Biology subjects

Bahrudeen, M.

Publications and source records attributed to Bahrudeen, M..

3 recordsLinked to original sources

bioRxiv2026

Profiling of HeLa nucleoplasmic and nucleolar RNAs by Halo-seq proximity labeling

Subcellular RNA localization is a key regulator of gene expression, but transcriptome wide characterization of RNAs enriched in specific cellular compartments has been hindered by methodological limitations in throughput and spatial resolution. Halo-seq is an RNA proximity-labeling approach that enables the extraction of RNAs located near virtually any Halo-tagged bait protein. However, its broader application has been restricted by the limited availability of the required Halo ligand. Here we present a Halo-seq dataset profiling the nucleoplasmic and nucleolar transcriptomes of HeLa cells. Through experimental and computational validation, we demonstrate that our optimized Halo-seq protocol achieves high spatial specificity, enabling robust mapping of compartment-enriched RNA populations.

molecular biology↗

bioRxiv2026

dirCLIP profiles variant-specific RNA-protein interactions via nanopore long-read sequencing

RNA binding proteins (RBPs) control gene expression through their activities in essentially all processing steps of coding and noncoding RNAs and are dysregulated in disease. With >95% of human multi-exon genes undergoing alternative splicing, the inability to assign RBP sites to distinct RNA variants fundamentally limits our understanding of RNA regulation. We present dirCLIP, a method combining UV crosslinking and immunoprecipitation (CLIP) with amplification-free direct nanopore long-read sequencing preserving full-length transcripts. dirCLIP employs two complementary strategies: direct RNA sequencing detecting amino acid adduct-induced perturbations in current signals and direct cDNA sequencing capturing binding sites as mutations. Benchmarking dirCLIP with SRSF3 demonstrated >75% concordance with short-read-based data, revealed isoform-selective RNA binding and enabled detection of co-occurring binding sites in single RNA molecules. Application to the noncanonical RBP HMGA1 uncovered new AT-hook mediated RNA variant-specific interactions. dirCLIP fundamentally transforms our ability to interrogate RNA regulation of distinct isoforms and transcript variants with direct implications to disease mechanisms and development of RNA therapeutics.

molecular biology↗

bioRxiv2021

Positive supercoiling buildup is a trigger of E. coli's short-term response to cold shock

Adaptation to cold shock (CS) is a key survival skill of gut bacteria of warm-blooded animals. In E. coli, this skill emerges from a complex transcriptional program of multiple, timely-ordered shifts in gene expression. We identified short-term, cold shock repressed (CSR) genes by RNA-seq and provide evidence that their variability in evolutionary fitness is low and that their responsiveness to cold emanates from intrinsic features. Given that their single-cell variability in protein numbers increases after CS, we hypothesized that the responsiveness of a large portion of CSR genes is triggered by the high propensity for transcription locking due to positive supercoiling buildup (PSB). We then proposed a model of this phenomenon and, in support, show that nearly half of CSR genes are highly responsive to Gyrase inhibition. Also, their response strengths to CS and Gyrase inhibition correlate and most CSR genes increase their single-cell variability in protein numbers. Further, during CS, the cells nucleoid density increases (in agreement with increased numbers of positive supercoils), their energy levels become depleted (while the resolving of positive supercoils is ATP dependent), and the colocalization of Gyrases and the nucleoid increases (in agreement with increased time length for resolving supercoils). We conclude that high sensitivity to PSB is at the core of the short-term, cold shock responsive transcriptional program of E. coli and propose that this gene feature may be useful for providing temperature sensitivity to chromosome-integrated synthetic circuits.

systems biology↗