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Biology subjects

Carmel, L.

Publications and source records attributed to Carmel, L..

7 recordsLinked to original sources

Internet-delivered cognitive behavioral therapy is associated with distinct blood small RNA profiles in panic disorder

Panic disorder associates with altered fear circuitry, autonomic dysregulation and stress-related immune perturbations, yet its molecular and treatment-response signatures remain poorly defined. Internet-delivered cognitive behavioral therapy (iCBT) is an effective first-line treatment with unexplained outcome variations across individuals. Here, we report altered profiles of small non-coding RNAs in peripheral blood mononuclear cells from panic disorder patients before and after iCBT, compared with longitudinally sampled healthy controls. Thirteen top-ranking microRNAs discriminated patients from controls and separated pre- and post-treatment states, both of which differed from controls. Correspondingly, baseline hsa-miR-125b-5p levels were significantly associated with post-iCBT symptom improvement. Transfer RNA-derived fragments (tRFs) showed even greater discriminatory power, with nuclear-Val-3'-tRF family members exhibiting a pronounced post-treatment shift. Pathway analyses of panic disorder-associated and CBT-responsive small RNA targets converged on immune-related pathways, supporting a role in inflammatory mechanisms and highlighting blood small non-coding RNAs as promising biomarkers of panic disorder and its therapeutic response.

molecular biology↗

RoAM: computational reconstruction of ancient methylomes and identification of differentially methylated regions

Identifying evolutionary changes in DNA methylation bears a huge potential for unraveling adaptations that have occurred in modern humans. Over the past decade, computational methods to reconstruct DNA methylation patterns from ancient DNA sequences have been developed, allowing for the exploration of DNA methylation changes during the past hundreds of thousands of years of human evolution. Here, we introduce a new version of RoAM (Reconstruction of Ancient Methylation), a flexible tool that allows for the reconstruction of ancient methylomes, as well as the identification of differentially methylated regions between ancient populations. RoAM incorporates a series of filtering and quality control steps, resulting in highly reliable DNA methylation maps that exhibit similar characteristics to modern maps. To showcase RoAMs capabilities, we used it to compare ancient methylation patterns between pre- and post-Neolithic revolution samples from the Balkans. Differentially methylated regions separating these populations are shown to be associated with genes related to regulation of sugar metabolism. Notably, we provide evidence for overexpression of the gene PTPRN2 in post-Neolithic revolution samples. PTPRN2 is a key regulator of insulin secretion, and our finding is compatible with hypoinsulinism in pre-Neolithic revolution hunter-gatherers. Additionally, we observe methylation changes in the genes EIF2AK4 and SLC2A5, which provide further evidence to metabolic adaptations to a changing diet during the Neolithic transition. RoAM offers powerful algorithms that position it as a key asset for researchers seeking to identify evolutionary regulatory changes through the lens of paleoepigenetics.

evolutionary biology↗

Newborn reactions to maternal prenatal stress alter umbilical cord blood tRNA fragments targeting cholinergic transcripts

Maternal perceived prenatal stress (PPS) is a known risk factor for diverse developmental impairments in newborns, but the underlying molecular processes are incompletely understood. Here, we report that maternal PPS altered the birth profiles of blood transfer RNA fragments (tRFs), 16-50nt long non-random cleavage products of tRNAs, in a sex-dependent manner. Importantly, comparing stressed versus control maternal and umbilical cord blood serum presented alterations that were not limited to individual tRFs, but rather reflected selective changes in particular tRF families grouped by their mitochondrial or nuclear genome origin, parental tRNA coded amino acid, and cleavage type. tRF families that show stress- and sex-specific effects, revealed shared length and expression patterns which were strongest in the female newborns. Several of these tRFs carry complementary motifs to specific cholinergic mRNAs, suggesting possible translational regulation similar to microRNAs. Compatible with the cholinergic regulation of stress reactions, those "CholinotRFs" achieved an AUC of 95% when classifying female newborns according to maternal PPS. Moreover, we found altered catalytic activity of serum acetylcholinesterase, which was particularly elevated in male newborns, marking a second sex-specific effect. Our findings demonstrate an association of tRF families patterns with newborns sex-specific stress response to PPS and may lead to better diagnosis and therapeutic tools for these and other stressors.

molecular biology↗

Candidate Denisovan fossils identified through gene regulatory phenotyping

Denisovans are an extinct group of humans whose morphology is mostly unknown. The scarcity of verified Denisovan fossils makes it challenging to study their anatomy, and how well they were adapted to their environment. We previously developed a genetic phenotyping approach to gain insight into Denisovan anatomy by detecting gene regulatory changes that likely altered Denisovan skeletal morphology. Here, we scan Middle Pleistocene crania for unclassified or disputed specimens that match predicted Denisovan morphology and thus might be related to Denisovans. We found that Harbin, Dali, and Kabwe 1 show a particularly good alignment with the Denisovan profile, with most of their phenotypes matching predicted Denisovan anatomy. We conclude that our genetic phenotyping approach could help classify unidentified specimens, and that Harbin, Dali, and Kabwe 1 exhibit a Denisovan-like morphology and could be closely linked to the Denisovan lineage.

genetics↗

Improved detection of methylation in ancient DNA

Reconstructing premortem DNA methylation levels in ancient DNA (aDNA) has led to breakthrough studies such as the prediction of anatomical features of the Denisovan, as well as the castration status of ancient horses. These studies relied on computationally inferring methylation levels from damage signals in naturally deaminated cytosines. Because of statistical constraints, this inference requires high-coverage sequencing, and is thus not only expensive but also restricted to samples with exceptional DNA preservation. Instead, a method to directly measure methylation levels in aDNA, as exists in modern DNA samples, would open the door to a more thorough and cost effective ability to study ancient DNA methylation. We have tested two methods for direct methylation measurement developed for modern DNA based on either bisulfite or enzymatic methylation treatments. We find that both methods preserve sufficient DNA yields to allow for methylation measurement. Bisulfite treatment, combined with a single stranded library preparation, shows the least reduction in DNA yields compared to no methylation treatment, as well as the least biases during methylation conversion. In addition, we show that applying bisulfite treatment to [~]0.4-fold coverage sample provides a methylation signal that is comparable to, or even better, than the computationally inferred one. We thus present a method to directly measure methylation in ancient DNA that is cost effective and can be used on a wide variety of ancient samples.

genomics↗

Gene ORGANizer: Linking Genes to the Organs They Affect

One of the biggest challenges in studying how genes work is understanding their effect on the physiology and anatomy of the body. Existing tools try to address this using indirect features, such as expression levels and biochemical pathways. Here, we present Gene ORGANizer (geneorganizer.huji.ac.il), a phenotype-based tool that directly links human genes to the body parts they affect. It is built upon an exhaustive curated database that links more than 7,000 genes to [~]150 anatomical parts using >150,000 gene-organ associations. The tool offers user-friendly platforms to analyze the anatomical effects of individual genes, and identify trends within groups of genes. We demonstrate how Gene ORGANizer can be used to make new discoveries, showing that chromosome X is enriched with genes affecting facial features, that positive selection targets genes with more constrained phenotypic effects, and more. We expect Gene ORGANizer to be useful in a variety of evolutionary, medical and molecular studies aimed at understanding the phenotypic effects of genes.

bioinformatics↗

Recent Regulatory Changes Shaped the Human Facial and Vocal Anatomy

SummaryRegulatory changes are broadly accepted as key drivers of phenotypic divergence. However, identifying regulatory changes that underlie human-specific traits has proven very challenging. Here, we use 63 DNA methylation maps of ancient and present-day humans, as well as of six chimpanzees, to detect differentially methylated regions that emerged in modern humans after the split from Neanderthals and Denisovans. We show that genes affecting the face and vocal tract went through particularly extensive methylation changes. Specifically, we identify widespread hypermethylation in a network of face- and voice-affecting genes (SOX9, ACAN, COL2A1, NFIX and XYLT1). We propose that these repression patterns appeared after the split from Neanderthals and Denisovans, and that they might have played a key role in shaping the modern human face and vocal tract.View Full Text

evolutionary biology↗