M. C. Johnson

Disulfide constrained Fabs overcome target size limitation for high-resolution single-particle cryo-EM

This paper introduces Rigid-Fabs, disulfide-constrained antibody fragments that enable high-resolution cryo-EM structures of small proteins by overcoming size limitations.

Convergent evolution in SARS-CoV-2 Spike creates a variant soup that causes new COVID-19 waves.

This paper identifies convergent evolution in SARS-CoV-2 Spike protein mutations across variants, leading to increased viral fitness and immune escape, and suggests rethinking antibody therapies.

Translation-dependent downregulation of Cas12a mRNA by an anti-CRISPR protein

This study shows that AcrVA2 inhibits Cas12a mRNA translation, reducing its anti-phage activity and enabling specific inhibition of Cas12a orthologs.

IMPDH1 retinal variants control filament architecture to tune allosteric regulation

The paper shows IMPDH1 retinal variants form different filaments that affect GTP regulation, with disease mutations disrupting or not affecting this regulation.

Novel compound inhibitors of HIV-1NL4-3 Vpu

This study identifies two compounds that inhibit HIV-1NL4-3 Vpu activity but are strain-specific.

An infectious Rous Sarcoma Virus Gag mutant that is defective in nuclear cycling

This paper describes a Rous Sarcoma Virus Gag mutant defective in nuclear cycling that is replication competent but with slower spread compared to wild-type virus.

Assembly of higher-order SMN oligomers is essential for metazoan viability and requires an exposed structural motif present in the YG zipper dimer

This study identifies a structural motif in the SMN YG box essential for higher-order oligomerization, which is critical for viability and linked to SMA in animal models.

An open interface in the pre-80S ribosome coordinated by ribosome assembly factors Tsr1 and Dim1 enables temporal regulation of Fap7

The paper determines the structure of an 80S-like ribosome assembly intermediate, revealing how Tsr1 and Dim1 coordinate to regulate Fap7 and enable quality control during ribosome maturation.

Checkpoint inhibition of origin firing prevents inappropriate replication outside of S-phase

This study shows that the S-phase checkpoint, via Rad53 kinase, inhibits replication initiation factors beyond S-phase, preventing re-replication and inappropriate gene amplification in G2/M and G1 phases.

Optimized pseudotyping conditions for the SARS-COV2 Spike glycoprotein

This paper optimizes conditions for generating SARS-CoV-2 Spike pseudotyped viral particles, achieving high titers and demonstrating their utility in detecting neutralizing antibodies in COVID-19 patient plasma.

Inositol hexakisphosphate (IP6) and inositol pentakisphosphate (IP5) are required for viral particle release of retroviruses belonging to the primate lentivirus genus

This study shows that IP6 and IP5 are essential for HIV-1 and SIV-mac particle release, but not for other retroviruses, and are required in producer cells, not target cells.

T Cell Activation Triggers Reversible Inosine-5’-Monophosphate Dehydrogenase Assembly

This study shows T cell activation leads to reversible IMPDH assembly into filaments, regulated by mTOR and STIM1, with implications for guanine nucleotide biosynthesis and T cell proliferation.

IMPDH polymers accommodate both catalytically active and inactive conformations

The paper investigates IMPDH polymerization and finds that polymerized and non-assembled forms have comparable catalytic activity, with substrate and nucleotide availability affecting filament conformation.