Welcome to the Recombinant Antibody Network

@article{pmid42290195,

title = {Clarifying Frizzled 2 function in development through genetically validated mouse models},

author = {Megan N Michalski and Cassandra R Diegel and Zhendong A Zhong and Maddison E Marshall and Gabrielle E Foxa Wiartalla and Payton D Stevens and Kelly Suino-Powell and Levi L Blazer and Jarrett J Adams and Karsten Melcher and Sachdev S Sidhu and Stephane Angers and Bart O Williams},

doi = {10.1242/dmm.052410},

issn = {1754-8411},

year  = {2026},

date = {2026-07-01},

urldate = {2026-07-01},

journal = {Dis Model Mech},

volume = {19},

number = {7},

abstract = {Wnt receptors of the Frizzled (Fzd) family are widely considered to exhibit substantial functional redundancy, complicating efforts to therapeutically target individual receptors. Fzd2 was believed to be functionally redundant with Fzd1 and Fzd7, based on previously published global knockout mouse studies. By contrast, homozygosity for a Fzd2 global knockout mouse allele developed by the International Mouse Phenotype Consortium (IMPC) has been reported to cause embryonic lethality, suggesting that Fzd2 is critical for early embryonic development. If global deletion of Fzd2 leads to early lethality, conditional deletion models are necessary to identify tissue-specific phenotypes. We found that a previously published Fzd2 conditional deletion model does not eliminate Fzd2. We have generated a new conditional model to address the contradictory previous studies and allow tissue-specific studies of Fzd2. We successfully inserted two loxP sites around the Fzd2 gene and confirmed that subsequent Cre-mediated recombination creates a Fzd2 null allele. Global deletion of Fzd2 in this model does not cause embryonic lethality while limb-specific deletion causes limb shortening. This work supports the hypothesis that Fzd2 regulates limb development and emphasizes the importance of thoroughly validating newly generated mouse models.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid42538903,

title = {A  designed enzyme for photo-proximity labeling of E3 ligase neighborhoods in live cells},

author = {Nam Hyeong Kim and Zhi Lin and Sangwon Nam and Danielle L Swaney and Nevan Krogan and Yong Ho Kim and Michael J Therien and William F DeGrado and James A Wells},

doi = {10.64898/2026.07.22.739993},

issn = {2692-8205},

year  = {2026},

date = {2026-07-01},

urldate = {2026-07-01},

journal = {bioRxiv},

abstract = {Photocatalytic proximity labeling proteomics (photo-PLP) has emerged as a powerful technology for rapid capture of protein interactomes in situ. Typically, photo-PLP relies on chemical conjugation of the photocatalyst to the target of interest which creates practical challenges for derivatized photocatalyst synthesis and bioconjugation specificity. Integrating the precision of genetically encodable enzymes with the versatility of chemically defined photocatalysts provides a modular approach to further expand the scope of neighborhood mapping. Here, we present EYClamp, a  designed proximity labeling enzyme harnessing the off-the-shelf photocatalyst Eosin Y (EY) as a cofactor. Using a domain-swapped dimer architecture, we designed a scaffold that binds EY with high affinity (   = 10 nM) and lengthens its triplet excited-state lifetime by 29-fold. EYClamp enables efficient, multi-scale photocatalytic proximity labeling in live cells with aryl-diazirine-, aryl-azide- and phenol-biotin. We genetically fused EYClamp to a panel of six important E3 ligases. Using EYClamp, we identified over 1,500 candidate neighbors for KEAP1, MDM2, ASB7 and STUB1, providing a broad and unbiased view of these important neighborhoods. Critical functional networks were revealed including ASB7 engagement with HP1a/CUL5 complex for heterochromatin remodeling. Our EYClamp provides a genetically encodable "plug-and-play" solution for photo-PLP interactome discovery of the large family of E3 ligases and establishes domain-swapping as a promising strategy for  photoenzyme design.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{pmid42476294,

title = {Epitope-guided detection of a molecular glue-induced ternary complex using engineered synthetic antibody fragments},

author = {Kelly M O'Leary and Tomasz Slezak and Duc Anh Le and Anthony A Kossiakoff},

doi = {10.1016/j.jmb.2026.169953},

issn = {1089-8638},

year  = {2026},

date = {2026-07-01},

urldate = {2026-07-01},

journal = {J Mol Biol},

pages = {169953},

abstract = {Molecular glues represent a class of small molecules that enable the modulation of proteins lacking traditional ligand-binding pockets. A defining feature of molecular glues is their ability to bind cooperatively at weak or neomorphic protein-protein interfaces. Despite growing interest in these compounds, tools for selectively isolating native molecular glue-induced protein assemblies from heterogeneous populations in cells remain limited. Here, synthetic antibody fragment (Fab) reporters were generated by phage display to enable selective detection of the rapamycin-induced FKBP12-mTOR ternary complex as a model molecular glue-induced protein assembly. Crystallographic studies revealed the structural basis for three distinctive epitope recognition mechanisms to monitor the molecular glue activity of rapamycin using synthetic binders. Fab-1A and Fab-2C reported ternary complex formation with low to moderate precision by exploiting rapamycin-induced allosteric and interaction-gated epitopes, respectively. Fab-4R exhibited superior accuracy as a molecular glue reporter by sensing a rapamycin-gated junctional epitope that bridges the FKBP12-rapamycin-mTOR architecture. Structure-guided mutagenesis showed that the paratope of Fab-4R confers specificity for the ternary complex through hot spot interactions positioned directly across the conditional interface formed between FKBP12 and mTOR. Cell-based immunoprecipitation assays demonstrated that both Fab-4R and scFv-4R function as versatile molecular probes to report FKBP12-dependent mTOR inhibition by rapamycin with high fidelity and picomolar sensitivity. Taken together, these findings delineate the recognition properties for multiple antibody-based molecular glue reporters and highlight the versatility of synthetic binders for sensing conditionally formed epitopes within the proteome.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}