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Rice, P.

Publications and source records attributed to Rice, P..

2 recordsLinked to original sources

Mobile genetic element-encoded putative DNA primases composed of A-family polymerase - SSB pairs

1Mobile genetic elements can encode a wide variety of genes that support their own stability and mobility as well as genes that provide accessory functions to their hosts. Such genes can be adopted from host chromosomes and can be exchanged with other mobile elements. Due to their accessory nature, the evolutionary trajectories of these genes can differ from those of essential host genes. The mobilome therefore provides a rich source of genetic innovation. We previously described a new type of primase encoded by S. aureus SCCmec elements that is composed of an A-family polymerase catalytic domain in complex with a small second protein that confers single-stranded DNA binding. Here we use new structure prediction methods in conjunction with sequence database searches to show that related primases are widespread among putative mobile genetic elements in the Firmicutes. Structure predictions show that the second protein adopts an OB fold (common among single-stranded DNA binding (SSB) proteins) and these predictions were far more powerful than simple sequence comparisons in identifying its homologs. The protein-protein interaction surface varies among these polymerase - SSB complexes and appears to have arisen repeatedly by exploiting partial truncations of the polymerases N-terminal accessory domains.

biochemistry↗

Single cell RNA Sequencing Identifies G-protein Coupled Receptor 87 as a Novel Basal Cell Marker of Distal Honeycomb Cysts in Idiopathic Pulmonary Fibrosis

Idiopathic Pulmonary Fibrosis (IPF) is a progressive and fatal lung disease with limited therapeutic options. Epithelial reprogramming and honeycomb cysts are key pathological features of IPF, however, the IPF distal bronchiole cell subtypes and their potential contribution to IPF development and progression still remain poorly characterized. Here, we utilized single-cell RNA sequencing on enriched EpCAM+ cells of the distal IPF and Donor lung. Using the 10x Genomics platform, we generated a dataset of 47,881 cells and found distinct cell clusters, including rare cell types, such as suprabasal cells recently reported in the healthy lung. We identified G-protein coupled receptor (GPR) 87 as a novel surface marker of distal Keratin (KRT)5+ basal cells. GPR87 expression was localized to distal bronchioles and honeycomb cysts in IPF in situ by RNA Scope and immunolabeling. Modulation of GPR87 in primary human bronchial epithelial cells cultures resulted in impaired airway differentiation and ciliogenesis. Thus, GPR87 is a novel marker and potentially druggable target of KRT5+ basal progenitor cells likely contributing to bronchiole remodeling and honeycomb cyst development in IPF.

cell biology↗