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Charles, M. A.

Publications and source records attributed to Charles, M. A..

2 recordsLinked to original sources

Whole genome assembly and annotation of the acorn weevil, Curculio nanulus (Coleoptera: Curculionidae)

The acorn weevil Curculio nanulus (Coleoptera: Curculionidae) is a seed predator that lays its eggs inside developing acorns and hickory nuts in the western United States. The female weevil uses her elongated rostrum to excavate a hole into the seed, creating a protected site for oviposition. Natural history traits among Curculio species--such as host-specificity and variation in larval diapause--suggest a dynamic evolutionary relationship with their host plants. These traits are best studied through a comparative genomic framework, but such analyses cannot currently be undertaken due to the lack of whole genome assemblies for Curculio species. To address this gap, we generated a whole genome assembly for C. nanulus using PacBio HiFi sequencing. The resulting assembly is [~]1.5 Gbp in length, with high contiguity (contig N50 = 7.7 Mbp) and gene completeness (USCO score: 97.46%). To enable comparative analysis, we also assembled the genome of the pecan weevil, Curculio caryae, using publicly available PacBio HiFi reads. For both species, we annotated repetitive elements and protein-coding genes, and compared these features with those of other weevil genomes. Our results reveal a marked expansion of repetitive elements within Curculio and its close relatives. These genomic resources provide a foundation for investigating seed predation, co-speciation, and host-parasite evolutionary dynamics in Curculio and related taxa, as well as their impacts on forest ecology.

genomics↗

Placental DNA methylation signatures of maternal smoking during pregnancy and potential impacts on fetal growth

Maternal smoking during pregnancy (MSDP) contributes to poor birth outcomes, in part through disrupted placental functions, which may be reflected in the placental epigenome. We meta-analyzed the associations between MSDP and placental DNA methylation (DNAm) and between DNAm and birth outcomes within the Pregnancy And Childhood Epigenetics (PACE) consortium (7 studies, N=1700, 344 with any MSDP). We identified 1224 CpGs that were associated with MSDP, of which 341 associated with birth outcomes and 141 associated with gene expression. Only 6 of these CpGs were consistent with the findings from a prior meta-analysis of cord blood DNAm, demonstrating substantial tissue-specific responses to MSDP. The placental MSDP associated CpGs were enriched for growth-factor signaling, hormone activity, inflammation, and vascularization, which play important roles in placental function. We demonstrate links between placental DNAm, MSDP and poor birth outcomes, which may better inform the mechanisms through which MSDP impacts placental function and fetal growth.

genomics↗