@article{belikoff_davis_williamson_britt_scott_2024, title={Identification of a gene promoter active in<i> Lucilia</i><i> sericata</i> larval salivary glands using a rapid transient expression assay}, volume={173}, ISSN={["1879-0240"]}, url={https://doi.org/10.1016/j.ibmb.2024.104163}, DOI={10.1016/j.ibmb.2024.104163}, abstractNote={Tissue-specific gene promoters are desired as they provide the specificity needed for control of gene expression in transgenic animals. Here we describe a relatively rapid two-component transient expression assay that was used to identify a gene promoter active in the larval salivary glands of the green blow fly, Lucilia sericata. Sterile L. sericata maggots are widely used for wound debridement. A larval salivary gland gene promoter could be used to make maggots that secrete factors for enhanced wound therapy. Embryos from a line that carry a tetracycline transactivator (tTA)-activated red fluorescent protein gene were injected with plasmid DNA with the tTA gene driven by a constitutive or tissue-specific gene promoter. The hatched larvae were reared on diet and then examined for red fluorescence. A promoter from the LsCG30371 gene was active in the larval salivary glands. The tissue-specificity of the promoter was subsequently confirmed with stable transgenic lines that carried the LsCG30371-tTA gene. The relatively rapid transient expression assay could potentially be used to determine the tissue-specificity of other gene promoters. Further, the stable LsCG30371-tTA lines could be used to make sterile maggots that secrete factors from the salivary glands for enhanced wound healing.}, journal={INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY}, author={Belikoff, Esther J. and Davis, Rebecca J. and Williamson, Megan E. and Britt, John W. and Scott, Maxwell J.}, year={2024}, month={Oct} }
 @article{karakis_jabeen_britt_cordiner_mischler_li_miguel_rao_2023, title={Laminin switches terminal differentiation fate of human trophoblast stem cells under chemically defined culture conditions}, volume={299}, ISSN={["1083-351X"]}, DOI={10.1016/j.jbc.2023.104650}, abstractNote={Human trophoblast stem cells (hTSCs) have emerged as a powerful tool to model early placental development <i>in vitro</i>. Analogous to the epithelial cytotrophoblast in the placenta, hTSCs can differentiate into cells of the extravillous trophoblast (EVT) lineage or the multinucleate syncytiotrophoblast (STB). Here we present a chemically defined culture system for STB and EVT differentiation of hTSCs. Notably, in contrast to current approaches, we neither utilize forskolin for STB formation nor transforming growth factor-beta (TGFβ) inhibitors or a passage step for EVT differentiation. Strikingly, the presence of a single additional extracellular cue–laminin-111–switched the terminal differentiation of hTSCs from STB to the EVT lineage under these conditions. In the absence of laminin-111, STB formation occurred, with cell fusion comparable to that obtained with differentiation mediated by forskolin; however, in the presence of laminin-111, hTSCs differentiated to the EVT lineage. Protein expression of nuclear hypoxia-inducible factors (HIF1α and HIF2α) was upregulated during EVT differentiation mediated by laminin-111 exposure. A heterogeneous mixture of Notch1<sup>+</sup> EVTs in colonies and HLA-G<sup>+</sup> single-cell EVTs were obtained without a passage step, reminiscent of heterogeneity <i>in vivo</i>. Further analysis showed that inhibition of TGFβ signaling affected both STB and EVT differentiation mediated by laminin-111 exposure. TGFβ inhibition during EVT differentiation resulted in decreased HLA-G expression and increased Notch1 expression. On the other hand, TGFβ inhibition prevented STB formation. The chemically defined culture system for hTSC differentiation established herein facilitates quantitative analysis of heterogeneity that arises during hTSC differentiation and will enable mechanistic studies <i>in vitro</i>.}, number={5}, journal={JOURNAL OF BIOLOGICAL CHEMISTRY}, author={Karakis, Victoria and Jabeen, Mahe and Britt, John W. and Cordiner, Abigail and Mischler, Adam and Li, Feng and Miguel, Adriana San and Rao, Balaji M.}, year={2023}, month={May} }