way around. Here, we implemented an RNA-centric proximity labeling technology at different points in the cell cycle in highly synchronous yeast cultures. To understand how the translation of FAS1, encoding fatty acid synthase, peaks late in the cell cycle, we identified proteins that bind the FAS1 transcript in a cell cycle-dependent manner. We used dCas13d-APEX2 fusions to target FAS1 and label nearby proteins, which were then identified by mass spectrometry. The glycolytic enzyme Tdh3p, a known RNA-binding protein, bound the FAS1 mRNA, and it was necessary for the increased Fas1p expression late in the cell cycle. Lastly, cells lacking Tdh3p had altered size homeostasis, consistent with delayed G1/S transition and exit from mitosis. These results point to unexpected connections between major metabolic pathways. They also underscore the role of mRNA-protein interactions for gene expression during cell division.

molecular biology↗