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Biology subjects

Huffman, C.

Publications and source records attributed to Huffman, C..

4 recordsLinked to original sources

Across Species Identification of Genes Bridging Cognition and Reproduction

Evolutionary success in mammals requires coordinated regulation of cognitive functions and reproductive capacity. Such coordination must involve shared genes and molecular pathways between the brain and germ cells, yet direct evidence linking cognition to reproduction across species remains limited. Here, proteomic and transcriptomic analyses were performed experimentally in Ovis aries and Rattus norvegicus, while transcriptomic datasets from Mus musculus, Macaca mulatta, and Homo sapiens were analyzed in silico. We identified 8,464 protein-coding genes shared between the brain and sperm/testis and conserved across five species. In rats, 8,444 of these genes were also shared between the brain and the ovary. Functional annotation classified 3,890 genes as associated with both neurological and reproductive functions, and 1,752 as uncharacterized in these contexts, highlighting candidates for future studies on reproductive and neurological disorders. These findings reveal a deeply conserved genetic network linking neurological and reproductive systems, underscoring the evolutionary interplay that supports mammalian fitness.

evolutionary biology↗

High-avidity TCR signaling induces a distinct KLR-positive exhaustion state in human tumor-infiltrating CD8 T cells associated with immunotherapy response

T cells adopt diverse states in human disease, with tumor-specific CD8 T cells serving as the quintessential example. These cells are critical for immunotherapy response, yet acquire hypofunctional states of exhaustion that impair treatment efficacy. While significant heterogeneity is observed among exhausted CD8 T cells (TEX), the mechanisms directing their unique phenotypes remain unresolved, limiting our efforts to augment TEX cell function. Here, we profile TEX cells in human head and neck squamous cell carcinoma (HNSCC) tumors and define a major mechanism regulating their cell state. With single-cell RNA and T cell receptor (TCR) sequencing of 106,667 tumor-infiltrating CD8 T cells, we define and validate three fundamental TEX subsets, each harboring dominant clonotypes: a progenitor subset (TPEX) and two intra-tumoral populations marked by intermediate (TEX-int) or high expression of inhibitory receptors, including killer cell lectin-like receptors, such as KLRC1/NKG2A (TEX-KLR). Using an in vitro model, we show that TCR avidity-dependent NFAT signaling governs an axis between the TEX-int and TEX-KLR states across human cancers, with high-avidity signaling driving the TEX-KLR state. Additionally, we uncover that interleukin-12 signaling selectively antagonizes high-avidity TEX-KLR-specific genes, despite broadly potentiating activation and cytotoxicity. Finally, we find that TEX-int and TEX-KLR cells are associated with anti-PD-1 response in HNSCC, with both of these cell types enriched near viable cancer cells following treatment. Together, these findings reveal that TCR avidity orchestrates tumor-infiltrating TEX cell states through NFAT signaling, a tunable axis that may be targeted to improve TEX cell function.

immunology↗

Functional insights into the photoactive yellow protein family from homologs, multidomain proteins and inferred pyp operons

Photoactive Yellow Protein (PYP) is a model system for functional protein dynamics and a prototype of the PAS domain superfamily. It is a bacterial photoreceptor that triggers a range of responses in different bacteria: phototaxis, biosynthesis of photo-protective pigments, and light regulation of biofilm formation. An important gap in knowledge on PYP is the signal transduction chain that guides the initial signal from the photoreceptor to various biological responses. Here we report an expanded set of 984 PYP homologs, providing information on sequence conservation and variation. We analyze this set of PYPs using two bioinformatics approaches to identify candidate proteins that are functionally related to PYP. First, we identified 153 multi-domain proteins containing PYP and analyzed the domain composition of these proteins. Specific preferences for N- or C-terminal placement of the PYP domain were observed. Second, we identified 113 predicted multi-gene operons containing the pyp gene. These two approaches yielded multiple candidates for proteins in the signal transduction chain associated with PYP, particularly histidine kinase (implying phosphorylation), methyl accepting chemotaxis protein (implying phototaxis), and GGDEF and EAL proteins (implying a role of c-di-GMP and biofilm formation). Some of these candidates were present only in multi-domain proteins and others only in pyp operons. Overexpression of the PYP domain from the MCP-fusion protein from Nitrincola alkalilacustris yielded a protein with an absorbance maximum of 447 nm and an overall photocycle rate of 0.5 seconds. Our results provide a clear basis for future experimental work on identifying signal transduction partners of PYP.

microbiology↗

Zika viruses of both African and Asian lineages cause fetal harm in a vertical transmission model

Congenital Zika virus (ZIKV) infection was first linked to birth defects during the American outbreak 1-3. It has been proposed that mutations unique to the Asian/American-genotype explain, at least in part, the ability of Asian/American ZIKV to cause congenital Zika syndrome (CZS) 4,5. Recent studies identified mutations in ZIKV infecting humans that arose coincident with the outbreak in French Polynesia and were stably maintained during subsequent spread to the Americas 5. Here we show that African ZIKV can infect and harm fetuses and that the S139N mutation that has been associated with the American outbreak is not essential for fetal harm. Our findings, in a vertical transmission mouse model, suggest that ZIKV will remain a threat to pregnant women for the foreseeable future, including in Africa, southeast Asia, and the Americas. Additional research is needed to better understand the risks associated with ZIKV infection during pregnancy, both in areas where the virus is newly endemic and where it has been circulating for decades.

microbiology↗