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1. The BR-body proteome contains a complex network of protein-protein and protein-RNA interactions

   https://doi.org/10.1016/j.celrep.2023.113229  

   Nandana, Vidhyadhar; Rathnayaka-Mudiyanselage, Imalka W; Muthunayake, Nisansala S; Hatami, Ali; Mousseau, C Bruce; Ortiz-Rodríguez, Luis A; Vaishnav, Jamuna; Collins, Michael; Gega, Alisa; Mallikaarachchi, Kaveendya S; et al (October 2023, Cell Reports)
2. Targeted Protein Degradation through Recruitment of the CUL4 Complex Adaptor Protein DDB1

   https://doi.org/10.1021/acschembio.3c00487  

   Meyers, Margot; Cismoski, Sabine; Panidapu, Anoohya; Chie-Leon, Barbara; Nomura, Daniel K (January 2024, ACS Chemical Biology)
3. Protein encapsulation via polyelectrolyte complex coacervation: Protection against protein denaturation

   https://doi.org/10.1063/1.5040346  

   Zhao, Mengmeng; Zacharia, Nicole S. (October 2018, The Journal of Chemical Physics)
4. The effects of protein charge patterning on complex coacervation

   https://doi.org/10.1039/D1SM00543J  

   Zervoudis, Nicholas A.; Obermeyer, Allie C. (July 2021, Soft Matter)

   The complex coacervation of proteins with other macromolecules has applications in protein encapsulation and delivery and for determining the function of cellular coacervates. Theoretical or empirical predictions for protein coacervates would enable the design of these coacervates with tunable and predictable structure–function relationships; unfortunately, no such theories exist. To help establish predictive models, the impact of protein-specific parameters on complex coacervation were probed in this study. The complex coacervation of sequence-specific, polypeptide-tagged, GFP variants and a strong synthetic polyelectrolyte was used to evaluate the effects of protein charge patterning on phase behavior. Phase portraits for the protein coacervates demonstrated that charge patterning dictates the protein's binodal phase boundary. Protein concentrations over 100 mg mL −1 were achieved in the coacervate phase, with concentrations dependent on the tag polypeptide sequence covalently attached to the globular protein domain. In addition to shifting the binodal phase boundary, polypeptide charge patterning provided entropic advantages over isotropically patterned proteins. Together, these results show that modest changes of only a few amino acids in the tag polypeptide sequence alter the coacervation thermodynamics and can be used to tune the phase behavior of polypeptides or proteins of interest. 

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5. Structural basis of mitochondrial protein import by the TIM23 complex

   https://doi.org/10.1038/s41586-023-06239-6  

   Sim, Sue Im; Chen, Yuanyuan; Lynch, Diane L.; Gumbart, James C.; Park, Eunyong (June 2023, Nature)

   Mitochondria import nearly all of their approximately 1,000–2,000 constituent proteins from the cytosol across their double-membrane envelope1,2,3,4,5. Genetic and biochemical studies have shown that the conserved protein translocase, termed the TIM23 complex, mediates import of presequence-containing proteins (preproteins) into the mitochondrial matrix and inner membrane. Among about ten different subunits of the TIM23 complex, the essential multipass membrane protein Tim23, together with the evolutionarily related protein Tim17, has long been postulated to form a protein-conducting channel6,7,8,9,10,11. However, the mechanism by which these subunits form a translocation path in the membrane and enable the import process remains unclear due to a lack of structural information. Here we determined the cryo-electron microscopy structure of the core TIM23 complex (heterotrimeric Tim17–Tim23–Tim44) from Saccharomyces cerevisiae. Contrary to the prevailing model, Tim23 and Tim17 themselves do not form a water-filled channel, but instead have separate, lipid-exposed concave cavities that face in opposite directions. Our structural and biochemical analyses show that the cavity of Tim17, but not Tim23, forms the protein translocation path, whereas Tim23 probably has a structural role. The results further suggest that, during translocation of substrate polypeptides, the nonessential subunit Mgr2 seals the lateral opening of the Tim17 cavity to facilitate the translocation process. We propose a new model for the TIM23-mediated protein import and sorting mechanism, a central pathway in mitochondrial biogenesis. 

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