Rocky An

All Publications

• Novel requirements for HAP2/GCS1-mediated gamete fusion in Tetrahymena. iScience Pinello, J. F., Loidl, J., Seltzer, E. S., Cassidy-Hanley, D., Kolbin, D., Abdelatif, A., Rey, F. A., An, R., Newberger, N. J., Bisharyan, Y., Papoyan, H., Byun, H., Aguilar, H. C., Lai, A. L., Freed, J. H., Maugel, T., Cole, E. S., Clark, T. G. 2024; 27 (6): 110146

  Abstract

  The ancestral gamete fusion protein, HAP2/GCS1, plays an essential role in fertilization in a broad range of taxa. To identify factors that may regulate HAP2/GCS1 activity, we screened mutants of the ciliate Tetrahymena thermophila for behaviors that mimic Δhap2/gcs1 knockout phenotypes in this species. Using this approach, we identified two new genes, GFU1 and GFU2, whose products are necessary for membrane pore formation following mating type recognition and adherence. GFU2 is predicted to be a single-pass transmembrane protein, while GFU1, though lacking obvious transmembrane domains, has the potential to interact directly with membrane phospholipids in the cytoplasm. Like Tetrahymena HAP2/GCS1, expression of GFU1 is required in both cells of a mating pair for efficient fusion to occur. To explain these bilateral requirements, we propose a model that invokes cooperativity between the fusion machinery on apposed membranes of mating cells and accounts for successful fertilization in Tetrahymena's multiple mating type system.

  View details for DOI 10.1016/j.isci.2024.110146

  View details for PubMedID 38904066

  View details for PubMedCentralID PMC11187246

• Influence of the spaceflight environment on macrophage lineages. NPJ microgravity An, R., Blackwell, V. K., Harandi, B., Gibbons, A. C., Siu, O., Irby, I., Rees, A., Cornejal, N., Sattler, K. M., Sheng, T., Syracuse, N. C., Loftus, D., Santa Maria, S. R., Cekanaviciute, E., Reinsch, S. S., Ray, H. E., Paul, A. M. 2024; 10 (1): 63

  Abstract

  Spaceflight and terrestrial spaceflight analogs can alter immune phenotypes. Macrophages are important immune cells that bridge the innate and adaptive immune systems and participate in immunoregulatory processes of homeostasis. Furthermore, macrophages are critically involved in initiating immunity, defending against injury and infection, and are also involved in immune resolution and wound healing. Heterogeneous populations of macrophage-type cells reside in many tissues and cause a variety of tissue-specific effects through direct or indirect interactions with other physiological systems, including the nervous and endocrine systems. It is vital to understand how macrophages respond to the unique environment of space to safeguard crew members with appropriate countermeasures for future missions in low Earth orbit and beyond. This review highlights current literature on macrophage responses to spaceflight and spaceflight analogs.

  View details for DOI 10.1038/s41526-023-00293-0

  View details for PubMedID 38862517

  View details for PubMedCentralID PMC11166655

• Neutrophils bearing adhesive polymer micropatches as a drug-free cancer immunotherapy. Nature biomedical engineering Kumbhojkar, N., Prakash, S., Fukuta, T., Adu-Berchie, K., Kapate, N., An, R., Darko, S., Chandran Suja, V., Park, K. S., Gottlieb, A. P., Bibbey, M. G., Mukherji, M., Wang, L. L., Mooney, D. J., Mitragotri, S. 2024

  Abstract

  Tumour-associated neutrophils can exert antitumour effects but can also assume a pro-tumoural phenotype in the immunosuppressive tumour microenvironment. Here we show that neutrophils can be polarized towards the antitumour phenotype by discoidal polymer micrometric 'patches' that adhere to the neutrophils' surfaces without being internalized. Intravenously administered micropatch-loaded neutrophils accumulated in the spleen and in tumour-draining lymph nodes, and activated splenic natural killer cells and T cells, increasing the accumulation of dendritic cells and natural killer cells. In mice bearing subcutaneous B16F10 tumours or orthotopic 4T1 tumours, intravenous injection of the micropatch-loaded neutrophils led to robust systemic immune responses, a reduction in tumour burden and improvements in survival rates. Micropatch-activated neutrophils combined with the checkpoint inhibitor anti-cytotoxic T-lymphocyte-associated protein 4 resulted in strong inhibition of the growth of B16F10 tumours, and in complete tumour regression in one-third of the treated mice. Micropatch-loaded neutrophils could provide a potent, scalable and drug-free approach for neutrophil-based cancer immunotherapy.

  View details for DOI 10.1038/s41551-024-01180-z

  View details for PubMedID 38424352

  View details for PubMedCentralID 8126820

• Single Cells Signal Non-self from Self via 'XOR' and 'NOT EQUALS' Logic in a Dimer of Dimers bioRxiv : the preprint server for biology An, R., Prakash, M. 2024; 10.01

  View details for DOI 10.1101/2024.10.01.616003

• MRTF may be the missing link in a multiscale mechanobiology approach toward macrophage dysfunction in space FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY An, R. 2022; 10

  View details for DOI 10.3389/fcell.2022.997365

  View details for Web of Science ID 000860781800001

  View details for PubMedID 36172272

• CAMDLES: CFD-DEM Simulation of Microbial Communities in Spaceflight and Artificial Microgravity LIFE-BASEL An, R., Lee, J. 2022; 12 (5)

  View details for DOI 10.3390/life12050660

  View details for Web of Science ID 000804910100001

  View details for PubMedID 35629329