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Corona-Gomez, J. A.

Publications and source records attributed to Corona-Gomez, J. A..

4 recordsLinked to original sources

SiteCELL enables on-site PBMCs purification and cryopreservation for immune single cell profiling of diverse ancestries

Single cell genomics has improved our knowledge of immune function and heterogeneity. In recent years, the steady increase in the number of cells and individuals profiled as part of large multinational projects has enabled the characterization of cellular differences across human populations and ancestries. However, methods for collecting and processing peripheral blood mononuclear cells (PBMCs) for downstream single cell sequencing are difficult to implement in remote and rural settings. This has resulted in a lack of representation of underserved communities across the Global South in current initiatives. Hence, we developed SiteCELL, a method that enables purification and cryopreservation of PBMCs from whole blood at the site of collection using minimal laboratory equipment and without electricity. By comparing matched samples of purified PBMCs, we showed that SiteCELL performs as well as ficoll density gradient (FDG), both in laboratory and rural settings. This method ensures accurate recovery of cell type proportions and excels in reducing stress and minimizing variability across sampling batches. These advantages make it particularly well suited for implementation in challenging settings across countries, thereby enabling the inclusion of underrepresented ancestries in cellular atlases.

immunology↗

Evolutionary conservation of secondary structures in the lncRNAs of plants

LncRNAs are essential regulators of eukaryotic gene expression. They exert their gene regulatory functions by interacting with DNA, RNA, and protein. These functions are considered at least in part associated with their capacity to fold into complex three-dimensional structures. The conservation of lncRNA structure in mammalian genomes has been assessed in several studies, however, very little is known about the conservation of lncRNA structures in plants. Here, we analyze the structural conservation of lncRNAs in Brassicaceae, using a whole genome alignment of 16 Brassicaceae species. We found that 44.2% (1925 of 4354) of the intergenic lncRNAs (lincRNAs) and 75.1% (1549 of 2060) of the natural antisense transcripts (NATs) of Arabidopsis thaliana have conserved structural motifs in at least 2 of the 16 species. Also, 3612 lncRNAs have conserved structural motifs in multiple species; 2264 of which are tissue-specific, and 841 can be associated with a function by a co-expression network in A. thaliana. Indeed, we find evidence for the conservation of structural motifs in several lncRNAs with known functions, including, lncCOBRA1, FLORE, IPS1, ELENA1 and COOLAIR. The latter was shown previously to have a conserved structure. Overall, we have identified numerous lncRNAs with conserved structures in Brassicaceae that warrant further experimental exploration in vivo to understand whether these lncRNAs and their conserved structures are of biological significance.

bioinformatics↗

Transcriptome-guided annotation and functional classification of long non-coding RNAs in Arabidopsis thaliana

Long non-coding RNAs (lncRNAs) are a prominent class of eukaryotic regulatory genes. Despite the numerous available transcriptomic datasets, the annotation of plant lncRNAs remains based on dated annotations that have been historically carried over. We present a substantially improved annotation of Arabidopsis thaliana lncRNAs, generated by integrating 224 transcriptomes in multiple tissues, conditions, and developmental stages. We annotate 6764 lncRNA genes, including 3772 that are novel. We characterize their tissue expression patterns and find 1425 lncRNAs are co-expressed with coding genes, with enriched functional categories such as chloroplast organization, photosynthesis, RNA regulation, transcription, and root development. This improved transcription-guided annotation constitutes a valuable resource for studying lncRNAs and the biological processes they may regulate.

genomics↗

Splicing conservation signals in plant long non-coding RNAs

Long non-coding RNAs (lncRNAs) have recently emerged as prominent regulators of gene expression in eukaryotes. LncRNAs often drive the modification and maintenance of gene activation or gene silencing states via chromatin conformation rearrangements. In plants, lncRNAs have been shown to participate in gene regulation, and are essential to processes such as vernalization and photomorphogenesis. Despite their prominent functions only over a dozen lncRNAs have been experimentally and functionally characterized. Similar to its animal counterparts, the rates of sequence divergence are much higher in plant lncRNAs than in protein coding mRNAs, making it difficult to identify lncRNA conservation using traditional sequence comparison methods. Beyond this, little is known about the evolutionary patterns of lncRNAs in plants. Here, we characterized the splicing conservation of lncRNAs in Brassicaceae. We generated a whole-genome alignment of 16 Brassica species and used it to identify synthenic lncRNA orthologues. Using a scoring system trained on transcriptomes from A. thaliana and B. oleracea, we identified splice sites across the whole alignment and measured their conservation. Our analysis revealed that 17.9% (112/627) of all intergenic lncRNAs display splicing conservation in at least one exon, an estimate that is substantially higher to previous estimates of lncRNA conservation in this group. Our findings agree with similar studies in vertebrates, demonstrating that splicing conservation can be evidence of stabilizing selection. We provide conclusive evidence for the existence of evolutionary deeply conserved lncRNAs in plants and describe a generally applicable computational workflow to identify functional lncRNAs in plants.

genomics↗