Large multiprotein complexes perform many essential functions in eukaryotic cells. My lab purifies, assays and determines structures of these macromolecular machines to understand their mechanisms. This often involves a combination of several techniques or the development new methods.

Two possible projects are available in my group. The first project will address multiprotein complexes that regulate mRNA poly(A) tails. Almost every eukaryotic mRNA has a poly(A) tail at its 3ʹ-end.  Poly(A) tails are added in the nucleus after endonucleolytic cleavage of the pre-mRNA and are required for export of mRNAs from the nucleus, for efficient translation and for mRNA stability. In the cytoplasm, poly(A) tails are shortened in a regulated manner to promote mRNA decay. We are studying the protein machineries that add and remove poly(A) tails. We aim to understand how these complexes are regulated, how they recognise mRNA, and the specific roles of subunits.

The alternative project will address DNA repair mechanisms, specifically, the cellular response to DNA crosslinks and replication stress. The Fanconi Anaemia (FA) pathway is at the centre of DNA crosslink repair and involves a large multiprotein E3 ubiquitin ligase and a DNA clamp. Deregulation of this pathway can lead to human disease. We aim to understand the molecular mechanisms of the FA pathway.

A wide range of techniques are employed by the group, including cryo-electron microscopy (cryo-EM), x-ray crystallography, single molecule studies, genetics, biophysics and biochemical assays.

Please contact me for more information and to discuss projects.

References

Roles of mRNA poly(A) tails in regulation of eukaryotic gene expression.
Passmore LA, Coller J
Nat Rev Mol Cell Biol 23(2): 93-106 (2022)

3′-End Processing of Eukaryotic mRNA: Machinery, Regulation, and Impact on Gene Expression
Boreikaitė V, Passmore LA
Annual Review of Biochemistry 92(1): 199-225 (2023)

Phosphorylation-dependent tuning of mRNA deadenylation rates
Stowell JAW, Yu CWH, Chen ZA, Lee G, Morgan T, Sinn L, Agnello S, O’Reilly FJ, Rappsilber J, Freund SMV, Passmore LA
bioRxiv: (2024) preprint

FANCD2–FANCI surveys DNA and recognizes double- to single-stranded junctions
Alcón P, Kaczmarczyk AP, Ray KK, Liolios T, Guilbaud G, Sijacki T, Shen Y, McLaughlin SH, Sale JE, Knipscheer P, Rueda DS, Passmore LA
Nature 632(8027): 1165-1173 (2024)

A direct interaction between CPF and RNA Pol II links RNA 3′ end processing to transcription.
Carminati M, Rodríguez-Molina JB, Manav MC, Bellini D, Passmore LA
Mol Cell 83(24): 4461-4478.e13 (2023)

Mpe1 senses the binding of pre-mRNA and controls 3′ end processing by CPF.
Rodríguez-Molina JB, O’Reilly FJ, Fagarasan H, Sheekey E, Maslen S, Skehel JM, Rappsilber J, Passmore LA
Mol Cell 82(13): 2490-2504.e12 (2022)