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Andriollo, A.

Publications and source records attributed to Andriollo, A..

2 recordsLinked to original sources

The One Click Wonder: a retrained automated segmentation pipeline that enables quantitative and modular analysis of C. elegans embryos

High-throughput approaches have transformed the study of gene regulation by enabling quantitative, genome-scale analyses in both genomics and imaging. However, applying these methods to intact organisms remains challenging, particularly for high-throughput, 3D imaging. In Caenorhabditis elegans, generalist segmentation models often perform poorly due to rapid changes in nuclear size, shape, and density. To overcome this obstacle, we developed One Click Wonder (OCW), an automated pipeline that pairs a retrained Cellpose model with stage-specific parameter selection to deliver accurate, high-throughput segmentation of embryos. We further introduce the Biological Annotation and Association Mapper (BAAM), which integrates segmentation with spot detection, to enable single-cell quantitation. Applied to the pioneer factor pha-4/FoxA, this pipeline revealed distinct cell populations with an eight-fold range in transcriptional burst frequency. These findings demonstrate that OCW and BAAM provide a modular, scalable pipeline for quantitative, single-cell analysis of gene expression in C. elegans embryos.

bioinformatics↗

ChAHP2 and ChAHP control diverse retrotransposons by complementary activities

Retrotransposon control in mammals is an intricate process that is effectuated by a broad network of chromatin regulatory pathways. We previously discovered ChAHP, a protein complex with repressive activity against SINE retrotransposons, composed of the transcription factor ADNP, chromatin remodeler CHD4, and HP1 proteins. Here we identify ChAHP2, a protein complex homologous to ChAHP, wherein ADNP is replaced by ADNP2. ChAHP2 is predominantly targeted to ERVs and LINEs, via HP1{beta}-mediated binding of H3K9 trimethylated histones. We further demonstrate that ChAHP also binds these elements in a mechanistically equivalent manner to ChAHP2, and distinct from DNA sequence-specific recruitment at SINEs. Genetic ablation of ADNP2 alleviates ERV and LINE1 repression, which is synthetically exacerbated by additional depletion of ADNP. Together, our results reveal that the ChAHP and ChAHP2 complexes function to control both non-autonomous and autonomous retrotransposons by complementary activities, further adding to the complexity of mammalian transposon control.

molecular biology↗